Engine Running outa ideas

I hate people that 'think' they can slap on this or leave that off and then when it doesn't go right they sell it off for someone else to deal with.
Now that you're 'the one' we need you to verify some things so we can help you get this 'mid life mess' running right.
Verify what computer is in the car, and if the car is actually an original V8 GT car. We can go from there.
I love those guys....generally can buy those cars for pennies on the dollar if they don't start parting them out...... Hell my current beater is a 93 4cyl dressed as a 93 gt, It was a cluster, now no one would have a clue unless they checked the vin or I pointed it out.. if the 8th didgit isn't E you might have a headache on your hands
 
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I love those guys....generally can buy those cars for pennies on the dollar if they don't start parting them out...... Hell my current beater is a 93 4cyl dressed as a 93 gt, It was a cluster, now no one would have a clue unless they checked the vin or I pointed it out.. if the 8th didgit isn't E you might have a headache on your hands
8th is E on this rig.
 
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Ok

So
Lookin for advice.

89 GT 5.0 Edelbrock intake (all I know Mod wise)

Bought Ford Code reader
Got a 23 TPS is all for now
Also 98 ON the KOEO test.

Car works ok
Pulls hard
Needs a set of rear clutches (1 wheel spin)
Idle surges a bit.
Fuel pump goes 2-3 Seconds then off at KO
Any away

My main issues is that she won’t start sometimes after running for 30 mins.

Cranks OK
won’t fire up.

If I disconnect Bat for 5 mins (something clears)
Car fires right up.

I have not done the idle Surge/start checklist yet as I dont think I’ll find anything obvious.

Looked for vacuum leaks
Changed CTS/Coolant sender and TFI so far

Likely put a new TPS on as well..

Car has Cold intake
MAF removed (heard that’s OK with the intake that’s on it now..

Thanks for reading folks

Just looking for new places to look..
When you swapped out the intake did you reconnect the ground wire and when you did the swap you put the corresponding bottom ?

Maybe instead of going by the words of the grapevine you should go to the source...Theres lots of TECHNICAL INFO TO KNOW BEFORE INSTALLATION...


On my Edelbrock intake #3881 theres a snowballs chance in hell that both would mate up perfectly as the stock intake has oval ports and the Edelbrock intake has rectangular ports...

Its been years but from what I remember my buddy had a EFI performer intake too and when he installed it he had problems but found out he failed to install a baffle plate and didnt install the egr plate either....Both parts mentioned plus all emissions hookups were definately needed to be hooked-up after calling Edelbrock fuming and finding out the old owner of the intake was the problem because he bought it used off craigslist and actually should of bought a new one because the missing parts costed him a pretty penny and 5 weeks time to get them........LOL

When the intake was swapped out there were a number of things that got disconnected..Id go back and inspect every plug that was pulled because sometimes those connectors dont go back on all the way but feel like they hit home....The MAP BAP TPS also TFI module and AIT sensor plugs are famous for this...

Like others have said you need the MassAirflow sensor ...Its the primary form of measurement and the TPS becomes a slave to it...You kinda need the BAP too unless you put a resistor or have a chip w/tuner program......

Once you disconnect the MAF the ECU is supposed to go into Limp Mode if the BAP and TPS sensors are good.........

Screenshot 2022-10-29 121555.jpg


With the EEC-IV system when my MAF totally fails I dont get a code...I only get a code for the MAF if the power or signals arent processing correctly with-in the ECU which is weird but from memory I think it has its own internal chip too making it kind of a standalone sensor even though its wired in and sensed by the ECU the ECU goes by the MAF's parameters that are programmed in so if you use a different size MAF youre gonna have to get a chip and do a MAF transfer profile enhancement or find someone who can erase your bin file and burn a new one with proper changes........

Another thing to note is I recently was informed that Moates is discontinuing their chips, chip repairs also technical support and going into retirement so the only alternative is the non-EEC-IV based but in a EEC-IV case ;- The Pimp Megasquirt system..........

Screenshot 2022-10-29 122029.jpg


The way I know when my MAF isnt working is by hooking up my laptop to it and use my Moates dashboard to read the voltage or hooking it up to my Matco OB2 reader and right now I bet youre saying that the EEC-IV is OBD1 and it is- but with one of these adapters below I can use the PID from the Matco handheld and a download from the internet to read vehicle vitals as its running and even not running plus I also go right to the MAF when my vehicle starts up and instantly shuts off like the battery in my QH chip died or starts up and instantly bogs down and shuts when the throttle is cracked like I lost fuel pressure........

IMG_20221019_165002.jpg

IMG_20221019_165114.jpg



A friend of mine bought an 89 and the old owner changed the longblock out and when removing the engine he mustve snagged the MAF plug on the block when yanking the engine out because the wires under the loom were stretched so badly there was literally 3 strands on 2 wires making the flow of juice not happen right and wasnt too good but with a multimeter the problem was found because those wires showed high resistance plus they intermingled when I did a cross-wire test on the other wires on the MAF plug....

Alls you have to do is disconnect the ECU plug from the ECU and use this schematic starting at pin #1 go down the line pin by pin with one probe and hook the other probe to its corresponding termination to see if you get an audible beep and then touch the other pins to make sure theyre not melted or rubbed raw somewhere in the harnesss causing a short to the same wire.....

88-91_5.0_EEC_Wiring_Diagram1.gif


Another problem area are the Salt and Pepper shakers......10-12 years ago on another buddies car his connectors were a lil toasty due to a brake fluid fire and he needed to repin every wire in both connectors both male and female sides but opted to use solder and shrink tubing to hardwire the ECU harness to the Injector harness.......

It took a lil bit using a cheap Radioshack 40watt soldering iron outside in 50 degree weather but the car actually ran way better than before the fire too.....

Good Luck
 
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When you swapped out the intake did you reconnect the ground wire and when you did the swap you put the corresponding bottom ?

Maybe instead of going by the words of the grapevine you should go to the source...Theres lots of TECHNICAL INFO TO KNOW BEFORE INSTALLATION...


On my Edelbrock intake #3881 theres a snowballs chance in hell that both would mate up perfectly as the stock intake has oval ports and the Edelbrock intake has rectangular ports...

Its been years but from what I remember my buddy had a EFI performer intake too and when he installed it he had problems but found out he failed to install a baffle plate and didnt install the egr plate either....Both parts mentioned plus all emissions hookups were definately needed to be hooked-up after calling Edelbrock fuming and finding out the old owner of the intake was the problem because he bought it used off craigslist and actually should of bought a new one because the missing parts costed him a pretty penny and 5 weeks time to get them........LOL

When the intake was swapped out there were a number of things that got disconnected..Id go back and inspect every plug that was pulled because sometimes those connectors dont go back on all the way but feel like they hit home....The MAP BAP TPS also TFI module and AIT sensor plugs are famous for this...

Like others have said you need the MassAirflow sensor ...Its the primary form of measurement and the TPS becomes a slave to it...You kinda need the BAP too unless you put a resistor or have a chip w/tuner program......

Once you disconnect the MAF the ECU is supposed to go into Limp Mode if the BAP and TPS sensors are good.........

Screenshot 2022-10-29 121555.jpg


With the EEC-IV system when my MAF totally fails I dont get a code...I only get a code for the MAF if the power or signals arent processing correctly with-in the ECU which is weird but from memory I think it has its own internal chip too making it kind of a standalone sensor even though its wired in and sensed by the ECU the ECU goes by the MAF's parameters that are programmed in so if you use a different size MAF youre gonna have to get a chip and do a MAF transfer profile enhancement or find someone who can erase your bin file and burn a new one with proper changes........

Another thing to note is I recently was informed that Moates is discontinuing their chips, chip repairs also technical support and going into retirement so the only alternative is the non-EEC-IV based but in a EEC-IV case ;- The Pimp Megasquirt system..........

Screenshot 2022-10-29 122029.jpg


The way I know when my MAF isnt working is by hooking up my laptop to it and use my Moates dashboard to read the voltage or hooking it up to my Matco OB2 reader and right now I bet youre saying that the EEC-IV is OBD1 and it is- but with one of these adapters below I can use the PID from the Matco handheld and a download from the internet to read vehicle vitals as its running and even not running plus I also go right to the MAF when my vehicle starts up and instantly shuts off like the battery in my QH chip died or starts up and instantly bogs down and shuts when the throttle is cracked like I lost fuel pressure........

IMG_20221019_165002.jpg

IMG_20221019_165114.jpg



A friend of mine bought an 89 and the old owner changed the longblock out and when removing the engine he mustve snagged the MAF plug on the block when yanking the engine out because the wires under the loom were stretched so badly there was literally 3 strands on 2 wires making the flow of juice not happen right and wasnt too good but with a multimeter the problem was found because those wires showed high resistance plus they intermingled when I did a cross-wire test on the other wires on the MAF plug....

Alls you have to do is disconnect the ECU plug from the ECU and use this schematic starting at pin #1 go down the line pin by pin with one probe and hook the other probe to its corresponding termination to see if you get an audible beep and then touch the other pins to make sure theyre not melted or rubbed raw somewhere in the harnesss causing a short to the same wire.....

88-91_5.0_EEC_Wiring_Diagram1.gif


Another problem area are the Salt and Pepper shakers......10-12 years ago on another buddies car his connectors were a lil toasty due to a brake fluid fire and he needed to repin every wire in both connectors both male and female sides but opted to use solder and shrink tubing to hardwire the ECU harness to the Injector harness.......

It took a lil bit using a cheap Radioshack 40watt soldering iron outside in 50 degree weather but the car actually ran way better than before the fire too.....

Good Luck
Awesome post,
Thanks for that

I just took some pics to post.

I never installed the manifold so I’d need to pull apart to verify the install was done correct.
Not a big deal.

It’s the Edelbrock upper/lower 3820.

I’ll also install the TPS AND run KOEO as soon as parts arrive

Anyway here’s pics

The EGR vacuum goes nowhere but there’s the VAC block available with nothing attached
 

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That's not going to be fun someone swapped a whole bunch of stuff into an 89 chassis. The two connectors not plugged in by the intake pipe where a maf would be look like the a/c cut out relay by the tower and the round one looks like its for the purge solenoid but I'm going of memory and haven't messed with an 87-88 SD wiring harness in years

I would start by repairing all the vaccum lines, and smoke testing it.
 
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The two connectors not plugged in by the intake pipe where a maf would be look like the a/c cut out relay by the tower and the round one looks like its for the purge solenoid but I'm going of memory and haven't messed with an 87-88 SD wiring harness in years


That’s correct. Ac WOT relay and evap purge harness. Not necessarily speed density specific as they were on the ‘89 harness as well. Ac is gone so that’s not needed but I see the charcoal canister so I would hook that back up.



But yeah, someone swapped an 87-88 speed density ECU on this ‘89. My question is if the MAF plug is present and just tucked, or if this entire harness is out of an 87 or 88.

You can look at the o2 sensor harness to determine. The engine side of the o2 harness will have 5 wires if it’s an ‘87 harness, or 8 wires if an 88 or later.

If you poke around the various harnesses a bit. You might see part number labels still on them. See if any start with E7 or E8 part numbers, rather than E9.

Is this the source of all the OPs problems? Unknown, but he should still understand what he’s working with here.
 
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Will an 87/88 ECU harness connect to the 89 dash harness correctly? I want to say 87-90 have the two plugs by the booster so should be okay physically connecting up but what about pinout?
 
Will an 87/88 ECU harness connect to the 89 dash harness correctly? I want to say 87-90 have the two plugs by the booster so should be okay physically connecting up but what about pinout?

1988 would probably work fine with an 89 dash harness as MAF was available that year in CA.

1987 might not work because there were some differences in how Ford routed the pin 30 that year vs 88+.

As a general rule, one should try and keep all harnesses from the same year. Ford did some slight changes here and there over the years and all it takes is one wire not being present to cause issues that cause people to throw in the towel on a project car and sell it to the next guy when they can’t figure out why it won’t run right
 
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1988 would probably work fine with an 89 dash harness as MAF was available that year in CA.

1987 might not work because there were some differences in how Ford routed the pin 30 that year vs 88+.

As a general rule, one should try and keep all harnesses from the same year. Ford did some slight changes here and there over the years and all it takes is one wire not being present to cause issues that cause people to throw in the towel on a project car and sell it to the next guy when they can’t figure out why it won’t run right
I’m gonna look for some numbers today on the harness.

Install the new TPS (reading high always)

See if that clears my 23 code
Then do the
Idle reset.

Hopefully that takes car of my No start hot

If not
Go to the Salt/pepper shakers and start probing for Volts/gnds during the no start conditions
 
Sorry for the long post, that being said, here we go. I agree with 90% of everything posted. With one expensive caveat, No need for aftermarket ECU unless you are gonna race it professionally..... Stock EEC will do most of what it will do with the right hardware. Get a Moates Quarterhorse with Binary Editor software. Under $350 at your door in under a week. While you have the cover off replace capacitors $15-ish for kit on Ebay or Amazon. Watch Matt with Leech Motorsports on You tube. Email him for help and direction. He got me started with tuning my car. It can feel overwhelming at first but he has a tutorial on YT that steps you all the way thru install hardware/software set up and basic tune set up. You have real time datalog, shift on the fly tuning and uses all the factory hardware and sensors. Best money I ever spent. No other single upgrade compares. All that at 1/3 cost. Buy some beer or soda sit back and get to tuning. If you get to a point where you need help they can do online real time thru your laptop while the car is running $85/hr or send them your data log and tune and they will make changes or recommendations most times for free. As far as SD vs MAF QH works on both. Just make sure the pin out on the harness is correct and for sure verify O2 harness as there are some differences between yrs and SD, MAF. As far as main harness, don't buy new one if it isn't chopped up as the red pin lock can be removed and wires moved. Pull directions for a MAF coversion and reverse the proceedure to go from MAF to SD. VAC LEAKS #1. base idle reset #2 as all the resets in the world means crap with vacuum leaks. QH can disable EGR and Emissions, so that will eliminate a lot of that headache. If you just have to have a Holley, well he has videos on that to. Even if you don't buy one, watch the video as he breaks down why we set things where do and the reason it matters based on Ford programming. FYI, Mega squirt is SD based so I wouldn't worry about MAF sensor too much. For the cost of the replacement sensor you could already be tuning the computer you have. #3 confirm all sensors and timing.No glory in replacing perfectly good parts b/c you didn't test or confirm. Start @ 10degs base as reset can be tricky if someone jacked the timing around. IAC gets a lot of blame for idle surge, but timing is a bigger issue. Idle Oscillosion timing overcorrection is in the program and the real culprit. If surge stops when you pull the spout out, that's why. If not then check IAC. #4 pull battery cables for at least 25 min to reset kamref, (keep alive memory) as the adaptive learning already has you over a barrel.... *DO THIS EVERY TIME YOU MAKE ANY CHANGES, so you are not fighting previously learned bad behavior. Don't worry about TPS voltage if it's between .75 and 1.25 vdc Ideally you want it in the .85-.95 range with a smooth even sweep thru to 5vdc. EEC resets the tps (ratch) base voltage at every key cycle anyways. If you adjust it while running, restart the car or could throw you a curve ball if it goes into part throttle map. #4 Valve springs! Stocks are POS. You will gain HP on top end with that one alone. Google and forums are your friend use them and ask questions. It's not magic, it's systematic, although it does seem magical when you get it right. I have been dealing with 5.0 foxbodies for almost 25 yrs and run HCI/injectors on both SD and MAF. I am by no means the expert on this but I learned the hard way and wish I knew this in the beginning. Without a QH you will at some point want to burn it to the ground and regrow more hair so you can pull it out again! ESPECIALLY IF YOU START FIGHTING AGAINST EEC- IV programming and it will fight you if you don't know your place or the secret handshake! Running and running correctly are two different things. It's a beautiful thing when it is right! Everything else you will hear will be opinion based advice. These are gospel for the foxbody. Try it, prove me wrong and thank me when you can't. Do a lot of researching and a lot of listening. GOOD LUCK and GODSPEED my brother, you are not alone.
 
I love LONG POSTS and appreciate you taking the time and explaining your experience

We are not reinventing the wheel.

I’m not really after a Holley Carb Setup,
But am unsure if the setup I have will work.

I’m kinda hoping it may be better after clearing my codes.

So to be clear now with my setup.
I’ve basically believe that the Car is an 89
(VIN PROVES THAT)
Is the V8 Model (Vin proven)
Now for the juicy stuff
EEC is from a SP setup.(I’m fine with this)
Engine Wiring harness is either 87-88 version
(Fine with that too)

Car will dump codes with my reader (Ford Yellow one)

Car has 1 code left —23 during KOEO
When running it’s in Limp Mode tho(code 98)

This tells me the EEC is communicating with sensors. (A good thing)

SO…..

I have a new TPS sensor in comming (Dealer)
I tested old one and could not achieve any voltage drop below 4V in any position on signal side
5V ref was present as well.

I’m gonna wait/Test and install that

Unhook Bat for 30 Mins
Set base idle
Timing at 10

Then fire up and see.

I should have a bit more info after all that.

Mr Blake!! I Thankyou

And yes I’m that guy who will listen and research the crap out of this to get to the bottom or at least have a good runnin 5.0
 
Well then, you'll love this!
Key thing with Speed density cars is the Map sensor and the vacuum tubing connected from it to the intake manifold. If the are any leaks there you will never get it tuned. Unfortunately without an oscilloscope you can only make sure it has the correct incoming voltage (@map). EEC adjusts fuel and spark based on manifold vacuum or lack there over when you press the right pedal. Have you tried idling it with the tps unplugged? Set idle to roughly 625-650 rpm IAC and spout unplugged 10 degs base timing, factory set point is 672 rpm and it will try to get by any means possible, (birthplace of idle surge) Do this only when car is warmed up above 160 or else the eec will be adjusting down to desired idle speed and timing and your idle will change until up to temp. That will get you close to 25-30% duty cycle on the IAC. That is where you want to be regardless of tps voltage.This and base timing will be key to drivabilty and idle. Think of IAC as a slow trim and timing as a fast trim. EEC will do most of idle adjust with timing and IAC to smooth it out. If you open throttle blade too much IAC will be too low in the duty cycle to react fast enough and you will suffer dying/unable to hold idle, same with TB closed too much, duty cycle will be to high and you might get hanging idle from rev down and surge. Without going down the rabbit hole of the IAC function, just be happy understanding that the fox bodies EEC IV are designed to run off of a predetermined quantity of air measured in kg/hr, it is the same in both SD and MAF. MAF measures this across a heated wire that affects voltage with air flow, SD does this with modulated wave assigned to manifold pressure/vacuum changes (MAP sensor), spark and fuel tables are pretty much the same for both just go about it differently. Ford figured out exactly how much air the TB and IAC flow at base idle of 672 and 25-30% duty cycle and wrote the code for the sensors to follow that as law. This is where HCI and injectors and throttle body swaps get tricky or bad sensors kill you, as with out correct emulator and software you are blindly trying to get back to that magic 20.41 kg/hr at 672rpm TB/IAC combined flow. You can't see duty cycle without a QH, MS, or Tweecer and a laptop and happens too fast to see with a digital meter. It is a pulsed 12vdc signal. Speed density is simplicatally complicated, meaning less parts than MAF cars, but more important to get set right. Vacuum leaks are your nemesis when it comes to speed density foxbodies esp. Give them no quarter. To be effective in tuning these cars you first have to understand why they are unhappy in the first place. Without this understanding, you are simply jerking off. If you both work together the eec platform can do great things, but a Quarterhorse is a must have item if you change anything other than spark plugs and oil with these cars. I know I have said a lot but, each statement was a lesson hard learned, if I can help you to not go thru that heartache, then my troubles were not in vain. Only things factory left in my car are the forged short block minus cam and the axle tube. Nothing crazy but enough to cause headaches with factory tuning. Mine holds 800 ish rpm just nice with MAF conversion and tune. Got too complicated to make happy with SD and no tune. Let me know what you find out with your testing of grounds and sensors. I will try to check back on the reg. There is a book on EEC IV theroy, if you care to dig deeper and EFIdynotuning.com is an excellent resource. I can't understate the need to know why before you try the how, enough. Also, download as many drawings and diagrams as you can find and put in all in one file. Most all of it is in here if you search for it. Thank you for taking the time to read this short post, if I had more time, I would've written a longer one......
 
Also,
Do not run a T-stat element colder than 180, there is no benefit in a untuned car and will only cause more confusion and suffering as the computer will still be in the start up tables for fuel and timing. Especially true for SD cars. There is a reason it came out of Detroit with 190 and that is what I run. It ran great when it rolled out of the factory and it can again.
 
As for your set up. Judging by the high serial # 26,533 it was probably an 88 made after Sept 1st thus labeled an 89. If that is the case then the DA1 Speed Density EEC and harness would be correct. I wouldn't worry over it. Just for giggles drop the glove box door by squeezing the tabs inward and check for a build date written on the back of it. I know some of the later years had it hand written on there. Mine did not, but by decoding the build sticker I know mine was built in July and being a low 20k number that's what make me think yours is a past Aug 88.
 
Well then, you'll love this!
Key thing with Speed density cars is the Map sensor and the vacuum tubing connected from it to the intake manifold. If the are any leaks there you will never get it tuned. Unfortunately without an oscilloscope you can only make sure it has the correct incoming voltage (@map). EEC adjusts fuel and spark based on manifold vacuum or lack there over when you press the right pedal. Have you tried idling it with the tps unplugged? Set idle to roughly 625-650 rpm IAC and spout unplugged 10 degs base timing, factory set point is 672 rpm and it will try to get by any means possible, (birthplace of idle surge) Do this only when car is warmed up above 160 or else the eec will be adjusting down to desired idle speed and timing and your idle will change until up to temp. That will get you close to 25-30% duty cycle on the IAC. That is where you want to be regardless of tps voltage.This and base timing will be key to drivabilty and idle. Think of IAC as a slow trim and timing as a fast trim. EEC will do most of idle adjust with timing and IAC to smooth it out. If you open throttle blade too much IAC will be too low in the duty cycle to react fast enough and you will suffer dying/unable to hold idle, same with TB closed too much, duty cycle will be to high and you might get hanging idle from rev down and surge. Without going down the rabbit hole of the IAC function, just be happy understanding that the fox bodies EEC IV are designed to run off of a predetermined quantity of air measured in kg/hr, it is the same in both SD and MAF. MAF measures this across a heated wire that affects voltage with air flow, SD does this with modulated wave assigned to manifold pressure/vacuum changes (MAP sensor), spark and fuel tables are pretty much the same for both just go about it differently. Ford figured out exactly how much air the TB and IAC flow at base idle of 672 and 25-30% duty cycle and wrote the code for the sensors to follow that as law. This is where HCI and injectors and throttle body swaps get tricky or bad sensors kill you, as with out correct emulator and software you are blindly trying to get back to that magic 20.41 kg/hr at 672rpm TB/IAC combined flow. You can't see duty cycle without a QH, MS, or Tweecer and a laptop and happens too fast to see with a digital meter. It is a pulsed 12vdc signal. Speed density is simplicatally complicated, meaning less parts than MAF cars, but more important to get set right. Vacuum leaks are your nemesis when it comes to speed density foxbodies esp. Give them no quarter. To be effective in tuning these cars you first have to understand why they are unhappy in the first place. Without this understanding, you are simply jerking off. If you both work together the eec platform can do great things, but a Quarterhorse is a must have item if you change anything other than spark plugs and oil with these cars. I know I have said a lot but, each statement was a lesson hard learned, if I can help you to not go thru that heartache, then my troubles were not in vain. Only things factory left in my car are the forged short block minus cam and the axle tube. Nothing crazy but enough to cause headaches with factory tuning. Mine holds 800 ish rpm just nice with MAF conversion and tune. Got too complicated to make happy with SD and no tune. Let me know what you find out with your testing of grounds and sensors. I will try to check back on the reg. There is a book on EEC IV theroy, if you care to dig deeper and EFIdynotuning.com is an excellent resource. I can't understate the need to know why before you try the how, enough. Also, download as many drawings and diagrams as you can find and put in all in one file. Most all of it is in here if you search for it. Thank you for taking the time to read this short post, if I had more time, I would've written a longer one......
short post?? :jester:
 
Hi guys, TPS switch installed,
Code is gone now,

Now it seems the only codes present are Smog stuff and maybe some vacuum issues,
Car idles well, so far, runs well on road.

Just haven’t really had the no start hot issues either, but I’ve only ran it a few times..

We will see I guess.

Now I’m learning about the SD setup as apposed to the MAF.

ALSO, WHEN I HOOKED UP THE code reader, I was given a 6 (cyl)
Then next time a 4 (cyl)

Still a few funky things happening but she’s running