Did a routine headgasket change and installed an STR blockgaurd and ARP headstuds while the head was off. The studs are torqued down to 67ft-lbs and everything mechanical is in check. Only thing wrong is, as soon as i fire up the motor it shoots to 6500rpm and holds there, more or less idles at 6500rpms. This is with the throttle plate completely closed. I thought it may the TPS sensor and i unplugged it. With the TPS unplugged, the motor idles up and down from 1000-2000rpm. With the TPS plugged back it, it shoots back up to 6500rpm.
Anybody ever have this happen or know a fix? I'm going to swap out another throttle body and TPS and see if that fixes it. Other than that i'm stumped.

 

Check for vacume leaks ,pcv valve mite have poped out or your probably missing a gasket somwhere.....

 

I left the PCV valve open since the hose broke off. Even if there is a vacume leak or missing gasket, i don't think it would cause the RPM's to jump that high.

 

adjust the TPS?

needs to read 0.5v at closed throttle...

(i wouldnt expect it to go that high though...)

t..

 

actually - how can it rev that high with the throttle plate closed????

it needs air to rev and if the throttle plate is shut - how can air get into the engine?

sounds weird man!

t..

 

Maybe a mis-interpertation on my part....but you say the PCV valve hose broke off...soooooo it sounds like you have one BIG *** intake leak from this hose. Unless you sealed off that port that the PCV went to (on your intake manifold)....your surely gonna have problems.

Now, if you did seal it off....you didn't state so.

But its a vacuum leak that causes the idle to raise, as the Honda ECU is of the Speed-Density type.

 

I sealed the PCV valve from the intake manifold. It is still open on the black canister on the block directly below the intake manifold though. How do i adjust the TPS?

 

To adjust the TPS, you need to be able to rotate its housing. Since there fastened with break-away bolts, you need to slot them so that you can use a flat head screwdriver to untighten them.

Once this is done, you need a mutli-meter. There are 3 wires that go to the TPS. +5V, output, GND....using your meter, you need to check the voltage between the output and GND wires.

This reading should be .45V @ idle. Adjust as neccasary.

Some people will come in here and say ".45V @ idle, 4.5V @ WOT"....if it ain't 4.5V @ WOT then tough. If you try to get this reading @ WOT, your reading for idle will have changed....and the idle reading is the important one.

 

un plug your idle air control if the car ides down thats your problem