Please Help With Idle Problem!

[mbbollman]

I have a 91 325ix and I recently replaced a completely rusted exhaust with a catback stainless from Ireland E. After installing the exhaust the cars idle immediately jumped to 2200 rpm. After reading all of the posts on r3v I went ahead and replaced the coolant temp sensor, idle control valve and cleaned the intake. The idle dropped to about 1800 but it is still way too high. What can I do to fix the problem? Thanks for your help. -Mark

[redhatpat]

Can't see how this is related to the exhaust...

Check to be sure you didn't bump any electrical connectors loose, and check for any vacuum leaks.

Does the idle bounce around, or is it steady?

[Court M3]

also add afm, but yeah don't see how this is exhaust related.

[mitch500]

maybe o2 sensor?

[jlevie]

Your problem at this point may be a result of a previous mis-adjustment of the throttle stop/TPS as a compensation for an exhaust problem.

Disconnect the ICV and adjust the throttle stop for an idle of 900-950rpm with the engine at normal temp. Then adjust the TPS so that the idle switch closes when there's an 020-040" gap between the throttle stop and adjustment screw (monitor the switch with an ohmmeter or test light). When you reconnect the ICV the idle should drop to about 750rpm.

If that fails to result in a normal idle, you may have an intake leak or someone may have fiddled with the idle bypass in the AFM. In the latter case the idle bypass will require adjustment while monitoring the exhaust gas content.

[mbbollman]

The idle is steady and stays, whether hot or cold at 1800rpm. I am planning on trying the adjustment that "jlevie" suggested. I really hope that works. Is it a consensus that I do not need to replace my ICV? I bought one and tried it but I am planning on returning it as it did not fix the problem

Thanks again, Mark