hanman

I have a 85 SE, 13B. Here's the deal:
Replaced the PD with a banjo bolt, no leaks. While I had everything loose, I pulled the injectors and had them rebuilt by RC Engineering. I pulled the intake runners (plenum) loose from the dynamic chamber (throttle body) and cleaned it up. I replaced the lower and upper gasket for the runners.

When I start the car it races up to 3K rpm, then drops like a rock and stalls. I can keep it running if I keep my foot on the gas and keep it above 2200 rpm, otherwise it runs horribly and stalls. Not even a chance of an idle.

Thinking this is a classic symptom of a air intake leak, I pulled everything loose again, used gasket sealer on the upper and lower gasket, tightened the bolts as much as I dared and put it back on. Same problem.
This thing acts like a HUGE air leak, but I can't find it.

Is there anything I am missing? How about a way screwed up TPS?

Any help will be appreciated,
Thanks,
Dave

slorimer

did you forget to plug in the air flow meter. Similar thing happened to me on my 2nd gen.

slorimer

did you forget to plug in the air flow meter. Similar thing happened to me on my 2nd gen.

the7thguru

Um yea...My 13b did that before....but it was kinda sorta cause my throttle/cruise control linkage kinda became disconnected..(IM STILL CONVINCED IT HAPPENED BY ITSELF) HEHE

adssoccer

the EXACT same thing happened to me after i had my injectors rebuilt. as a matter of fact, you were one of the ones who helped me through it. i ended up cleaning gasket surfaces and using gasket sealer. i also replaced all vacuum hoses connected in any way to the intake manifold that i had messed with. and i replaced a few other vacuum lines that were very very old. good luck!

j9fd3s

iTrader: (3)

did you plug in the bac valve? how about the air intake tube, it is multi peice? power brake booster?

mike

FJ

It does sound like a major vacuum leak. A couple of thoughts:

-A problem with the throttle linkage causing the secondary throttle valves to remain open? You could remove the intake air duct from the throttle body and operate the throttle to be sure they close properly. I would oil the throttle linkage shaft anyway, if you have not already.
-You have new o-rings and grommets on the injectors, I imagine?
-It doesn't sound like you removed the lower intake manifold, but if you did the large hose going to the hard line for the brake booster is a good source of vacuum leaks.
-Are the two hoses to the BAC sealing well? If one has a major leak, it will let in unmetered air and screw up the idle.

Do you have a vacuum gauge? My engine reads 18 psi at idle. If I disconnect a second hose at the chamber to cause a leak the idle rises, as it should for a small leak, and the gauge reads 16. If your problem is a leak big enough to cause it to stall, it must be much lower than that. The gauge is only $10.00 or so.
As you have to run it at 2000 rpm or so, I checked and the vacuum is 22 psi.(measured at the central tap on the dynamic chamber, below the BAC.) That may be of help, if you have a vacuum gauge.

If you have not already, I would keep it running at the lowest rpm possible and spray carb cleaner around the gasket and hose areas that you had removed and listen for an increase in rpm.

It's not the TPS, though. You can push in the plunger or disconnect it altogether, and it alters the idle but does not make it stall.

If it's not a linkage or a vacuum problem, I can't think of anything else for now that would cause your problem, considering what you've removed and replaced.

-John.

hanman

Thanks for the advice guys. It gives me some things to track down. I am not stupid about these things, but I am really under the gun to get this car going, so I really do appreciate the advice.
I will keep you posted,
Dave