ecu?

[9SECAWD]

So last night I was driving around in my 93 tsi, and it all the sudden started spitting and popping, died, started back up and it wasfine. The relay under the dash is clicking, and the tach was jumping around. I took the ecu out and its been socketed and repaired once before. My question is, can the caps be bad and not show signs of leaking? They don't smell or appear to be leaking but its showing all the signs of bad caps?

Anyone? ?

 

[cianfar]

From experience my friend 93 GSX did the same thing. There was no leaks anywhere but once he replace the ecu it never gave him any problems since. That was 5 years ago.

 

[9SECAWD]

I'm just trying to figure out if caps are my problem

 

[Arthris]

Take some good pics and post them up. From there we can tell you if its the caps or not

 

[90tsi6bolt]

The vary same thing happen to me about about a year ago. Spitting an sputtering. Went over everything took apart my ecu an found the caps had leaked an destroyed the board. Replace it with me a new one haven't had a problem since.

 

[9SECAWD]

You must be logged in to view this image or video.

You must be logged in to view this image or video.

You must be logged in to view this image or video.

You must be logged in to view this image or video.

You must be logged in to view this image or video.

those are the best i can do for pictures. it doesn't really show,but there is a light "film" over most of the board that i can scratch off with my fingernail? But the capacitors themselves appear to be in good shape?

 

[Arthris]

The film is there from factory. Helps keep oxygen away to prevent corrosion. ## caps look fine. I dont see anything leaking from them. I would double check all connectors on ## engine. Maybe even disconect take a look at them and re-seat them. Its something simple to do. Also was ## cel on when this happened? Maybe check the ecu grounds as well. There right there next to it. Was ## take and relay jumpin around with engine running or off?

 

[9SECAWD]

the car was dieing and then coming back on when the tach and relay were acting up. shooting fireballs out the exhaust and all that. then it would just crank over and not start. After letting the car set for a few min it would start back up. and i didn't notice a check engine light while this was happeneing.

 

[Arthris]

Hmm. Check the connector at the transistor box. Mine use to do something similar and it was the connector partially coming off

 

[9SECAWD]

the only other thing i forgot to mention, is that i noticed it more after i would try and hit boost. I'm running the stock MAF without a filter right now until i can get the gm maf with maft tuned. i would think it could be a bad maf but that wouldn't make the electrical freak out like the tach jumping around even when i'm cranking it over.

Where is this transistor at by the way.

 

[Ferrarieater]

Check your battery connections and all the grounds.

 

[reddragon1]

I'd check the cas.

 

[WES_393]

Check the ICM. It's on the intake manifold right behind the fuel rail. Most auto parts stores can test it. It would explain your jumpy tach and misfire.

 

[cianfar]

check your ISC seem like a few people have this problem with the 1G and wire brush your battery connections.

 

[9SECAWD]

So after messing with this all morning again, I swapped the maf out and hooked up the gm 3 1/2 and MAFT. It hasn't seemed to act up since? Could a bad maf have caused all my issues?

 

[Arthris]

I really dont know. Without a maf signal it would run but like crap. It could be possible that the maf was sending all sorts of screwed up signals to the ecu. If i remember there is a reset signal wire. Idk if its for the ecu or maf. Maybe that was the issue.

 

[9SECAWD]

I was wrong, its still doing it I'm stumped. We took the ecu out and put it in a different car and it was fine.

 

[steve]

We took the ecu out and put it in a different car and it was fine.

That doesn't surprise me at all. So now the question is what's wrong with the car?

 

[9SECAWD]

That doesn't surprise me at all. So now the question is what's wrong with the car?

Its hard to say. we could have just gotten lucky in the other car. sometimes i can drive around for 1/2hr-1hr before it acts up, and sometimes it takes 1 mile of driving. I tracked down i working ECU that a friend let me borrow that i'm gonna try tomorrow, but if the ECU isn't my problem i don't even know where to start.

 

[Arthris]

If the ECU is not the issue Id start with data logging. Data log as much as you can. Could be some sort of intermittent sensor issue. The 1G ecu's will at times not throw a CEL on for something that should need it. So data logging is the only good way to know for sure that you are getting good sensor signals. If everything checks out there, Then its time to get crackin at the transistor block, coil, injectors. luckily there is not much to the Fuel injection system but problems like this can send someone for a loop.

 

[9SECAWD]

i actually replaced the transistor today because i had one, i checked the IAC, checked the CAS, and timing as well. The only way i can explain it, is the car shuts down like you were to shut the key off and turn it back on fast like 5 times It spits and pops, the tach jumps between 0-3000, the fuel pump cycles on an off, and thats all with the car shut off and the key in the on position. It acts like a loose wire or something, but everything looks in order. Someone mentioned ground wires for the ECU itself, i'm going to check those tomorrow. Hopefully i can get it all squared away :/

Well its not the ecu no idea where to go from here. The main relay is the only thing I haven't checked but I took it apart and it looks brand new? I'm lost

 

[9SECAWD]

Fixed it, turned out it was the CAS..