Car sputtering after changing ecu.... Any Help would be great....

[S240161]

Well this is the story.....

I have a 92 Talon TSI the car was throwing checking engines and wouldnt start... So I was told that it was the ecu.... I changed the ecu from a MD165530 (stock) to a MD165531 (I was told this ecu would work). I put the new ecu into and the car start right up...first crank..... I took it down the road it was sputtering like crazy and was boosting 14 on my gauge once i touched the gas.... the car was jerking very hard and pouring out black smoke... Does anyone have any clue what the problem could be???

Do I have the wrong ecu in there??

Thanks in advance...

 

[fwdturbobov1996]

Hmm wow. I think you may need a different ecu just to be safe. You were told it would work? Or did you actually see / hear it in another car

 

[S240161]

I was told that it worked.....

Someone told me that you cant use a 90-91 ecu on a 92 car.... is this right??

Also could it maybe a boost leak.... it was doing this with the old ecu to... just not as bad

the car has been sitting for about 2 months now

 

[DSMmania]

Sounds to me like one of the I/C pipes is completely off, check all of your connections, make sure all the components are there. The ECU will work, only a 90 ecu would give you problems but it wouldn't keep it from running, just some tach issues etc. Black smoke is too much fuel, not enough air...go with that and boost leak the car.

Spray some starter fluid around the I/C pipes and the I/C itself while someone keeps the car running, if it picks up the idle and smooths out a bit, that's where you may have the leak at.

Thanks,
Curt

 

[S240161]

Thanks for the info...


The car will start no problem... when I give it gas in Netural or in gear it sputters a lot... Also the car is a auto if that make a differance...

 

[DSMmania]

Also, check that your intake is on the turbo and the MAF tightly, if it's not tight, and off the inlet, you'll get a totally messed up air fuel and it will barely run, and you may not be able to give it gas.

AT or MT, won't matter w/ this issue.

1G automatics had a seperate TCU for the tranny to control it.

Curt

 

[steve]

I changed the ecu from a MD165530 (stock) to a MD165531 (I was told this ecu would work).

The MD165530 is a California FWD AT ECU and the MD165531 is a Federal AWD AT ECU and should work fine. The 91 and 92 cars used the same ECU's.

So perhaps you did blow off an IC pipe. That would explain the sputtering and black smoke.

Steve

 

[S240161]

Thanks for all the info guys....

In the morning im going to go over all the IC piping...

Could it maybe be a boost leak??

How do you check if there is boost leak??

Thanks again for all the help....

 

[DSMmania]

An I/C pipe off IS a boost leak. You need to make a checker that will pressurize your system. Take off the intake, put the tester on the compressor cover, and charge with 20 psi, and listen for any real noticable leaks. Grab some slightly soapy water and spray onto the pipes as well and if a small leak is there they'll bubble up. If you don't have the tester, run the car and spray starter fluid on the piping and if the idle picks up where you sprayed was the leak.

Curt

 

[S240161]

Thanks man... Im going to try that today....

 

[oldman]

Thanks man... Im going to try that today....

Leak tester.

 

[S240161]

Ok.... Now I really dont know what is going on with the car....

I just went out to it today and started the car... I reved it up to 5500K a couple of time and turned the car off and the car was spitting out black smoke and gunk.... it wasnt to oily..... so I put the old ecu back in and it is not having any reving problems at all.... but still is throwing a CELS.... So now im back to square one thinking that it is ANTHERE bad ecu.....