goodspeed

My 89TII, has been ideling horribly , really rough and at 500rpms. ive checked and replaced everything, including plugs, wires, fuel filter, oil change, checked grounds, injector cleaner,
The idle still sucks and its it feels funny until you get past 3000 rpms.

I have good compression, Im not loosing coolant, no smoke, buring the normal amount of oil, the only thing I can think of is a vaccum leak, So i bought a boost gauge , hooked it up, Im getting factory boost of 6.5 psi, steady, but at idle or cruising my vaccum is only reading 9? maybe 10?? shouldn't I be getting more, would this tell you that it is a vaccum leak?

thanks

Turbo FB.

My girls 88'TII pulls about 17 on a A/Meter guage.

goodspeed

thanks a bunch!! that really makes me feel better, my stock gauge always goes down to 20, but they are pieces of crap.

I installed an autometer boost gauge also, I've hooked it up in a couple different places just to make sure.....but I cant even get it to read 10....

that makes me feel a lot better.!!!

One other question. the white house that came with the autometer gauge doesn't reach to where I wanted to, I attached another hose to it, but is there an easier or better way? I have a a piller gauge.

Turbo FB.

My girls is also a pillar mount, I used the plastic tube then silicon line to the manifold. Oh and vacume is a good thing. 87'-88' should be between 14 & 18 in. at idle in stock form. How many miles are on your motor? And if its ported it will most likely be less.

goodspeed

i have a jspec with not even 50k on it.
everything is stock, except a drop in k&n filter.

I read 9 maybe 10 on the vac.

gotta be something wrong...i thinking it may be the intake gasket because I've checked every single hose i could think of....

I also went over a huge speed bump the night before it happened, that probably jarred a hose or something loose.

Turbo FB.

It might be a intake gasket, most likely a vac. leak But it wouldnt hurt to do the gasket and O-rings, They start to crack & leak when they get old.

goodspeed

"o" rings? where do I look to check that?

Turbo FB.

Water passage O-rings.
When you pull the lower manifold off youll see them they will come with the new gasket set. If you replace these upon install put a tad of silicone sealant on the back of the O-rings and stick them on the motor and let them sit for 15 min. or so that way when you put he manifold back on the O-ring wont slip out of there channels and get split causing you to start all over again if done this on my old motor, Because I was to impatiant, I got it all back together and it was like someone turned on the gardenhose.

Turbo FB.

There in between the lower intake and the motor be carfull puting these in you can cut them pretty easy, Put a small dab of gasket sealant on the back of the O-rings (motor side) so they will stay inplace while you put the manifold back on. I cut one of these and made a huge mess. If they slide on you they get pinched and the manifold won't seal and well thats a big pain in the azz, youll get water in your intake and everywhere else.