Running Rough

[TurboGirl]

My 90' Laser RS started acting funny after hitting fuel cut for the first time. It now idles and drives like it is missfiring. Occasionally idles and drives normal for a short period of time but then will start running rough again. The check engine light also comes on. I am trying to get a hold of a datalogger to see if that can help me out. I put in new colder plugs and still it runs rough.

any suggestions?

[Jana]

I would list out what you've done to the car so far (for mod's). That will help narrow down the problem.

[CVD]

Sounds like maybe an intercooler pipe blew off?

[TurboGirl]

I have a boost controller, filter, up pipe, spark plug wires, and after all of this happened I put in colder plugs because I thaught maybe I had fouled out a plug or something. I was checking my boost gauge at idle and the vacuum is at 9-10 and that seems pretty low since when it runs fine it is at like 18-20. I was thinking maybe a vacuum leak.

[fmicmatt]

Originally posted by TurboGirl@Jan 3 2004, 01:01 AM
I was thinking maybe a vacuum leak.
I think you're right.

[Iceman]

Do a boost leak test and listen for a hissing of some sort.

[CVD]

Yeah, it deffinately sounds like a blown off intercooler pipe, I would check all of those connections before you start hunting vacuum lines.

[TurboGirl]

I checked all the pipes and they seem good. I don't know why the check engine light would come on though. There is a small hissing noise coming from around the injectors area. I had checked all the vacuum lines around that area and they are good. Do you think it could be like a intake manifold gasket or something of the sort?

[CVD]

The MAS might have come unplugged also, you might want to check that out.

[john]

Do a boost leak test. You are loosing vaccum pressure somewhere. Yes it could be an intake manifold gasket but it could also be several other things. You will find out when you do the boost leak test.

Would a car have less vaccum if the MAS was disconnected? The symptoms sound like he MAS unplugged but I dont see how that would affect vaccum pressure.