starting and idling issues

[Tnolan]

I own an '87 SR5, 4 cyl, manual trans, with 329K miles. Hard to start on cold mornings, harder to start on colder mornings. No problems starting when it is warm out. Once engine is good and warmed up (30 miles worth) I will stop at a light and the RPM's will surge between 800 and 1200. If I let my foot off the break the idle RPM's shoot up. This will continue until I have shut off the engine and let it cool down. Someone suggested taking a look at the throttle sensor.
Any ideas? Thanks.

 

[bills86e]

The hood has the 3VZE vacuum line config. Check that each vsv line is correctly routed.
There are three metal tubes in center of plenom on pass side that go down on the fender under all those lines to the vsv's.

First http://personal.utulsa.edu/~nathan-b...74layoutan.pdf
Will help visualy.
The VSV are Blue is PAIR, RED (brown) is for Fuel Pressure up and Green is EGR.


The top of the VSV is from the vacuum source and the secondary goes to the item its running.
EGR vacuum comes from 2 vacuum lines to the modulator then from there to the top of the green VSV, From the bottom of the VSV (bleed off filter) goes to the main EGR valve.
EGR only turns on when a cruise or light throttle is happening.


PAIR, From manifold to a one way valve then to of the Blue VSV top, Out to the PAIR valve.
Only turns on during deceleration.
Fuel pressure up, From Manifold to the Red (brown) to the regulator.
Turns on during acceleration dropping vacuum to zero increasing fuel pressure.
Fuel pressure up can be bypassed if the VSV is bad.

More help: http://www.yotatech.com/f116/need-1995-v6-vacuum-hose-help-209069/

Bills86e

 

[541joseph]

Ya I agree sounds like a vacuum leak. May even be your brake booster.

 

[Tnolan]

Thank you. I will check all of this and the link out.

 

[Tnolan]

Can the brake booster be rebuilt?

 

[nevada]

Can the brake booster be rebuilt?

yes, but not without the proper equipment. its best to just replace it if its bad.


that said, you can plug the vac line going to the booster and see if there is any change.

I would also suspect the cold-start injector, or the temp switch. either of those being bad will cause hard starts when cold.

 

[Hyde802]

It could be, but I dont think its a vac leak.

I would start by checking your Throttle Position Sensor. After that, I think you have your idle adjusted too high. Your idle is high, the computer sees that the breaks are applied and thinks you should be idling, so it kicks it down, then revs back up because your idle is too high , then the comp kicks it back down again

Google 22re surging idle..

 

[Tnolan]

All great information. Thank you for the input. I will look into all suggestions. here's a weird one for you. When I pull the dipstick out the idle changes. Thoughts?