idle likes to drop to around 300-400 rpm intermittently

[aztecz3293]

93 z32 TT so ill be cruising around (aka burning f*** rubber) and all will be fine. As soon as i start to drive responsibly and not laying in to the gas, the car starts dropping idle when i come to a stop, hasnt died yet... but iv seen it drop to 300. I replaced the fuel filter and got better performance (but then again i was still laying into the gas) then i took the car for a calm ride to the store, Bam! Idle dropped again. Help please.

[frapjap]

Welcome to NICO!
Glad to see you're enjoying your Z.

Have you been up on the maintenance? It may be time for a tune up. In addition to the fuel filter, try cleaning the Idle Air Control valve, the MAF, and changing the plugs/wires. You should also check for vacuum leaks by spraying carb cleaner on/around vacuum hoses. If the engine revs or races up, you've found a leak. Visually inspect the suspect hoses for cracks and breaks. If the issue is vacuum related, it is tiny considering your symptoms.

[Ziggy1621]

Yup, clean and adjust the IACV http://www.nicoclub.com/archives/adjust ... level.html ... and welcome to Nico!!!

[ThisIsSparTTa]

Here's another good article on the idle air system: http://z32.wikispaces.com/Idle+Control . I had a similar problem when I had my base idle adjusted too low. Coming to a stop RPMS would drop like a ton of bricks and engine would die. It's important to know that if you're chipped (SZ, JWT, etc) they may have a higher base idle expected. For instance, SpecialtyZ thinks the perfect idle is 900RPM and expects your car to be set that way.