Flooded starts

[Thomas L. Parker]

I have a 93 Z, A4, 151k miles, original ignition, injectors and such. No mods.

It has tried to start but winds up being flooded. Waiting about 30 minutes, the car will start and run fine. This has happened about once every three weeks.

There have been no check engine codes.

Before I start throwing parts at it, anyone else have this problem?

Thanks,

Tom

69 Z, 93 A4, 93M6

[Injuneer]

Does is start easier, if you put the accel pedal on the floor when you crank the starter, putting the ECM in "clear flood" mode?

Two possibilities come to mind (but hard to explain why it starts 30 minutes later)....

1) leaking injectors. Pop the fuel rail, pressure the fuel system (do not attempt to start the car) and look for leaks.

2) failed coolant temp sensor providing inaccurate cold start data. Check sensor resistance vs. temperature.

[Thomas L. Parker]

Still no joy

I tried the flooded start routine but it doesn't work. Engine turns over and never attempts to fire. Exhaust is nothing but gasoline fumes. Going to let it sit and try to do some trouble shooting tomorrow.

[Thomas L. Parker]

It might be something else

I was able to get it to start right up today.

I am beginning to wonder if I have mis-diagnosed the problem. My other 93 Z had the same problem years ago and it turned out to be the ignition module. The symptoms on this 93 Z are quite similar in nature.

I am an 8 bit machine in a 256 bit world - I don't forget but my search routine is quite slow!

I will do the troubleshooting with the volt meter in a couple of days and let you know what the results were.

[Joe 1320]

While it won't start, check for spark. If no spark, it's obviously ignition related. If there is spark and fuel, my bet is that the coolant temp sensor is intermittant. There could be other issues too...... ECM, for one.