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So just like the title says, this is my last effort before I part the Mirage. I have tried countless suggestions, ideas, spent yet another day in the garage with no results. This project has been a work in progress for over a year, and today......I decided that the progress is lacking and therefor its time. Pertinent build info: 6 bolt 63t with moderate rebuild, EVO3 16g, 560's, walbro 255 (rewired), AFPR, 2g MAF, full 3" exhaust, lots of other things that shouldn't have a big affect like I'm experiencing.

Here is where she stands and the list of things I've tried thus far. I have a stock 90 ECU as well as a 92 socketed EPROM with a custom chip that I recently had burned by a very reputable DSM'r. Stock ECU makes the car run fairly well but still not like it should. 92 ECU (w/ pins swapped) makes the car run but won't rev past 2k and stumbles and dies.

Running 2G MAF, so I checked my wiring several times over and it seems to be just fine. Swapped out several different MAF's and no results.

TPS test's out fine. I have not swapped out for another one yet but according to the logger it seems just fine.

Fuel pressure is at 43.5 on the AFPR (at idle). I can take the pressure down to stock and I get worse results.

Unplug each injector as well as pull spark plugs individually......all cylinders fire.

CAS 180 out? Rotated it, then swapped for another one. NO RESULTS!

No boost leaks. Besides, one ECU works well and the other doesn't. I would assume similar results if I had a leak.

Timing marks are spot on. Have not checked with a light but I get same results no matter where the CAS is placed.

Coolant temp sensor is working properly according to logger.

AFR is at 10.5-11.5 at idle and when revved to the minimal 2k rpm it jumps to 20.

So at this point, if I can't get this sorted out I'm gonna part it out. I'm upside down in this build and I have no desire to put anymore money into it. Any thoughts or ideas at this point would save this thing from death and destruction. Thanks in advance for any suggestions.

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2012 Explorer Limited
1989 Colt GT clone 4G63t auto
1992 Talon TSi
1990 Talon TSi
1995 Crown Vic
1993 Ford F-250 BBF
1987 Chevy Sprint Turbo

I assume you have the big silver box (about 1"x1"x4-5") which is the injector box.... to me 10.5-11.5 idle is way to rich.(too much gas)...and 20 is way to lean (lack of gas).. sounds like a wiring issue..or bad tuning issue..

sounds like at idle the injectors are opened and flowing constantly (which they shouldnt be).. and as soon as u give it gas they shut off..(which is backwards).. before parting the car I would try to double check all the wiring..you might have a broken or bad wire..or something might be plugged in backwards like that silver box or the inj clips (if there not stock ones)..

hope this helps somewhat..



doing the swap can be tricky.. not many can get it the first time.. I have done 3 now and still run across issues.. my 2nd swap which was my car took me hoursss to figure it out... I had the inj box and something else swapped.. they have the same plug so I didnt think it was the issue till I swapped them..and it ran good after that.


Steve

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Steve 89 colt 2.3 stroker stock top end. evo3@20 psi 13.489@99.30mph 3/10 2012
On drag radials.auto trans.launching @ 5 psi and no traction thru 2nd.

What you're saying about the injectors makes sense. The car itself is a factory 89 turbo so it wasn't exactly a difficult swap. And it is my 3rd one as well. I'm just stumped on this one. I've got a friend coming by to lend a second opinion, but I'm still searching for the answer at this point. However, I did swap out the TPS and had no luck. Thanks for the input Steve. Greatly appreciate your time and advice.

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2012 Explorer Limited
1989 Colt GT clone 4G63t auto
1992 Talon TSi
1990 Talon TSi
1995 Crown Vic
1993 Ford F-250 BBF
1987 Chevy Sprint Turbo

What does it do on a stock 90 ecu? What are the problems it is having with the 90 ecu? What does it do exactly at 2k that makes it stock revving? It sounds like the issue is coming from using an old tuning solutions to me. If you want to run a 2g mas and 560 injectors spend a little cash and get v3 lite to tune it with. Personally I would try to put stock stuff to match the 90 ecu and see how it runs then.

Well I hate to be the one to say it, but.....these brand new platinum plugs I installed 6 months ago are about worthless. Just for grins I installed some ol' NGK's and who knew, it would be something that ridiculous. I guess after all this time beating my head off the wall it was something very minimal yet very important. Thanks for the help guys. Now I can move on and quit my whining.

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2012 Explorer Limited
1989 Colt GT clone 4G63t auto
1992 Talon TSi
1990 Talon TSi
1995 Crown Vic
1993 Ford F-250 BBF
1987 Chevy Sprint Turbo

yeah NGK's or nothing... and i heard on a turbo motor you DO NOT!!! want to use the multi lead plugs like E3's.. not sure exactly why tho..


glad its running now.

Steve

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Steve 89 colt 2.3 stroker stock top end. evo3@20 psi 13.489@99.30mph 3/10 2012
On drag radials.auto trans.launching @ 5 psi and no traction thru 2nd.

I never run gimicky spark plugs; I have personally seen the horror stories just as you explained. One of my favorites was a Sportster build with some queer "Screamin' Eagle" spark plugs. After all the engine modifications and the entire build were second guessed and scrutinized to death, it turned out to be the new plugs that made it run like a bag of a$$holes.

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"A good day racing is better than a great day fishing!"

Make the computer see what it needs to to start working the logic it needs. That includes putting base fuel pressure to base, 38 psi with pump runnin and hose unplugged. Check maf. Make sure honey comb is in it and it is unhacked. Also maf wiring.

Running at 11.0 is way too rich at idle. Afr goes dead lean when misfire starts due to the excess unburned fuel and unused oxygen. Same as it would read with key on and engine off, lots of air. Is bov recirculated? Or vented to atmosphere? What codes? Do you have a logger of sorts and can see coolant temps? The cluster sensor is different than the ecu sensor. And when failed can cause an excessively rich condition due to the ecu thinking its -45dg.
Last but not least, boost hose undone. Meaning a massive unmetered air leak.

5 things to check and adjust for free. And can be done in under an hour.

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If speed kills, then i shoulda been dead awhile ago. There is no such thing as "Too Much Power". There is no excuse for a lost race. Do you view the rev limiter as a fun limiter?or as a shift point? And we all know, more boost=more fun.

LOL.. good info but he figured it out..it was bad spark plugs.



Steve

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Steve 89 colt 2.3 stroker stock top end. evo3@20 psi 13.489@99.30mph 3/10 2012
On drag radials.auto trans.launching @ 5 psi and no traction thru 2nd.