So my idle has been some what erratic lately. I deceided to mess with my idle adjustment screw. I jumped the connector with the two female spade by the driver side headlight, turned the screw by the passenger shcok tower. Nothing happened, am I doing it wrong or can it be broken?

Also what's the screw that's right by the afm on the intake? And not to mention my intake filter is super dirty, can that be a factor?

Oh yea I drive a 87 TII. Any input would be greatly appreciated, thanks!

 

Replace the filter, then try again.

If the idle mixture adjustment still has no effect, check the resistance of the variable resistor. Specs are in the FSM.

If that is ok, check the wiring from the resistor to the ECU. You should be able to see the same resistance looking into the connector for the ECU (disconnect from ECU first, never hook your ohmmeter up to a semiconductor circuit such as the ECU).

Measure the voltage on the O2 sensor. Should be around .6 - .8v (rich) at idle. If it is below 0.45, the erratic idle may be due to a lean mixture, such as would be due to clogged injectors, low fuel pressure, or a vacuum leak.

 

Ok, thanks for the input! I'm still waiting for a new filter to arrive in the mail. What I'm most concerned right now is the fact that when I turn the adjustment screw, nothing happends! Am I doing it wrong or can there be a chance of it being broken? And to clarify, all of this started to happen after I installed a deck amp and subs. And on initial start-up I heard a "pop" from the engine bay, but I couldn't figure out what it is.

 

Oh yea, I checked for vaccum leaks already. How would I go about to checking for clogged injectors? Granted that they're relatively new. Primary was cleaned when I replaced my secondaries about 7-10k miles ago. And fuel preasure? I have noticed that my idle is less erratic after a fill up. How would I check that?

What sucks the most is, my laptop blew up recently so I'm making all my post, doing research vis blackberry. And its not possible for me to look at the FSM on here. thanks once again!

 

wait, the passenger shock tower? the yellow fuel pump connector? that's not what you jumper to set idle.

 

If the primaries were cleaned that recently, they are probably OK. The secondaries are not on at idle, so they are not an issue.

Rough idle problems are almost always some version of mixture problems. Vacuum leaks cause a lean mixture at idle; various other problems cause a rich mixture at idle.

Check your O2 voltage at idle after warm up. If it is over .45 volts, the mixture is rich. Under .45, it is lean. That may help direct where to look next.

 

Thanks, ill xheck it out this weekend and let you guys know!

Ps I meant jumping the connector that's by the driver side headlight, green 2 spade one. And adjust the SCREW by the driver side shock tower. Does that sound correct to you guys?

 

The variable resistor is on the passenger-side shock tower. You had it right in your first post.

And the screw that is actually ON the AFM is to adjust how much air can bypass the measuring plate. It shouldn't be played with at all.