I'm looking at this camry (133k) for a friend of mine, and it's giving me some trouble.

I've got a CEL with a PO420, which is possibly related, but I want to check my other options first. Also the TRAC OFF & ABS lights are on, but my scanner only does engine codes.

Anything over 30% throttle and the car backfires and sputters, I'd think fuel pressure or plugged exhaust, but it will maintain speed once it gets there. Fuel trims are normal, MAP & MAF signals are normal. Plugs & wires look good.

This all leads me to thinking the cat might have melted down, but I've never seen a camry melt a cat before.

I'm going to go drop the exhaust and go for a drive to see if it goes away, anyone have any other ideas? I'm skeptical that the exhaust is going to be my problem.

 

The exhaust was not the problem, So I cleared the codes, and it did not come back.

I forgot to check the TPS last time, and the TPS only ranges from 11% to 71% so now I'm focusing on that.

It's wierd, it gives normal power sometimes above 30%, but mostly it has nothing and just misses. When it is missing the short term fuel trims drop, as expected so I know the fuel system and O2 sensors are working good. It makes it seem like an ignition problem, but I can't find anything wrong with the ignition system.

Do the V6's have MAP sensors, or just the I4? I haven't seen anything that looks like a MAP, and it does not show up on my PID list.

Thanks,
-Dustin

BTW, the shop he took it to wanted to change the MAF, but could not give a reason.

 

Wow, yeah, cat was melted. Fixed that, then retested the ignition, plug wires were bad. New plugs & wires fixed some of the problem. Still pretty bad, so I'm putting in a new TPS tonight.

I hate trying to fix cars w/ no MIL driveability concerns w/o OEM tools

 

Did you fix it by putting in a new TPS?