#4 injector not getting a pulse

[Kelly Brezovski]

I have a 1994 AWD Tsi, I was driving on the freeway when all of a sudden car starts to run rough and no power and check engine light comes on.  Not sure what the problem is after taking it into a garage they tell me my ECU needs to be replaced, they get it too run ok for a few hours by surgeing the circuit(dunno if thats bad or good).

I took it home and got the code off the ECU error 41

I had the coil pack replaced alittle over a year ago, not sure if they replaced the coil resistor or not?(is it part of the coil?).

I've taken my ECU out and everything looks ok no smell.

Anyone have any suggestions? Dont want to be spending alot this close to xmas.

I must say from what Ive seen this board rocks for helpfull people and good advie hopefully you can help me out  

Kelly

[Afshin Eslami]

You can find the ECU error codes here:

http://www.myzero.com/electrical/code.html

[Kevin Standeven]

so I'm assuming you used a logger to determine that it was injector #4 that's not opening. I'd try swapping a different injector in there, like put #3 into the #4 spot and vice versa. If it's the injector at fault, replace. If it's the #4 spot that's the problem, get a multimeter out and start tracing those wires...

[Andrew Steele]

You say the shop said the ECU needs to be replaced, but they got it running "ok for a few hours".  Did you get the ECU replaced, or are you still working with a blown ECU that's been bandaided?

[Kelly Brezovski]

They check for injector pulse with a bulb tester (not sure of the technical name) 1-3 showed a pulse, So Im thinking its not the injector itself?  After he "surged" it ran fine.

 Im still using the same ECU nothing has been touched on it.

[Andrew Steele]

Well, I may be thinking to simple here, but logic tells me that if the repair shop says "your ECU needs to be replaced" - I'd look at replacing it before trying to troubleshoot uncommon issues like an injector that's not running.  At the very least, look at the caps and the resistors.  Are the caps bulging or leaking?  Ever had a burning-plastic smell in the car?  Ever had a funny fish smell in the car?

If 1 cyl isn't firing (no fuel or no spark) you'll notice quite a loss of power.  However, you say the car's running fine...

A) Are you sure the car's running fine?
B) Are you sure you're not getting fuel to Cyl-4?  

If the answer to B) is "yes", see A).

[John Hartman]

Kelly, is there any chance you can find a local board member that you can swap ECU's to see if that will fix it?  Or borrow one from someone that has a few extras?

That will tell you for sure, then you can hit up Ebay, and the DSM boards for another one.

[Kelly Brezovski]

Thanks alot for the replys guys looks like im going to take it into L&R to take a look at it hopefully i wont damage anything driving it there.

I have had a smell of burning plastic in my car but when i took out the the caps look normal not bulged or leaking.

I will let everyone know what happens with it hopeing to get it to L&R by friday.

Thanks again

Kelly