badbob94

Hey guys!

I finally got my 3vze all back together after a total rebuild. its been a long summer!

The good news is she fired right up! She sounds great.

But she doesn't idle. She is running at 2500rpm. Scares the hell out of me.

Some moisture drippn out of the tail pipe. I did not let her get hot. Some smoke comen from the lower end but I would expect that givn new gaskets and oil.

Any ideas? Something simple? Where should I start diagnosing.

Thanks

Badbob

scope103

Where is the timing set? How did you set it?

badbob94

When I did the rebuild I set the crank to TDC and then when I installed the crank pullies lined them up on their vertical timing marks. Tensioned the timing belt and turned the crank 2-4 times to 2x check that the timing was still correct.

I installed the distributer per the instructions in the FSM. Made sure all the timing was TDC and then installed the gear into the head with all the marks lined up.

Would being off a tooth cause 2500 rpm at start up?

Thanks for the quick reply.

Badbob

badbob94

Does the computer need time to adjust?

Should I run the engine, or drive it so the computer can adjust?

do you think the idle need adjustment?

Does the timing change even if the rpms are high. I think I'm around 20 degrees advanced.

Thanks,

Badbob

scope103

I'm sorry, I should have said "ignition timing." Which you say you think is about 20 degrees advanced (BTDC, I assume.)

You need to use a timing light to set the timing. Doing it "by ear" is only useful if you goal is to get it wrong. You need to follow the procedure in the manual to set it. Idle speed is affected by timing.

Fuel trim is "learned," but that shouldn't have a big effect on idle, and none on timing.

badbob94

Just to add this.

When I installed the distributor I check that the crank and cams were TDC. The distributor was installed per the FSM.

At that point I noted that the distributor rotor was pointing at roughly the 11 O'clock position.

I'll doublecheck it today and use my timing light to get a more accurate read on the BTDC at 2500rpms.

I've cranked the rotor down all the way to retard the timing.

Any other ideas?

idle adjustment
stickly throttle cable
dirty throttle body

Thanks

Badbob

badbob94

Update

turned crank to TDC and took off the distributor cap. Pic shows the position of the distributor rotor.

Just for fun I moved it one tooth to the right and one tooth to the left to see if that help it run.

One tooth to the right and she wouldn't start.

One tooth to the left and she ran at 2000rpm and about 30 degrees BTDC.

I'm pulling the timing belt cover to double check the belt timing.

Stay tuned.

Badbob

badbob94

Ok, just checked the timing belt and it is lined up perfectly.

Crank is TDC

Cams both line up on the white marks.

Humm . . . so why is the timing advanced?

And why is the rpm running 2000rpm at idle.

Please post suggests and ideas

Thanks Badbob

oldblue

vacuum leak? binding throttle cable? i wouldn't see timing causing an engine to be able to run that fast. i'd look for a vacuum large vacuum leak or something holding the throttle body open. for that many rpms, a lot of air needs to be entering.

badbob94

I pulled the throttle body to check the cold idle valve and see if there is anything preventing the linkage from rotating.

I noticed the Dashpot has rotated downward and was holding the linkage back about 1/4". Fix that, reinstalled Throttle Body with a new gasket and she runs more normal!

RPM is about 800 at idle and the timing is about 15 BTDC.

However, every few minutes the idle drops and I hear a deep throaty sound come from the plenum/throttle body.

any ideas?

I have NOT bleed the power steering pump.

Thanks everyone for your help. Its nice to have this beast back up and running. Its been a summer long project.

Badbob