Hi Everyone,
Since rebuilding my 350 TPI (see signature), I'm having trouble getting it to idle steadily. Right now, it will surge randomly between about 500 and 900 RPM. In effort to troubleshoot, I have done the following...
I installed an AFPR and the pressure is now at 48 PSI. I also installed a new IAC sensor, cleaned the IAC passage, and tried adjusting the torx idle screw. The TPS sensor has also been adjusted to 0.62. Sadly, none of this has fixed the problem and I am at the end of my limited knoweldge

Any info would be greatly appreciated.

Thank you!!!

 

Hello,
Did you ever fix your problem? What was it? I have a similar problem "surging idel" when engine is warm.

 

First, try setting the tps to .54 volts. When you adjusted the idle with the torx screw, did you follow the factory procedure? I would also make sure all the grounds are clean and secure, and make sure there aren't any vacuum leaks.

 

if your system uses a MAF sensor, replace your maf power and burnoff relays. cheap, and usually a good part of the problem. another sensor that confuses things and makes for a messed up idle is the coolant temp sensor. this especially comes into play when the vehicle is warm.

on a side note, u also might want to get one of those obd1 scanner cables for a laptop. they are around 40 and let you watch all your sensor values realtime so you can see which sensor is out of range or malfunctioning. exceedingly helpful

 

Hi Everyone,
Sorry, I haven't been on the board for a while. I'm still having the problem. I've adjusted the torx screw both with the TPS at .54 and .62. I also removed my air foil (and left it off) and cleaned the IAC passage.

I bought a cable from Moates and hooked it to a laptop, but the software seems to work when it wants to.

Any further suggestions would be appreciated.

Thanks!

 

the torx screw for the idle, turn it out a little more to make the idle a little higher...

also, check for vacuum leaks... get a can of carburator cleaner and spray it around on various parts of the intake with the engine running, if the idle changes at all you have found your leak.

 

DON'T mess with the idle torx screw unless you absolutely have to. It's just a band-aid fix. I don't believe a ZZ4 cam requires an idle adjustment.

Find the problem, don't just hide it.

 

Thanks for the replies!

I tried adjusting the torx screw both directions and it didn't seem to help.

I don't know if it is related, but when I turn the motor over I hear a loud pop/click sound. It sounds like its coming from the passenger side to me. Usually on the 3rd pop, the motor will start up. Could that be an exhaust leak?

 

i dont think anyone can tell you without being there with the car....

does the "pop" stay with the car when its running? or just when you are cranking it over?