hi.
i have a 93 laser awd.
yesterday i installed a 16g turbo and a evo 3 o2 housing and a 2g tb elbow with a custom made upper intercooler pipe and a 3inch gm mass and the maft computer.

heres my issue.
it passed etest.
but it idleled rough from the day i got it runing.
i installed vac boost guage and af guage yeaterday aswell.

it idels like a tank vry very rough and the idel goes crazy sometimes.
the car at best has like -10 -12 vac at best.
i know my other car was -16.
what can cause this?

i know when i bought the car from this guy in to he didnt have a friggn clue about cars and he lied to me big time.

he told me the timing belt was changed.
i took the upper cover off and looked at the tbelt and it looks newer....still soft black.

the engine has no blow by...0 and i did a compression test 150 150 138 150. its within spec.

could i have a intake manifold gasket leak or something stuppid?
or could it be the timing belt is off a tooth or two.
does anyone have a idea.
thanxs!

Boost leak test...

i had swiss chease in the outlet intercooler but i fixed it and now that the gm mass is right beside the battery it can only be the throttle body or the intake manifold or the gasket.

if not valve timing?

no engine lights or nothing....

Sounds like you should do a boost leak test and check the timing marks.
http://www.vfaq.com

If you don't have the MAF-T set up properly you could have missfire and low vacuum.
Same for any bad ignition components.
Computer, injectors, missing shift keys, etc..

it was runing stupid before any mods.
it passed etest running like a tank.
i will boost test it and then im gonna change the lifters and check the vlave timing.

it was intake manifold gasket....was brittle and full of holes.
i replaced it yesterday and check the valve timing and runs sweet now.