Got a 93 5.0 that will not turn up!

[cullman]

Free $100,Got a 93 5.0 that will not turn up!

This eng is possesed, every thing has been changed on this engine twice, includeing the short block,heads, upper and lower, comp., harness, dist, IAC, mass air meter, o2 cens, trans and converter, injectors and harnass. the eng cranks and runs fine but when you get it up around 2800, something starts retarding the timing back to zero. Any help or ideas would be greatly appreciated..D.J.

 

[93stangwithmiss]

I've got a 93 with a similar problem. Almost no power after 3000 rpm. Car is stock (no mods) 5.0. Changed plugs, wires, cap, rotor, TPS, fuel filter, ICM, car passes fuel pressure and delivery test, and had injectors flushed. Can't wait until someone answers this one.

 

[wiski]

I had a similar problem, car started up and ran fine, until I put real load on it, then it choked. Don't forget to pull that "little grey plug" BEFORE you time your engine. If you don't you'll have things all screwed up. I don't think the computer could compensate enough for the "adjustment" I made.

 

[aaros]

both 93's huh? i wonder where they fell in the build compaied with the cobras? dont the cobra cpu's retard the time somewhere in the rpm's

 

[HISSIN50]

The SN's (T4m0, et al) puters have a tip-in retard during shifts - not sure if that is what someone is thinking about.

How much is the timing being retarded at ~3K rpm?

good luck.

 

[aaros]

there not sn's they are fox's. im thinking maybe they somehow got the 93 cobra cpu and its knocking back the timeing.

 

[HISSIN50]

there not sn's they are fox's. im thinking maybe they somehow got the 93 cobra cpu and its knocking back the timeing.

I am very much aware of this. I have no idea what you were talking about before when you said:

"both 93's huh? i wonder where they fell in the build compaied with the cobras? dont the cobra cpu's retard the time somewhere in the rpm's."

Yes the cobra computers can leave something to be desired, but do you think two GT's got Cobra computers? I hope they got the 24# injectors too.

I was only supplying information in regard to your post since it seemed as though you were unclear as to what you were posting. I posted the info about the SN95 computers to see if that might have been what your earlier post was about.

 

[cullman]

I have pulled the spout and set the base timing to around 8deg, and wired it to the 302 and the5.0 fireing order, with no luck :damnit: . We have put a brake-out box on the comp and checked every pen for correct voltage and every thing checked out fine. The comp will not flash any codes so what about that? We have had every 5.0 gurue in north Al. try and break the spell, but they all leave scratchin there heads . Every single piece and part of this eng has been replaced twice, includeing the eng itself, and it does the same thing every time. Oh yea, the fuel pump,tank,lines have been changed also and the fuel press has been checked 23 times We have installed 3 different A9P comp on it with no luck, and also installed a Ford Motor Sports harness, still with no luck. There is a green 100 dollar bill just waiting to go to the lucky fellow that can tell me how to break this spell.......Thanks for any help ..........D.J.

 

[stock 92 gt]

pull codes?

 

[93stangwithmiss]

no codes or lights

I don't know about cullman, but my car (doing similar) doesn't have any check eng light or return any comp codes. I'm wondering if we have the same problem considering my car has never been wrenched on and has low mileage (43K). My car runs fine, as long as you don't want to run in the power band with your foot in it. Starts & drives fine, doesn't die, idle is a bit rough. vacuum guage showed no problems (ie sticky valves). Auto trans. Does same thing whether locked in 1st of left in D. Wonder if Cullman checked fuel press under load. That's my next step. Can't figure out if its timing or fuel causing problem. It has to be one of them doesn't it? I was going to take car to the Ford dealer, but now I'm scared. I don't want to spend $500 and have them not find the problem. Oh yeah, car still has stock comp. How can I check to see if its the timing? Car will rev to 3-4K fine in park when not under load. I'd like to check the timing under a load at 3500 but don't have a dyno in the garage just yet.

 

[Zero_chance]

Have you already checked out the igntion components, TFI, etc ?

 

[Mean86GT]

coil?

 

[WLDHRSE]

Could the 8 degrees base timing be the problem? I know stock is only 10 degrees, but I've never heard of anybody (with a relatively stock setup) going down on base timing. Most people jump up to around 14-16 degrees.

Just a thought.

Cliff

 

[93stangwithmiss]

I replaced the coil, control module, cap, rotor, plugs, wires, and tps on my 93.

 

[Black1987Stang]

Heres a few suggections....Just a thought but could the outer ring of the harmonic balancer slipped and now you are really getting wrong timing degrees even though it looks like its at the right spot? Also why did you put it at 8 deg? Put it at least at 10. You said you hooked the plug wires up to the 302 firing order but was it the H.O, firing order?

 

[cullman]

Heres a few suggections....Just a thought but could the outer ring of the harmonic balancer slipped and now you are really getting wrong timing degrees even though it looks like its at the right spot? Also why did you put it at 8 deg? Put it at least at 10. You said you hooked the plug wires up to the 302 firing order but was it the H.O, firing order?

You may be on to something there , I will pull the balancer off and take a good long look at it. The eng has been timed to the 302 fireing order and the 5.0 HO order. The 302 fireing order does not crank and run well. In just an all around average, what should the base timing be set at?....thanks D.J.

 

[VG30DE]

I have my timing at 0 base right now, its not as sensitive as you'd think. I've run as low as 2 degrees retarded, and as high as 22 degrees advanced. It's definately a possibility, though. I would personally suspect a bad MAF element. Also, make sure the BAP sensor is not connected to anything, it should be open to atmosphere.

 

[HISSIN50]

I did not see a reply to how much timing you are actually loosing at 2800 RPM.

I am with VG - running 2* more retarded than stock should make no difference in a situation like this. FWIW, I am running less base timing than he is on the 94 right now.

 

[nosmatt]

stop throwing money at it, and find the culprit.....

the computer CANNOT pull timing out, IF the spout is removed. set the timing to ~ 30-33* initial, and keep the spout out.

how does it run?
if that does not fix it, well then, your comp is NOT pulling out timing....so look elsewhere......cost: free.

hook up a vacuum guage, see where it idles. with a stock cam, you should see no less than 17", and if your idle is over 700, more like 20" at idle. if the guage jumps around, you got other issues... cost: free (if you have tools, if not ~20 bux for a guage)

check fuel pressure while running under load, tape a remote mount guage to windshield (just like dealer techs do) and test drive car (have a passenger watch) you should pick up roughly 10psi @ WOT vs. steady cruise. if FP drops under WOT, there is your issue, fuel! cost: again, you got tools? if not, bout 60-150 bux! (expensive tool) borrow this one if u can

you would be suprised at what a vacuum guage can tell ya.... burned valves, intake leaks, stuck valve/brocken rocker, bent pushrods etc....

how do the plugs look? any dark? any light?
have you checked the conector on top of the fuel tank? they love to melt on foxes....this leads to poor voltage at pump, and under load can make pump crap out, and will never show elsewhere.....bad fp relay can do same thing.... bad ground from engine to chassis, or battery to engine...
lots of places to go here, stop throwing parts at it untill problem solves itself, this is how dealership techs work on some vehicles!!!!!!!!!!!!!!! (6 litre diesels!) you could have bought another with what you have dumped into it thus far man.....

 

[crazypete]

This is exactly why I put a carb on my 91....

seriously.

Strip that f00ker and toss a carb on it. You'll never have posessions or gremlins on the motor again. It will do EXACTLY what you configure it to do, every time. My computer issues got to the point where the ecu would cut the engine at random times and then come back to life a few minutes later only to do it 2 blocks away. That is about that time I got my summit catalog and started ordering carb parts. For all the money you already have and will probably throw at it, just toss up $750 for the whole carbed package.

Check the computer grounds and measure voltage across the EEC's hot and ground wires. This was an issue on mine.