I just completed an engine swap for my 86 4x4 SR5 and the engine is all hooked up and no leaks of any sort. When I try to start it, the engine will rev to around 2000 and then drop really low, and then surge up to over 1000 rpm until it eventually dies. Probably 3 seconds of running. I am trying to diagnose what this problem could be. I know I have a funky EGR Tube that could definately use a replacing. Would this effect the engines Idle? I can't wait to get this yota back on the road. Thanks for any help that comes by. Mike

 

Hey, my hunch was right. I replaced it and it fired up and held an idle.

 

I was about to say the same thing. When I re-did my valve cover gaskets, I forgot to reattach part of the EGR system, and mine did the same thing.

Glad it was so easy.