Hi-
My wife's 01 passat wagon (1.8T) has been having warm start problems lately. Car starts fine in the morning but sometimes after a short trip it will barely start. Eventually it does start up and seems fine after that.
We had new plugs, filter, oil change and the battery replaced. Seemed better for a while but just happened again this morning (And i got an irate call at work : -(
Any ideas?
Regards,
Bill
My 94 Jetta GL is having the same sort of problem. It cold starts fine and runs great, but after the engine has had time to warm up, it starts really hard. It will turn over, but almost immediately stall unless I hold my foot on the gas and keep it above 1300RPM. It will continue this behavior until I've driven it a little way and then it idles normally. It doesn't sound like it's starving because it will still rev fine, it just won't idle.
I talked to a guy and he said there might be a bad sensor (something like a cold start sensor) that is supposed to tell the injectors that the car is warm so the car is flooding. I was also wondering if the O2 sensor might be bad because they tell the computer how to adjust the fuel mixture but only after they've warmed up enough to start working.
I haven't tried either, I've been too busy but I was wondering if anyone has any ideas.
Coolant temperature sensor is one place to look. This happened to a friend's New Beetle and I believe he said that was the culprit.
Byr>Hi-
I replaced the coolant temp sensor on my Jetta and it fixed the problem. Go to your dealer and ask for a Coolant Temperature Sensor and the O-Ring that goes with it. It was a quick fix. Took me about
15 seconds.On the 94 Jetta, the CTS is a 4 pin sensor that lives in the water out hose on the top of the engine.
Just a note that if you go to replace the coolant temp sensor make sure you either drain the coolant, or switch it really really fast, get a helper, otherwise you will have a big mess on your hands.
In our '99 Passat wagon 1.8t we had difficult hot starts. Turned out to be the vapor management valve, and was replaced under warranty. I think the dealer said there was an issue with them. That is probably what the other respondent referred to--the engine controller compenstates fuel injection for how much vapor is coming from the evap system (charcoal canister), so if that is screwed up it might use too much or not enough fuel during starts.
We noticed the problem for sure if you filled the fuel tank while the car was hot and the tank very low. Then it would be hard to start. It started, it just took a while of cranking to get it started, just as if it was "flooding".
They also replaced the MAF sensor (under warranty) > Hi-
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