this is my first post after looking for the last few weeks, lots of good info btw. anyway here's my truck info. I bought it 2 months ago. It was running perfect when I bought it. 1995 4runner 3.0 4x4 auto 139k miles. Changed the fuel filter right away and ran seafoam through the vac line because everyone raves about it. The problem is (i know they are naturally slow) the truck runs good for a few miles, then when I come to a stop or slow down and start off again, there's virtually no power there. It takes a while to get up to speed and dies up the hills. I checked the vafm by a post on 4crawler. A couple of numbers were out of spec so I replaced it with a reman from autozone. same problem. I replaced plugs, wires, cap, rotor. Same problem. Thought maybe the bad afm clogged the cat, so I gutted the cat. Same problem... I checked the resistace on the oxy sensor, it was like 21ish so I have one ordered a new one and it will be here tues. Does anyone have any ideas of what to do next? I have a feeling the oxygen sensor isn't going to resolve the issue. I'm really close to saying f it, and taking it to my mech. thanks

 

forgot to mention when it loses power the cat and downpipe glow red. not sure if the still will now that the cat is gutted.

 

What's your base timing at? Do you have a CEL or any codes? Knock sensor or wiring failing will act like this. Puts the truck in retarded timing "limp mode".

 

Sure sounds like a timing problem. Of course, that should have been checked before all the parts were replaced, but it's better late than never.

 

I don't know about timing. Don't have the means to check it. If the timing was off wouldn't the problem be consistent? Sometimes I drive it, and it does fine. It drove perfect for 3-4 days after I replaced the afm. Then started again outta nowhere. Also there are no codes.