Serious hiccups at 5500rm, any hint ?

[fade2grey]

if it's not the ignition side of things, then it's most likely the mixture - Strange that it does it in Stock mode - so possibly a small bore vaccum hose etc - basically something which is affecting the mixture like unmetered air in the intake.

A

[Taipan]

Thanks for the input/explanations.

I may not have mentionned it but the car does NOT have hiccups in Stock Mode (didn't made a Vag Com log though).

Nor do the turbos (or whatever causes it) make the strong and irregular whistle at full acceleration in Stock Mode.

On the spark plugs, I made a separate thread Spark plugs for chipped-unchipped.

Eric

[fade2grey]

Hmmm... sounds like the chipped settings exceeds the conditions you have - ie the fuel pressure too low, too low quality etc or the same with boost\timing. It could be as simple as ambient temps too high, or it could be something more fundamental.

One thing which would be handy is Lambda & Exhaust Gas temp readings - that way you should be able to see if the car is running lean on WOT higher up the rev range.

Either way, it sounds like it may be a plan to speak to the guys that chipped it for some initial diags....

A

[sitas3]

Eric, did you get anywhere with resolving this??

[Taipan]

Not yet...

I'm now planning a trip to Germany to have the car audited during a dyno run and try a different code in the same time.

They'll probably look at sparkplugs/coilpacks/MAF to start with (but I don't want to replace all this if useless to cure the prob).

Eric

[Jon]

taipan are you still having this problem, I had the same problem on my last one. ring me during office hours so that I can have a chat with you

[Taipan]

Thanks Jon for the offer but it's been fixed last week [img]images/graemlins/cool.gif[/img]
If you want to know what was the exact cause (nothing to do with a mechanical failure or plugs or coil packs, etc.), gimme a pm.

Eric

[donrs4]

Guess we are all curious about the real cause... we've been kind of suffering with you about the "mystery problem".
d.