Rpms drop when clutch pushed in!!!

[DSM Chase]

I have had this problem now for months... I cannot figure it out all my link numberes are good. When the clutch is pushed in while changing gears or at a stop light the rpms will drop, Also when i rev it up and let off the gas it rpm drops.... sometimes even shut off . My ISC motor tested good all coils at 29 OHMS...

Also my BOV is resirculated...
7lb lighter than stock flywheel
simulating idle switch on LINK
Link idle setting at 1k
battery at 13.5v

TPS is at 0.68 at idle and 5.0V at WOT so its good?

ECMLINK Log file.... Its towards the end of the log i am driving down the road and then when i go to turn into my driveway when i pushed the clutch in it happend... Im going about 13MPH when it happens drops to around 400-500RPMS then shoots back to 1000...Log is at the bottom In the Attached Files..

Quick video of it rev RPM dropping, does same thing with clutch in or in neutral


RPM Drop ISSUE - YouTube

 

[hocka09]

Post a log.

 

[DSM Chase]

will post up a log tomorrow

 

[MikeSD]

my car is doing the exact same thing you are describing but I am on a much more stock set up than you.
Happened four times tonight so now at stops I have to toe the brake and heal the gas to keep rpms up. Super annoying.

will be watching for a resolution.

 

[AngelOfPassion]

My GSX does this as well and it is completely stock... If I get into high RPM's and just push in the clutch and not change gears the car will just shut off. I just thought this was normal and I just don't do it anymore...

I will watch for a solution as well because I always thought that it was normal for the car to do this...

 

[MikeSD]

Happened to me a 55mph last night by just pushing in the clutch and letting off the gas. Kind of scary and definitely not normal. Nothing like a 4th gear bump start on the freeway.

Gofer suggested it might be a boost leak. Going to try and test that asap.

 

[97gsxIA]

Have you checked your CPS yet? I've seen multiple bad Crank position sensors cause this exact issue. the CPS malfunction code defintely throws a red flag.

If its MAF you should be able to swap it out real quick to check it. Check these two things then let us know if anything changes.

 

[DSM Chase]

It Only threw the cps cel once, it has not come back since, and how would I properly check it?

 

[MikeSD]

mine turned out to be stupid noob stuff. (your problem may be different)
but I did a biss adjustment, got a big boost leak fixed, and I had a spark plug wire coming loose. Not sure if it was one or all or a combo but my car is not dieing anymore.

 

[DSM Chase]

changed plug wires,will see if this helps any, 3G Maf on the way... Will try and get a log today!

 

[CONSIGLIERI]

I am also having the same problem at a stop light...

When my car is at idle, the rpm is normal. But when I press the clutch the rpms drop just a little...

Also if I'm at a stop w/ e-brake on and rev it to 3k for instance, and let the gas pedal go, the revs drop to 600, the car almost dies and then slowly it goes back to my normal idle (900)

 

[DSM Chase]

I hope to resolve this issue for the community, it seems to be a big problem...

 

[97mitzugst]

Time to time this happens to me and so far it's always been a boost leak.

 

[Hesh724]

It wasn't for mine either, I had a 6 puck Unsprung ACT2100 and never had a clutch issue until randomly my car started dying on the highway, Turned the wheel to the left car would die, etc. etc.

My car dies when i turn turn hard left and try to launch "like pulling out into traffic fast" just like goes PUUU for a second then i got to kinda hit the gas and let it catch up a second. i always assumed it was cause i never have more than a qtr of a tank of gas haha. i checked the crank a few weeks ago when my trans was off and no play that i could get? but is the turning left thing a crank walk symptom?

 

[shampoo]

You said no leaks anywhere, but just in case, I came across this from another thread...

"Remove the intake, exposing the throttle body, turn the car on at idle, and cover the mouth of the TB with your hand to seal it. Be careful, and prepared as it will suck pretty hard on your hand. If the car dies, then you have a leak that is in the butterfly plate. If it doesn't, the leak is further back..."

Maybe it'll help someone with their car dying.

 

[DSM Chase]

You said no leaks anywhere, but just in case, I came across this from another thread...

"Remove the intake, exposing the throttle body, turn the car on at idle, and cover the mouth of the TB with your hand to seal it. Be careful, and prepared as it will suck pretty hard on your hand. If the car dies, then you have a leak that is in the butterfly plate. If it doesn't, the leak is further back..."

Maybe it'll help someone with their car dying.

How does the car even run without the intake pipe on the TB? If i have a coupler blown off my car will barely idle...

 

[DSM Chase]

Video
RPM Drop ISSUE - YouTube

 

[Lou98GSX]

try turning the air bypass screw out a quarter of a turn to see if it makes a differance

 

[DorKie83]

I am currently having the same issue with my GSX as well. But only happens when I drive hard and step on the clutch. Driving normally is fine. Gonna look into the Recirculating boosted air issue. My blowoff valve is right after my MAF so that may be the issue hopefully.

 

[DSM Chase]

I dont see were you are coming from with the whole recirculating after the Maf... They come from the factory recirculating boosted air after the Maf.

try turning the air bypass screw out a quarter of a turn to see if it makes a differance

Are you talking about the biss screw on the throttle body?

 

[DSM Chase]

Friday night drags tonight... Did another boost leak test and the only leak i have is the Throttle body shaft seals are leaking like the ones were the throttle return spring is... What do you guys think about the video?

 

[DSM Chase]

After watching the video it looks as if the stock boost guage shows the needle going up while the car is rpm dropping, This points to Dropping Vaccum?

 

[PieEyedPiper]

After watching the video it looks as if the stock boost guage shows the needle going up while the car is rpm dropping, This points to Dropping Vaccum?

The stock boost gauge is an indicator of nothing. Do not use it.

You can inspect your CPS by removing your lower timing cover. I'm not going to color this further with my own biases, but I think that it is important that you check that and your endplay. One usually means the other.

 

[91boostedgst]

Do you have a vacuum leak?

 

[DSM Chase]

The stock boost gauge is an indicator of nothing. Do not use it.

You can inspect your CPS by removing your lower timing cover. I'm not going to color this further with my own biases, but I think that it is important that you check that and your endplay. One usually means the other.

I dont think you guys understand, I race my car everyweekend... I ran an 11 Just last night... I dont think its crankwalk...

let me know what you guys think log has been posted on First post

 

[DSM Chase]

Went to #482 MAF today, same issue...