legacycentral bbs

Maybe somebody can help me out here

-hen i take up normal and gradually build speed my car is fine, but if I take off hard and hit boost my car like studders a whole bunch or if i downshift and stomp on it, the same thing happens, got me totally cinfused any ideas?

Sounds like you're hitting fuel cut. Check the houses for the boost control solenoids.

MK

where are the boost control solenoids?

The boost control solenoid is on the passanger side strut tower by the air box. It's a verticle cylinder with 3 vacuum lines going to it and an electrical connection on top.

Here's my question though. Does the car pull hard then jerk really hard like the engine missed or something, then pull hard a few more seconds, then jerk again, ect..? If so, that is fuel cut, if not, then you probably have a totally different problem. Does the studder you are talking about feel like the engine is struggling to accelerate, like it's bogged down or something? Or does it just have a severe hesitation like there is plenty of power but it isn't smooth?

The more detailed a discription you can give us about the problem, the more likely it is that we will be able to help you find it.

Right when I get on it really hard it will automatically studder, jerk, thnbe pull for bout a sec or 2, then studder, jerk, pull etc...

That does sounds like fuel cut.

Do you run a MBC, EBC or boost gauge (probably not but I have to ask)?

From most accounts I've heard of if your boost control solenoid goes bad you usually get lower then normal boost. It may be that your wastegate is stuck closed.

Take the 2 vacuum hoses that come from the turbo to the boost control solenoid (IIRC it's the top two) and hook them together. This should make the turbo only run 5-6 psi which is way below fuel cut. If you do this and the car doesn't pull as hard and the jerking goes away then I would invest in a boost controller like a Hallman MBC ($45-50). If it continues to do the same thing as before then your wastegate is probably stuck or the wastegate actuator is bad.

legacy92ej22t wrote:From most accounts I've heard of if your boost control solenoid goes bad you usually get lower then normal boost. It may be that your wastegate is stuck closed.

That's what I was going to say. Wastegate stuck closed.

A faulty hose is more likely than a stuck-closed wastegate.

Subleg4, I recommend picking up a cheap boost gauge. It's good to have in general, and will help you diagnose this condition in particular.