Revs drop at 4k

[GTi_User]

Alright everyone,

When accelerating in my GTi and approaching 4k revs, the revs kick back and the engine cannot go past 4k rpm. Like it has hit a limiter of some sort. Otherwise it drives fine below 4k. Any ideas on what it could be? This happened in 1st, 2nd, 3rd and 4th gear, also when stationary and reving the engine. Initial searches say it could be the crankshaft position sensor.

Did a scan with a OBD, but no fault codes appear. Anyone experienced similar before?

Thanks

[muff1991]

i used to get this in cold weather, turned out to be a poor, incorrect or corrupt map/tune file. put a stock map on it and its fine now. Even though you dont have a code, i would replace the crank sensor anyway as they're cheap and not that hard to fit. do you have VCDS?

[GTi_User]

Thanks muff1991. Had it sorted by the garage, it was the crankshaft position sensor for me. Done 90k. All sorted and back to running how she should be 

My OBD didn’t pick it up, but vcds did.

[muff1991]

sounded like the crank sensor tbh. glad you got it sorted mate 

another win for VCDS then 

[pudding]

+1 on the crank sensor if pressing the pedal to the floor at 4K gives no more acceleration, but usually there's a fault code to corroborate it.

Unfortunately they're not cheap, £140ish from VW.  Don't even think about using a crappy pattern part for a critical sensor like that!

[GTi_User]

Thanks guys 

Yep Pudding exactly as you described. Need to invest in vcds as I’ve mainly had vag cars.

[pudding]

VCDS is a must for these cars 

Same here, most of my friends and family have VW/Audis so it's very useful.  I can't bear to see people pay £100 for a dealer scan.

[svvg]

Do you need to code or reset anything  if you swap this out?

[pudding]

No it should just sort itself out.

[svvg]

Thanks. I have a flat spot at 4,000 rpm and had put it down to injectors or standard mapping (it a standard unmodified car). It’s fine on WOT - nice and smooth acceleration - but part throttle occasionally highlights it. Slightly lumpy idle too - will have another look with VCDS - but didn’t have any codes...