turbo, bucking / cutting power

[jims13 6]

alright guys, not this is a question for the vr turbo owners out there..currently my car should be running around 10psi..now it seems to peak at 12-13psi , and it doesnt matter what i do to the external wastegate.

what happens is, you drive along and go to put your foot down, then at somepoint normally mid to high rev range, the car stutters..now depending on the temp outside and the temp of the car , its wither quite mild or very abrupt..

i have a maf clamp, which tbh, doesnt seem to be making any difference..??? now ive been out in the car with kevhaywire, and the afm was shitting itself, so we both agreed that the maf clamp should work..

now , i have a few intercooler holes to plug, and the co on the car is 8% on boost, im gonna be having it adjusted to a nice 4.5 -5 % on boost and im also gonna bring the fuel in a bit earlier to cure the few degree's of knock im currently seeing at around 3000-3500 rpms..

my question is

1. could the rich fuel mixture , be blowing out the spark at high rpms. i.e flooding it.

2. im running ngk7bpre's (i think) what gap do you turb/charger guys run.

3. which way to adjust the maf clamp..its a split second unit.

or any other ideas..

im gonna fit a bleed valve and lock the boost to 10-11psi..but i need it fixed quite quickly for a forth coming track day, where i plan to anihlate some expensive cars.

i cnat afford at the mo c2/stealth software and tbh it runs very well, apart form the jerking.

ideas welcome

jim

[cabrioman 6]

know im not a `turbo chap` but i had the same kinda thing with mine and it was the boost blowin the sparks out .... i ended up fittin 1.8 turbo plugs and gappin them down to 0.6 mm.... worth a try mate

[jims13 6]

thats knda what i was thinking, but i have no proof, ill pop the plugs out after the holiday and take a look.

[kie_dub 0]

Dont know if you have solved this problem mate but use NGK BKR7E. I had this problem and fitted these plugs. What happened was i got the car and serviced it after a month or so and changed the plugs and got vr6 plugs for it not realising it was not running on vr6 plugs due to temperatures. I got in touch with the previous owner and he told me what he used and that he had tried a few spark plugs and those are the best he has used. Fitted them and hey presto problem solved. Another thing, have you changed your fuel for higher octane like the esso or shell high performance one like v power? i put my car on this and it made it run shit, no idea why!

[Bobtrude 0]

cracked coil? have u checked this?

[pops 1]

"i have a few intercooler holes to plug", that`s your problem, hole`s are causing it to over feul

[jims13 6]

oh er, old post renewal..

cars fine, gtoes like stink now..

was the fuel pump.. dieing a slwo death

[kie_dub 0]

was out racing last night and mine was doing exactly the same as this! What is the cause then? Should i get it vag.com ed?

[Bobtrude 0]

Mine too, was the coilpack.

[kie_dub 0]

is the problem visable or did u find it through vagcom?

[FishWick 21]

The bucking is caused by the ECU shutting the injectors down due to the MAF sensor voltage exceeding the 5V maximum.

MAFs are a royal pain in the back side when it comes to tuning VRTs. Remaps sometimes work, sometimes not, MAF clamps sometimes work, sometimes not. It's a bit of a lottery.