87 4runner 22re surging at steady throttle

[rmoore]

Working on an 87 22re in a 4runner and i cannot figure it out!!! It idles good, runs great while applying throttle, but at steady speeds its surging like crazy! HELP!! Searched message boards everywhere and no answers. I put a new OEM TPS sensor and its dialed. Cleaned IAC valve and throttle body. Tried a new MAF. Nothing seems to work. Any help is GREATLY appreciated!!!

[OVRAROK]

Have you tried unplugging tps, and see if it goes away.

[rmoore]

No I have not, but I will. Thanks and Ill keep ya posted.

[rmoore]

So... I unplugged the TPS and it got a miss in the idle (idles smooth normally)  and the surging stayed exactly the same. I also tried pinching the fuel return line and that actually made a little bit of a difference. Still a bit of surging but didnt seem to be as bad. What does it tell me that it still surges with the TPS unplugged?

[OVRAROK]

So... I unplugged the TPS and it got a miss in the idle (idles smooth normally)  and the surging stayed exactly the same. I also tried pinching the fuel return line and that actually made a little bit of a difference. Still a bit of surging but didnt seem to be as bad. What does it tell me that it still surges with the TPS unplugged?

Tps sounds like it's functioning properly.. if unplugged, and was an improvement. I would lean towards bad/ mis adjusted tps.

[Prismo]

Make sure you idle is under 1000 rpm. Look for vacuum leaks

[OVRAROK]

The plastic elbow on air tube has a tendency to crack too.. 

[rmoore]

I checked for vacuum leaks and the intake air tube... All good and no vacuum leaks. Still going down the fuel return road. Need to check fuel pressure.

[OVRAROK]

Here's a good DIY, relatively low cost way of checking fuel pressure
https://youtu.be/0Ehx6-1w4C4?feature=shared

[rmoore]

Well, I did an EGR delete and it cured the problem.