Passat 2002 2.0 ALT engine - Very hard to start from cold

[howard6212]

Hi, I am hoping someone can help me here. I have a 2002 Passat 2.0 with the ALT engine. I am having trouble with starting from cold. The car runs like a dream and starts from hot well enough.
But when I start it in the morning or when it's gone totally cold, it stutters a few times. And then with my foot on the gas it will eventually start. I keep it going for a minute using my foot on the gas to feed it some gas.
It's a bit like starting a car in the old days with no choke. So I was thinking it might be a mixture setting or a sensor?????????
Any ideas?

Thanks

[Toonmania]

Could be the Mass air sensor but you would be best getting a code scan done to be sure, have you got a cable?? or perhaps someone near you could scan your car for you where about's are you located?

[Crasher]

I agree that it should have a fault code read but by money would be on the coolant temperature sensor being stuck on a hot reading.

[howard6212]

Thanks Toonmania, I will get a cable and get the code

[howard6212]

Funny you should say that. I have recently replaced the coolant temp sensor and Fan switch sensor as the fan was always on. That seems to have stopped now but the temperature gauge on the dash is reading very low (about 60) and only come up to about 80 when I idle for ages. Didn't think they would be linked. I will get the fault code somehow, thanks Crasher

[howard6212]

Took the car to the garage to get a code reading and was talked into leaving there for repair. After 2 days, they say I need to get the onboard computer checked. Does that sound right? I collected it cos i need it over the weekend. Can't you just factory reset a CPU.
Is a new CPU something I could do?
They said there was no relevant fault codes?

[scotty33]

The coolant temp sender can fail 'shorted to ground', or it can fail 'open circuit' either of which, will trigger a fault code. If it is showing an erroneous resistance reading, it is giving the ECU duff information on coolant temp, but will not throw a fault code. VCDS can display the data from the ECU temp sender, if the engine IS cold, but the reading in vcds is somewhat warmer, you have your culprit.
The sensor is a 2 in one unit, one side of it handles ECU feed, the other side the temp gauge feed.
If you can figure out which side is which and test resistance when the engine is cold and again when the engine is hot, post up here and somebody may be able to tell you what they should be, no need for vcds this way?