I am getting an RPM spike on shift after 4000 rpms all of a sudden. I press in clutch, foot off gas of course, and then RPM spike. Video below. Thoughts? Clutch is Spec Stage 3+ with only 5k miles on it. I am thinking it is the APS BOV or my tune (e85).. but way the tune all of a sudden?

IMG_0362.MOV (25.9 MB bytes) =>

https://www.onlinefilefolder.com/1s3lnugXpI6U0L

 

I want to say that it is your clutch. But, I am no expert. So, take my suggestion with a grain of salt.

 

Are you sure you're not just leaving your foot on the gas a little bit too long when you clutch in, causing you to free rev? Make a conscious effort to fully lift your foot off the throttle before clutching, just to make sure it's not just you that needs to adjust your driving a bit before going out and spending money.

 

What the idle like the throttle cable could be getting stuck leaving it open slightly. Just a thought.

 

Bov spring too stiff?

 

could poor TB seals cause this?... just a thought

 

Leaky TB seals cause a boost leak but I don't think they'd cause free-reving like this...

 

Saw the tuner this AM.. clutch and tune are fine. No vacuum leaks either. We even compared another throttle body and the spring\tension seem normal. He adjusted the idle stepping in the tune and loosened the throttle cable a bit. Neither made a difference. Seems like something is holding the throttle open.. he is sending me the evoscan log.. the throttle hangs almost an entire second after I shift.. for example, I let off at say 6700 RPM and the RPMS spike the the 7800 rev limiter.. WTF. LOL.

I am going to oil and soften the spring on my APS BOV. The TB seals are WORKS Aperture and not too old. Maybe grease em?

 

Does it happen only when you go WOT? Check that the throttle isn't getting stuck in the carpet if you have any.

 

I uploaded the EvoScan log the tuner sent me... Check out the lines with Log ID 126 to 134. You can see how long it is taking for the TB to close and how it hangs in the 20-30% open range for too long. I am replacing the seals tomorrow.


Justin RPM Surge - Checkout LogID 126-134.37.csv (25.2 KB bytes) => https://www.onlinefilefolder.com/1sp6qiLZIu0Zlj

 

New MIL.SPEC seals resolved the RPM spike issue.. I noticed my idle went up about 500rpms with the seals change though.. Not seeing a bind in the cable.. Idle is around 1100 and then drops to 900 when fan kicks in, back to 1100 when fan starts back up.

 

could be the bov spring..

 

Really. how so?

 

If the spring is too stiff, it will open up later and won't dump as much air. Kinda like having your foot still on the throttle.

 

Exactly... Try a softer bov spring