Engine Nearly Stalls

dug320 · Post by **dug320** » Fri Feb 11, 2005 11:15 pm

Not sure why but well letting off the gas and disengaging the clutch my engine nearly stalls. When in neutral I can rev and let off the gas and it never happens.

Vaccum leak? I checked everything but I could have overlooked something small.

Any guesses??????????????

arbskynxnex · Post by **arbskynxnex** » Sat Feb 12, 2005 12:15 am

I would check the Throttle postioner on the carb. IF I remember correctly, when you let off the gas, the TP engages so the throttle comes down slower and doesn't stall. Its in the factory manual as to what it does exactly and how to adjust it, its in the Fuel system section I think.

dug320 · Post by **dug320** » Sat Feb 12, 2005 1:00 am

I thought it could be. I moved it up and down with no change

takza · Post by **takza** » Sat Feb 12, 2005 5:14 am

Think that's the one on the front of the carb that you need to remove the air cleaner to adjust...if I adjust mine to specs it won't idle down right...so I have a similar problem right now.

Might increase your idle speed by 200 RPM or so? I like easy fixes.

dug320 · Post by **dug320** » Sat Feb 12, 2005 12:47 pm

I wish it was an easy fix. I don't have that much time to fix the car right now. But I really need the car to work.

I have a few hours today so I a going to go through the system.

Cheers

dug320 · Post by **dug320** » Sat Feb 12, 2005 3:31 pm

Ran through everything. It looks the vacuum advance is not working properly.

takza · Post by **takza** » Sat Feb 12, 2005 7:01 pm

Lack of vac advance would probably cause that...I couldn't find any aftermarket dist diaphrams though. Might try to get a quote from the online Toyota dealer?

dug320 · Post by **dug320** » Fri Feb 18, 2005 1:09 am

Well I thought I had fixed it. But I think there is some dirt in the vacuum lines. How it got there is beyond my comprhension. I think I will do a vacuum check on the advance.

dug320 · Post by **dug320** » Sat Feb 19, 2005 4:34 pm

I did the test on the advance. That was not the problem.

The stumbling block in solving is the lack of consistancy in the stalling. No exact way to reproduce the stall consistantly.

hornett22 · Post by **hornett22** » Fri Feb 25, 2005 12:24 am

throttle shaft sloppy? the shaft at the bottom of the carb,can you wiggle it ,is it loose? if it is then you have a vacuum leak in a bad location.i usually can match up bushings at the hardware store.you will have to drill the plate out for the bushings.your other option is to find a carb with less miles or a weber.

dug320 · Post by **dug320** » Sun Feb 27, 2005 2:31 pm

I will check it out.

It is so inconsistant and that is what makes it sooo frustrating to diagnose.

:ph34r:

takza · Post by **takza** » Sun Feb 27, 2005 6:36 pm

Check the equivalent gizmos on the 4WD 3AC?

"I have a 87 Tercel that was getting pretty crappy gas mileage and ran very rough, it would almost and sometimes would stall out at stop lights. I took it the Toyota dealer and they repaced two valves on the outside of the motor, the VSV and BSC valves. I never knew they existed before that. After that + a tune up and the car ran smooth as the day it was made, and I got back all the gas mileage (around 40 MPG). If you think you need them I still have the bill with the part numbers."

hornett22 · Post by **hornett22** » Mon Feb 28, 2005 1:00 am

the 4cyl trucks use them too.

Chris · Post by **Chris** » Tue Mar 01, 2005 12:50 pm

I know what a Vacuum Switching Valve is, but what is a BSC and what does it do? Was it added in 87? None of my five Tercels from 83 to 86 have it that I'm aware of (at least by that designation).
Thanks

dug320 · Post by **dug320** » Sun Mar 06, 2005 1:04 am

The only thing close is a TVSV. No BSC