View Full Version : @@@ Warm Strart Up Issue??? @@@

10-06-2006, 10:16 AM
Hey Guys,

Looking for some help here. I have a 2000 atw runing unitronics, but I dont think software is the issue here since car was acting fine for few months while runing that file.

Any way my car starts up 100% when cold, but when I'll get it to the normal water and oil temperature and shut it down and leave it off for let's say 30mins and then try to start it up, that's when the issue arises, it really struggles to start(sometimes needs to crank for good few seconds), but when it does start it runs fine.

I already changed the water temp sending unit, maf readings seem normal, spark plugs and coil packs are new, not sure what else could it be.

Please advise.


10-06-2006, 10:26 AM
I have heard of this same problems with cars running nothing special as well. Some members had issues when stopping the car or refueling. Hard start afterwards.

10-06-2006, 10:31 AM
i heard some else mentioning secondary air injection system might be causing this, but how do I check that if I dont even get any codes.

10-06-2006, 10:42 AM
I had the same problem, I can't remember what the hell sensor it was..really cheap fix like $22 for the part. This is going to bug me now

10-06-2006, 10:43 AM
Originally posted by SoleMate
I had the same problem, I can't remember what the hell sensor it was..really cheap fix like $22 for the part. This is going to bug me now

Coolant temp sensor... If you have a black top sensor you need a green one...

10-06-2006, 10:47 AM
see I did change that, it was black now it's green and it didn't help

10-06-2006, 01:26 PM
What injectors are you using?

10-06-2006, 01:46 PM
Delph/Lucas (racetronics), 440cc 42lb

Injectors (http://www.racetronix.com/621031.html)

10-06-2006, 01:49 PM
Did you have a cold start issue before?

Don Supreme
10-06-2006, 02:22 PM
Ahhh I just happened to be on vortex and someone just posted your same problem, but on a 2000 passat (probably ATW too).


10-06-2006, 03:30 PM
thanks I'll look into it

10-06-2006, 05:47 PM
Although im NDBW, i have the same problem as well. I am also running unitronics~

10-06-2006, 06:09 PM
Hey guys. I had this problem too. Pretty sure i fixed it.
I changed out the coolant sensor, didn't help. Thought it was my tuning but found enough old posts of people with the same issues and different tuning so i couldn't blame that anymore. I changed out my fuel pump and haven't had a problem in months. Don't know why it would only happen when warm and i didn't even change the pump to try and fix the issue, it just happened to immediately follow. As mentioned by someone else, my car wouldn't start right away but once it did it slowly came up in rpms then ran fine. Just a suggestion, maybe it'll work for someone else.

Don Supreme
10-06-2006, 06:47 PM
good info audi luver...

Marcini needs a HIGH FLOW fuel pump anyway.

10-06-2006, 07:39 PM
Replacing the fuel pump solved a problem I had, but it was the reverse of your symptoms (struggled to start only when cold). If you've never changed it you might be due anyways...

10-06-2006, 08:14 PM
What mileage are you guys at that changed the pump?

10-06-2006, 09:06 PM
I did change the pump already when the symptoms started, i'm runing 255lph, but that didnt help.

10-08-2006, 08:18 AM
Anybody got any more clues??

10-08-2006, 09:36 AM
well one way to see if it's fuel pressure related would be to hook a gauge in and look at it before you start it. that would get annoying but then you could see if was loosing pressure and thats why it wouldn't start. There's too much related to just guess.

10-08-2006, 09:43 AM
i do have a fuel pressure gauge installed, and the pressure before start is where it's suppose to be, so it's not the fuel pressure.

thanks for the advice though