90 Toyota 3vze fresh tune up.at a idle when I rev it up to about 2000-2500 it misses bad but idles fine and doesn't do it unless I hold the throttle at that position. It will from time to time miss on light acceleration on take off until I floor board it.at around 55 it misses too unless I floor board it it will go away.fpr is hooked up right,mass air flow when unplugged runs like crap so I don't think its that anymore. Just installed a k and n filter in the stock box no change.only time I get a CEL is when I'm in the high rpms but it goes away as soon as I shut the truck off and turn it back on its gone.I starting to see a trend of the symptoms being slightly worse when cold but does it all the time as well.I'm stumped,sorry for my grammar I'm on my Droid.

 

the first thing you need to do is pull the codes.

 

I don't have a CEL on

 

You just said you get a CEL at high RPMs. It'll have a stored code in it.

 

I had a similar situation for a couple of years; finally tracked it down to a large hole in one of the TVV vacuum hoses on the passenger side fender well.

With the engine idling, run an UNLIT propane torch slowly around ALL the vacuum hoses (including the large intake hoses) & listen for a 2-300 rpm increase in idle. That will show you where (if) you have a vacuum leak.

 

Some codes don't illuminate the CEL.

 

I will check the codes and the CEL I get goes away after I shut the truck off so I didn't think I could check it.I do hear a vacuum leak on the passenger side but I can't track it down so I figured it was normal.

 

All codes (whether or not they illuminate the CEL) remain stored and will only clear after removing the EFI fuse (or disconnecting battery) for 30-60 seconds.

 

Ok thanks guys ill check it out real quick

 

I got 12,24,42

 

http://www.4crawler.com/4x4/CheapTri...es/index.shtml

 

Alot of things could be wrong,I'm not thinking the speed sensor would be it even though my speedo doesn't work, I'm not sure what could be wrong with the dizzy.

 

I'd start by testing the igniter and distributor. FSM procedure here.

 

I can't load that link

 

Try it again.

 

Ok ill try that here soon, also on the way home I tried passing someone so I dropped 3rd and it went nowhere and it was acting like it was hitting rev limiter but I could hear it popping in the air box

 

i have what sounds like the same problem, flashed the code and it was showing knock sensor, sadly its under the intake. can be tested from harness connection in cab need schematics for connector and wires. can pin there and attach a scope tap intake with hammer and see if signal is in specks.

 

can any tell me the best way to remove the upper bolt 2nd above slave pistion. im going crazzy.

 

I have been busy working but i tried adjusted the screw on the TB one turn clockwise and I gained some power back and the missing at higher rpms is a little less significant any ideas?

 

Which screw?