Jrichker, HISSIN50 one more time plz

[mustangGT85]

first off, i just want to say thank you to these two guys, and the amount of help they have provided me and others on this board. of course there are many others to thank also, but as i search thru threads for answers i see more post by these two guys helping out other board members the most.

but again i have one more problem. i think it just might be the last bug to work out until i can drive my car daily with reliability. but recently i replaced the cap and rotor and spark plugs, car ran awesome for a couple spins around the block, but i checked my plugs and they are blacker than hell. not a caramel brown like they should, but black. obviously, i'm running rich. i just cant figure out why. again its a stock 87 5.0 no mods other than a conical airfilter.

i asked a local mechanic, and he said the computer might be dumping extra fuel into the engine becuase it thinks its not warm yet. thats one possibility. my GF's dad asked someone at his work(another mechanic) and he said, it might be the oil we used(not sure about this, my GF's dad speaks fluent english, but he sometimes gets confused i think with the correct terminology)

so again, the plugs are getting really black, very quickly. and now the engine is starting to misfire a little bit. i can hear/feel it on the rev up.

oh also i have one other question, about the timing. now i've always heard about turning the distributor clockwise for advance and counter clockwise for retarding the timing. and the stock timing is at 10 degrees. what my GF's dad did though was put some white-out at the 10 degree mark and turned the crank by hand until the 10degree mark was inside that little hole(not sure what its called, possibly the timing hole) and when we fired up the car, he checked it with the timing gun and everytime the gun flashed i could see the whiteout mark light up. is this the right way setting my timing? i've always thought you had to turn the distro.

i'm just wondering what you guys think about this. any help is extreamly gratful.

~Steve

 

[dragnazz5.0]

as far as the timing goes. it soundsl like he was just seeing if it was timed correctly. 10* is stock timing. but yes, you would put another mark at say 12 or 14 degrees and than turn the distributor. but that doesnt sound like your problem. i would pull the computer codes and see what you get. it could possibly be that its just the coolant temp sensor. but it could also be a few other things. good luck

 

[mustangGT85]

ahh, you dont say. i think i might have taken that off. kinda by accident. i'm not running any smog equipment or a charcoal canister, and when i took off a hose on the front of the intake manifold(the one that goes to the charcoal canister) i also unplugged a plug that has a connection near the injectors. possibly the coolant temp sensor. maybe thats my problem?

~Steve

 

[mustangGT85]

i thought it went to plug 12, but maybe i unplugged connection 18. i'll double check this when the sun comes out to play.


~Steve

 

[mustangGT85]

ok, i went outside to check this therory, and it seems though the coolant temp plug is pluged in. it is going right into the top of the lower manifold or something right there. do you think i need a new sensor? the clip that holds it down was busted off. it slides on and off. but i dont think that would be the cause of the problem.

~Steve

 

[jrichker]

Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart.

Or for a nicer scanner see http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $35.

 

[mustangGT85]

real quick question about setting up with a test light. i just connect a peice of wire between the STI pin and the signal return pin, then use the aligator clip on the wire and have the test light touching the positive terminal? then turn the key to the run position, right? and this is of course after the car has warmed up.

~Steve

 

[jrichker]

One picture is worth a thousand words... Here's a picture.. Use the top LH diagram and you are good to go.

 

[mustangGT85]

thank you. that cleared it right up.

 

[sunil6784]

What kind of plugs are you using?

 

[mustangGT85]

ok, this is the coolest thing evar! cuz it actually worked. lol. maybe this computer stuff is here to stay. lol

well i got the codes and thru that link yousent i found the meaning for the codes. but i dont see nothing that would make it run rich. heres the codes as they came out:
23
67
85
87
23
67
85
87
then it flashed once long pause
flash pause flash long pause
flash and stopped

code 23: (or): Closed throttle TP (Throttle Position) sensor voltage out of range. Suspect TP sensor.
code 67 (or): Clutch switch open, AC left on, transmission in gear. (i have no AC, and the car was definitely in nuetral)
code 85 (or): CANP (Canister Purge) solenoid circuit failure.
code 87 (oc): FP relay circuit failure- suspect inertia switch, fusible link, FP relay.

this was KOEO, should i do the test again with the engine running? to see if any differnt codes pop up? or will it be the same?

~Steve

 

[mustangGT85]

autolites....25 and i gapped them at a stock gap

 

[mustangGT85]

ok, the KOER test wont work for me. i followed the instructions, but the engine wont throw any codes when the engine is running. any ideas why this might be?

 

[04sleeper]

2 things come to mind on a speed density car with these symptoms right away.

1) Fuel Pressure Regulator: Have you checked the fuel pressure?

2) MAP Sensor: Could cause the car to run rich if it was not working properly or has a leak in the vacuum hose running to it. But you said it did not show up on your code check so....

 

[HISSIN50]

JR and everyone else has ya covered. I initially liked the bad sensor (be it, ACT or ECT). What kind of vac signal do you see? It should be ~18-22" hg at idle.

Do check and adjust the TPS if necessary. If it is reading high, it does not hurt to back it down a little.

JR and others will have more good ideas for ya. I am too tired to think (around midnight is my mental sweet spot).

Good luck.

 

[HISSIN50]

Oh yeah, I forgot to mention (if it wasnt already) that, I dont know about you guys, but I dont use the hole in the timing pointer as my reference point. I use the knife-edge on the right side of the pointer as my sight-line.

Good luck.

 

[sgarlic]

Oh yeah, I forgot to mention (if it wasnt already) that, I dont know about you guys, but I dont use the hole in the timing pointer as my reference point. I use the knife-edge on the right side of the pointer as my sight-line.

Good luck.

I also used that little pointer (knife-edge) to set mine.

 

[jrichker]

Code 23 - Throttle sensor out of range or throttle set too high - TPS needs to be reset to below .99 volts at idle. Keep in mind that when you turn the idle screw to set the idle speed, you change the TPS setting.

Try this... Currently there is some dispute about setting it at .99 volts but anything less is probably OK. All you need is less than 1.0 volt at idle and more than 4.25 at Wide Open Throttle (WOT). You'll need a Digital Voltmeter (DVM) to do the job.

The Orange/White wire is the VREF 5 volts from the computer. You use the Dark Green/Lt green wire (TPS signal) and the Black/White wire (TPS ground) to set the TPS

Here’s a TPS tip I got from NoGo50

When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks. Set it at .97v-.99v, the closer to .99v the better.

(copied from MustangMax, Glendale AZ)

1. Always adjust the TPS and Idle with the engine at operating temp. Dive it around for a bit if you can and get it nice and warm.

2. When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground.

3. Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.

4. Check the procedure for your year, on my 90 I have to turn the idle screw until it just touches the tab, then insert a .010 feeler gauge and give it about one more turn. Then you adjust the TPS voltage to .98v, reset the computer. Start it up, if the idle is to low then turn the screw in until it is just right, then readjust the TPS voltage to .98v and reset the computer and start it up. The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed.


If resetting the TPS doesn’t fix the problem, then you have a wiring problem with the TPS signal ground, the black/white wire that connects to pin 46 on the computer. With the power off, measure the resistance between the black/white wire on the TPS & the negative battery terminal. You should see less than 2 ohms. More than 2 ohms means a bad wire or bad connection. Check the resistance between the black/white wire on the MAP/BARO sensor and then the black/white wire on the EGR and the same wire on the TPS. It should be less than 2 ohms. Next check the resistance between the black/white wire and the negative battery post. It should be less than 2 ohms. Clean and inspect the 10 pin connectors too.

 

[04sleeper]

Oh yeah, I forgot to mention (if it wasnt already) that, I dont know about you guys, but I dont use the hole in the timing pointer as my reference point. I use the knife-edge on the right side of the pointer as my sight-line.

Good luck.

You are correct on that one JT.

 

[mustangGT85]

awesome guys. thanks a bunch. i will try this. just an FYI i went to the junk yard and got a new TPS, and the one i have(currently on the Rx-7) is missing a little circle in the top. the one i picked up from the junk yard isnt missing that little circle. do you think that could of been a problem also?

~Steve