Need dsm guru's help on car not starting

[Demon5spd]

Ok so here's my list of what i have doneso far to try to fix the car, the car cranks perfectly it just dosen't start.

1. tested fuel pressure 38-40 psi

2. tested injectors along with removing fuel rail and reattaching injectors to see if they spray fuel and they do.

3.did compression test got 158 161 159 161

4. replaced ecu twice this time it has a fully rebuilt ecu

5. replaced plugs and wires

6. replaced coolant sensor and repaired wiring

7. performed boost leak test

8. and made sure starter and battery were good.

9. tested ICS and tps everything test good

SO guys i'm really stuck here i've read the forums so many times and replaced everything everybody said, and still no luck the only thing i have left to replace is the CAS and i don't think it's bad since i have fuel and spark unless the cas is not sending the fuel and spark at the right time. not sure i haven't been able to figure out how to test it.

SO i need your guys help here i'm not sure whats left i thought it might be a timing problem but once the car does finally start it runs great all day until i park it for the night and then try to start it in the morning with no luck.

 

[Stainbox12]

Ok, so the car starts every once in a while? Check the fuses, the mpi one specially. Thats the one in a little box, were your positive battery cable is located. Check also the igniter, it may be faulty.

 

[grnchevyz]

Here's a suggestion....you chaged the wires...are they in the right order?

And you said you had spark...you confirmed that? Just making sure.

check the wire order though

 

[Raph]

is your positive battery terminal loose or is it corroded so badly that things work once in a blue moon?

believe me, it happens.

 

[Demon5spd]

oddly enough i have not look at the spark plug order so i guess i can look at that, and i did use a spark plug tester to check for spark.

As for the battery cables there are some what corroded which i have cleaned them the best i can so i'll look into them more.

Thanks for the help guys i'll go check it out.

 

[Arrow_Runner]

When my CAS was dying (I didn't know that's what was causing this at the time, but I digress), my engine would very seldomly just stop firing for a second while driving 60+mph, then it had a hard time starting, then it had a hard time starting and staying started, then it just wouldn't start at all. It would fire once or twice but wouldn't stay running longer than 3 seconds.

That sounds a little close to what you're having, I think you should be able to test the resistance across the CAS to test it, I just don't have the numbers on me right now, but it's in the Haynes manual if you have that.

Maybe someone else can give you the pins/resistance to check for.

Good luck.

 

[SBstar]

Could you give us a little history? Is this something that just recently started happening? Have you checked out this tech guide?
http://dsmtuners.com/forums/showthread.php?t=217951&highlight=diagnose+no+start

 

[chanley talon]

Do you have a logger buy any chance ? If so plug it in and turn the key to the on position and see if the values are all moving around with out the car running?

 

[Demon5spd]

Ok guys thanks for all the help, something weird happened a couple minutes ago the car started hooray.

Odd thing is the car starts and runs great i gave it a test drive and it ran better then it ever has before.

The funny thing is it's the ecu after all i bought a rebuilt ecu from a guy in my town and the car would not start with it and when it did start it ran so bad it would keep dying on me

So today i got bored and i went to the junkyard a got another ecu this one is from a 93 talon awd but it's for a automatic and i know they were setup for smaller injectors.

But with the automatic ecu the car starts right up idles perfect and it pulls better then i could ever dream i installed the other ecu and it won't start with my old one and the with the rebuilt one it won't start either and when it does it runs like ass.

So my question is now is it bad to run the car with the automatic ecu i have a wideband on my car and the A/F ration is perfect well actually a little rich but it runs great .

So can i hurt the car running the auto ecu i wastold it's bad for it but the car runs great, so what do you guys think.

 

[Demon5spd]

Ok guys here's an update

I've driven the car the past couple hours running errands and what not, and the car runs beautiful and the car starts up the first time everytime now.

Finally i get to see what this car is made of compared to my honda it's awesome if i floor it in first or second when the rpms hit about 5000 the tires break loose hehe i love it.

Ok but the only concern i have is that i have a auto ecu in a manual trans car ans i've been told that the fuel maps are different and that the ecu shouldn't work.

But my wideband says that the a/f ratio is near perfect running just a little rich but not bad and i also checked my plugs and the fine no signs of overly rich or lean condition.

So i decided to plug in my old ecu, the car dosent start i also plug in the rebuilt manual trans ecu the car starts after several times and then when it does start it runs like crap.

So maybe the auto ecu fuel maps are just what my car needs, just wanting to see what you guys think.

 

[steve]

Let's start with the number off each of the three ECUs.

Steve

 

[Demon5spd]

thanks for all the help man here's the numbers off the three ecu's

1.here's my old one -MD166260

2.here's the # from the rebuilt one-MD193297

3.here's the on i got from the junkyard -MD165531
this is the one the actually starts the car

 

[steve]

MD166260 - 91 and 92 Federal Turbo MT FWD
MD193297 - 93 Federal Turbo MT FWD
MD165531 - 91 and 92 Federal Turbo AT AWD

The "rebuilt" one must have some problems. A good one should have worked. There is little functional difference between the original MD166260 and the MD193297.

Steve

 

[Demon5spd]

thanks man i took the rebuilt ecu apart and it look good but i'm not sure.

But for the first time since i've owned the car when i went out the side this morning the car actually started i drove it around the block, it ran perfectly and there were no check engine lights so i decided to try the other ecu out one more time with no luck the rebuilt ecu did start the car after about 10 mins and when it did start i could barley keep it running so i reinstalled the the auto ecu back ans it start right up.

So i'm not sure why the car is running so good with auto ecu but i'm not sure weird, so has anyone else ran a auto ecu in there car with any problems.

 

[steve]

One more thing you can check. On the white connector there will be a 4 digit number. It should match the last 4 digits of the E2T number under the part number on the top case.

MD166260 - E2T36574 - 6574
MD193297 - E2T60874 - 0874
MD165531 - E2T36582 - 6582

If the number on the edge connector matches than the case and circuit board match, if they don't then that circuit board didn't start out life in that case and we would have to crossreference it.

Even if this checks out I don't expect you to see anything but the most serious problems by looking at the ECU. Some problems you can only see with a datalogger.

The auto ECU isn't that far off programming wise that it's going to run badly. You just running richer in open loop that a manual ECU would and getting less performance.

A good automatic ECU beats a bad manual ECU anyday.

Steve

 

[Demon5spd]

Thanks man the number's on the ecu cover match the board so it is a true auto ecu i guess i'll run the auto ecu until i can get a good manual run for now the car runs great and i can finally start the car in the morning without fear.

Thanks for the help steve.