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Engine Stutter When Changing Gears At High Rpm

Douse

By Douse,
in Engines & Forced Induction

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Douse Collaborator

Douse

Posted
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I have a '92 R32 RB20DET, running 196kw.

The problem has appeared since the tune, and I am unsure if it is because of the tune or if there is something else causing this problem.

When i give the car any stick, and change gears in high rpm, the car kinda bogs down and hesitates causing the car to stutter once. After that it revs fine until i quick shift the next gear and it will happen again.

It almost feels like it is over fuelling or something when I change gears....

I could kinda work around the problem by riding the clutch on the change. However, since the new clutch, it doesn't like to be ridden so the problem can't really be avoided.

Is this normal? am I changing gears wrong? is it just turbo lag?

Any help would be appreciated!!!

zebra Grand Master

zebra

Posted
Posted

Sounds like AFM reversion, my car does it too,

its when the air goes backwards out through the afm when the throttle closes and causes the ECU to dump a shit load of fuel into the motor then cuts the fuel when the air stops for asplit second to start flowing back into the engine. What sort of BOV do you use a good plum back one should stop it.

Douse Collaborator

Douse

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Sounds like AFM reversion, my car does it too,

its when the air goes backwards out through the afm when the throttle closes and causes the ECU to dump a shit load of fuel into the motor then cuts the fuel when the air stops for asplit second to start flowing back into the engine. What sort of BOV do you use a good plum back one should stop it.

Cheers man,

Yeah that's what it feels like is happening. I am using a HKS SSQ BOV, so there is no plum back :\

I know my AFM is being maxed out, would getting a Z32 fix this problem?

Douse Collaborator

Douse

Posted
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is your BOV plummed back ? if its atmo, then thats your problem. Changing AFM's wont do anything for this particular issue.

Yeah its atmo.....I wouldn't have thought that it would be a problem..... and why has it become a problem since the tune?

joeyjoejoejuniorshabadoo Grand Master

joeyjoejoejuniorshabadoo

Posted
Posted

different tunes will be dumping different ammounts of fuel...

get a stock bov... mines fine on 20psi, the "stock bov leaks" thing is just bullshit from people that are too embarrassed to admit they really only have the aftermarket bov for the sound :ermm:

not to mention the aftermarket bov is really the only thing many many cops are looking for under your hood :(

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