Hi All,
I have an 88 toyota pickup XCab with the 22RE engine. My truck has been running a little rough on the idle side. It idles from 500 to 900rpms. When my pickup warms up or the weather is hot outside, and i do some in town driving, it idles from 500 to 1500 when coming to a stop. If i have the brake and clutch pushed in at the same time it'll drop to 500rpms then climb to 1500rpms and drop off back to 500rpms. I've taken my foot off the brake, and it stops. The past couple of days it's been dying at stops when i brake really hard.

I've heard that there's a check valve that regulates the idle when slowing down and stopping. It's supposed to drop your idle to 5 or 3 then bring it back to the normal idle level?

Your help is greatly appreciated...this is my daily driver, thanks

 

Your brake booster may have a leak. Plug the port on the intake where the hose connects, step on the brake and see if it fixes it.

Be careful if you drive it like this. You wont have power brakes.

 

I'll try that, but it doesn't always surge when on the brakes and clutch. It seems to do it in really hot weather or a lot of around town driving.

 

i would look for a vaccum leak somewhere, cigar or starter fluid

 

Sounds like either a vacuum leak or bad brake booster.

 

some of the older efi yotas(4x4 only??) have a little breather looking thing that hangs down under the throttle body, at the end of a vacuum hose, if I remember right.

but I don't think that it can raise the idle back up randomly, it's only designed to slow the drop in idle speed when you let off the gas really quickly.

I would do a full vacuum hose inspection, make sure there aren't any leaks, and that the hoses are routed correctly... that includes the intake boots.

maybe check the afm functionality as well, with a voltmeter.