So I had the heads of my 3VZE rebuilt and got it all back together and it was running great, had to do some tweaking, but I had it pretty good. I get in my truck this afternoon to go out and it wouldn't rev past 3000rpms as I was driving. Even in neutral. I changed the distributor cap and rotor, and the spark plug wires thinking it wouldn't hurt to tune some light tune up things, which it didn't. I was tweaking with the TPS and nothing changed, even when unplugged it, so maybe the TPS is bad? I also figured out that I could rev it all the way up if I just hold the accelerator down very slowly which makes me think it could be a fuel pressure issue? Or the ECU is messing something up? Any info?

 

Does it want to stall, or does it cough and splutter atleast, or does it just hold steady rpm and refuse to climb unless under very light throttle? Have u checked for codes? I would think that a faulty tps would throw a code, but cant be certain. Certainly sounds like an issue that could be caused by a dodgy tps. Ita got to be one of 3 things. Air, fuel or spark.

 

It idles just fine, most of the time when I press the gas, it'll sputter then go up 500-1000rpms then cough and keep the same RPMs, but if I hold the pedal very lightly and steadily, it'll climb no problem until I put the slightest pressure more on the pedal, it'll also sputter and die down. I reset the ECU by pulling the EFI fuse then let it run for a few minutes, revving it a little then rechecked codes and I got a TPS code and a VSS code. I unplugged the TPS while it was running, so that might be the cause for that code.

 

Sounds like the timing belt might have jumped
Check your Cam & Crank timing. Make sure they line up properly

 

The cams are still lined up with each other, but I'll have to check tomorrow whether they're lined up with the crank. If it jumped a tooth already, something else is wrong too. I just put the belt on a couple weeks ago.

 

Check the AFM too. I had one on my 22re that would start and idle fine but as soon as you tried to drive it, it would fall on its face and wouldn't rev more then about 2700rpm. The AFM had a circuit go bad in it somewhere. Never threw a check engine light either.

 

How would I check the AFM? I know the flap door is working properly and the engine dies out if I unplug it while it's running. Sucks when most of the possible solutions are $150-200 sensors.

 

There are specs for checking it with a multi meter but I don't know what they are. You could probably find them on here or on google though.
I know when mine went bad, the guy that did my engine for me did this trick.
With the engine running, the opened the air box and stuck his finger up into the AFM and pushed the flapper door open and the engine started to sputter but did not die.
Swapped on a different AFM and when the same procedure was done, the engine died almost immediately. He told me the bad AFM wasn't getting off the idle circuit.

 

I'll try that. Thanks a lot

 

I second the Air flow meter, I left mine unplugged accidentally after some repairs and did exactly as your talking about when I tried to run it. Finally realized my mistake, and plugged it in, ran perfect.