my 93 yota with a 22re began loping(jumping from 1500 to 2000rpms and back) at idle yesterday but stopped after the truck warmed up, today when i started it while it was warming up it began loping again and hasn't stopped even after the truck warmed up the only way i could get it to stop was to turn the idle screw all the down and then the truck is still idling at 1000 rpm which is to high it should be at 750 all my vacuum lines are still connected and don't look to be cracked any other ideas as to y my truck is doing this?????

 

I have a 89 3vze that just started doing the same after a head gasket job. I think I may have the ignition too far advanced and its doing funny things to the cold start assist, or an O2 sensor perhaps. Not exactly sure yet, but the weather should be pretty good tomorrow and I'll dig into it. I know our motors are not the same, but perhaps my efforts could provide some insight.

 

Is the coolant level full? Try burping the cooling system.
Put it in correct ignition time, turn the idle down, then re-time, then adjust idle, then time, etc, until you get it right.

 

88 22re mine does the same thing about once a month

only when i stop and idle it will climb to 2000 then drop to 1000

when this happens i clean out my throttle body and get out the mass air flow sensor cleaner and spray it into the Throttle position sensor hole on the inside of the throttle body

this always stops the idle problem it does come back about a month later but this quickfix works until i get time to work on my truck and figure out the problem

 

Anyway you could post a couple of pictures of how to clean it because mine does the same thing

 

Something else to look at would be that little O ring around the idle adjustment screw. I know the get hard and brittle after a while and may cause a minor air leak. Had this happen once and swapped it for a different screw with a better ring on it. I think you can still buy the O ring at a parts place.

 

ok ill post some pics as soon as i can

 

you getting any codes?
scribed

 

OK, so I did some work to the 3vz today trying to amend my loping idle issue, and had some luck. I was getting a code 25 and 26 which could be a whole host of fuel and ignition problems, so I started isolating variables. I did plugs, wires, distributor cap,rotor, fuel filter, adjusted the idle down from 1,200 to 750ish and cleaned up some shotty wiring from the previous owner. I reset the EFI by pulling the fuse and 20 miles later all was well. I hit the autocar wash on the way home and let it idle the whole time and it purred.

 

thats great...im still getting code 31, tomorrow i will try to jumer the VC and VS lines from the VAFM directly to the ECM, hopefullu that will fix the issue.

 

thanx every one

 

thanx:wabbit:

 

Update: I was getting code 25 and 26 and it was cured with an O2 sensor ...now my idle is a little low but I'm getting 15.8 mpg.