View Full Version : Hard time starting when hot
mmacalus
July 7th, 2015, 18:27
Not sure how familiar any of you guys are with a6's, but mine is having a hard time starting when it gets up to operating temps. I have replaced the crack sensor and checked to see if the fuel pump is priming, which it is. There is no faults in the vag com, so I'm just a bit stomped at what i could be. Any ideas ?
hahnmgh63
July 7th, 2015, 22:46
Fuel filter? Fuel pump pressure, check valve.
kruat
July 7th, 2015, 23:27
How old is ect sensor?
mmacalus
July 7th, 2015, 23:38
Just changed it thinking it would solve it too. But it's weird because once it startes up, it runs and pulls fine.
SteveKen
July 8th, 2015, 00:54
Can you hear the solenoid click to push the starter gear into the flex plate?
If so then it could be a weak battery or bad ground.
On way to troubleshoot is to ground the engine to the body or directly to the negative battery terminal when it's acting up.
Bigglezworth
July 8th, 2015, 01:32
Solenoid on your starter is the culprit. I'd bank my bottom dollar on it.
mmacalus
July 8th, 2015, 01:41
Thanks for your input, I will give it a try.
Bigglezworth
July 8th, 2015, 05:55
Also, you should first ensure you have a battery with good strength and also CLEAN connections. Heat and dirty connections create bad start problems also. Heat and a battery with a bad cell or poor charge also are a problem. I had presummed you don't have a battery problem as those are pretty straight forward to diagnose as the car turns over slowly, or lights dim as you crank, etc. I still believe you should start with the starter.... Best of success with getting to the root of the problem.
Yes, basically the same car sans turbo's. Typically it's going to be lack of residual fuel pressure. Sounds like Vapor Lock symptoms.
Fuel pump check valve, fuel pressure reg. could be bypassing. Replace fuel filter if more than a couple years old.
Last time I saw a fuel pump circuit ran off the starter or oil pressure switch was on domestics.