Engine revs, when throttle applied, feels like it wants to stall, revs drop 100 maybe 200rpms, then rises.

From idle to 4 grand, seems sluggish, from 4 grand up feels great although I THINK I hear a leak.

Just changed out injector grommets, to try to alleviate the problem, but it did nothing, I've double checked every thing, but can't find the source if it is a leak... I don't know IF a leak is causing this or anything else.

I need help bad, car goes to dyno tomorrow and I need to get it perfect!

Mods in sig...

Thanks

Dan

 

Just took it out for a spin, upon cold start it didn't do rev drops.

Took it out for a spin, when it gets to about 3 grand it doesn't want to go any higher, it kind hesitates and then after a few it will rev up and will make boost.

After letting the car warm up, it does the rev drop thing again, also it seems worse under load, when in neutral and revving, the stumble between 3 and 4 grand is not as defined.

The latter stumble is new, it didn't do that untill I changed the injector grommets. Please help, I have less than 24 hours to get this car ready!!

Dan

 

Do a search for the 3800 rpm hesitation.

I believe it's normally caused by a clogged cat or the 5th/6th ports not opening.

 

He has a turbo, therefore he has no 6 ports.
Secondaries not coming online?
Edit: No, you said it's fine above 4K. Nevermind

 

How's your TPS doing? My car does something similar when the TPS gets stuck.

 

Doctor Wozzoom suggests that you check the leading ignition coil. The symptoms you describe suggests that it may only be running on the trailing plugs.

 

That or a vacuum leak (TID is the most common place).

 

1. Fuel Pressure
2. Vacuum Leak

It just so corresponds that these two are in relation.

Check for a vacuum leak from the manifold to the FPR.

 

I'll check all of those within the hour...

I'll get a little more specific if it may help out:

The car's idle seems somewhat sporatic, just now, after starting the car while it sat for maybe 4 hours, it idle'd @ 750, after a quick spin, dead on @ 1500... Its usually high.

Also the 3-4k hesitation only happens under moderate to heavy throttle, not under low throttle (maybe too much fuel? car DOES have to be tuned after all...)

Under boost I think I hear a leak but I can't for the life of me find any leaks...

TPS does act kinda weird, when the car is started its at about 1.5v then when the car reaches temp it usually stays higher than 1.0 for a while, but eventually will makes its way down to 1.0v...

As far as fuel pressure is concerened would it be too high? or too low? and how is that adjusted. Thanks for the input guys, I've been laboring and just keep running around in circles.

Dan

 

Bump

 

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