need help... recently purchased a 1989 4runner 22re. Was driving down the road about 45mph truck start backfiring and went into what feels like "limp mode". I know can no longer get above 15mph and its running bad shaking backfiring etc. the only way I can even get it out of the yard is in 4low cause it just wants to stall. it still starts right up and idles fine. I have checked compression, 150 in all four cylinders. I have messed with timing as well as replaced fuel pump, spark plugs, plug wires, and distributer cap with no results. A few people have recommend looking into my AFM but it looks fairly new/ clean so not sure if that would be it. Any help would be great, thanks.

 

Did you adjust/ check the TPS? Distributor? Plugs and wires? Pull each plug wire one at a time and see if there is any change in idle. If you pull a wire and there is no change then you know there's something wrong with that cylinder. Ie, bad injector, etc. I'd start there.

 

ok, yeah ill try pulling plug wires, I did unplugged TPS and start truck and and try and drive but it was still giving same results.

 

You'll need to adjust the TPS correctly or you'll have all kinds of problems. Check out this link:
http://www.4crawler.com/4x4/CheapTri...roubleshooting

 

Check the distributor/pug wires are connected to the right spark plugs. I can tell you from experience, you can switch the #3 and #4 wires and it will start normal and idle smoothly, but have low power. Not as bad as yours. Did the previous owner install new plugs right before you bought it?