95 4runner loss of power

[thomasd]

I have a 95 4runner 3.0, just rebuilt the motor. In park in my drive way, it runs fine timings good idles good revs good. Take off in drive and everything seems good untill about 30 miles an hour than all power goes away, rpms drop off to1300 and will not accelerate over ten miles an hour.

[jetwhine]

thomasd,

The first thing that comes to my mind is a blockage in the exhaust system once warmed up and under more of a load than static idle. Possibly fuel contamination and or clogged fuel filter.

[thomasd]

thats what i keep thinkin, maybe the cat is plugged. Ive replaced the fuel filter and every thing else checks out. Thank you for the reply

[thomasd]

checked cat today, all is clear, still no power.

[jetwhine]

thomasd,

How about the muffler? Maybe take it off and see how it runs.

[sam333]

Check your fuel pressure. Have you gotten it to run at all( normal ) since the rebuild.? If not, I would be checking all the basics , valve timing, valve adjustment, compression , ignition timing. Then move on to the tune up stuff.

[thomasd]

i have not checked fuel pressure, but i have checked compression, ignition timing is spot on cheked twice than checked again. it runs really well with no load and the complete loss of power under load is intermittant. i am still stumped though and will probably check all systems again.

[jetwhine]

thomasd,

Have you checked the Throttle Position Sensor? Also did you maybe get a bad batch of fuel? If your cat is good have you looked into the muffler? Sometimes pieces can come off inside and intermittently block the exit.

[thomasd]

sorry took so long to respond, havent had time to even touch the thing. Gonna check fuel preasure tomorrow will post my results. thanks for everyones input.

[thomasd]

Fixed, it was the throttle position sensor. Put a new one on made a few adjustments and she runs like a champ, thank you guys for the ideas.

[jetwhine]

thomasd,

Alright another satisfied 4runner owner.