Author Topic: Revs drop at 4k  (Read 299 times)

Offline GTi_User

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Revs drop at 4k
« on: November 26, 2019, 09:08:51 PM »
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


Offline muff1991

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Re: Revs drop at 4k
« Reply #1 on: November 27, 2019, 11:07:38 AM »
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?

Offline GTi_User

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Re: Revs drop at 4k
« Reply #2 on: November 28, 2019, 05:20:56 PM »
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  :smiley:

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

Offline muff1991

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Re: Revs drop at 4k
« Reply #3 on: November 29, 2019, 04:20:54 PM »
sounded like the crank sensor tbh. glad you got it sorted mate  :happy2:

another win for VCDS then  :laugh:

Offline Pudding

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Re: Revs drop at 4k
« Reply #4 on: November 30, 2019, 05:30:50 PM »
+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!
Black Edition 30 with manually selected cogs, a beefier clutch, some extra boost and them Whiteline thingies, otherwise standard.

Offline GTi_User

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Re: Revs drop at 4k
« Reply #5 on: December 03, 2019, 09:15:31 PM »
Thanks guys  :happy2:

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

Offline Pudding

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Re: Revs drop at 4k
« Reply #6 on: December 06, 2019, 05:12:52 PM »
VCDS is a must for these cars  :happy2:

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.
Black Edition 30 with manually selected cogs, a beefier clutch, some extra boost and them Whiteline thingies, otherwise standard.

Offline svvg

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Re: Revs drop at 4k
« Reply #7 on: December 07, 2019, 08:49:51 AM »
Do you need to code or reset anything  if you swap this out?

Offline Pudding

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Re: Revs drop at 4k
« Reply #8 on: December 07, 2019, 09:21:01 PM »
No it should just sort itself out.
Black Edition 30 with manually selected cogs, a beefier clutch, some extra boost and them Whiteline thingies, otherwise standard.

Offline svvg

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Re: Revs drop at 4k
« Reply #9 on: December 07, 2019, 10:54:59 PM »
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...