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Maybe someone can give me some help. Just dropped a ZE in my 92 Mazda Mx-3 gs with k8 ecu, starts fine some times but then it will start to idle up and down like its about to die than go back up to normal idle then die back down. Then I'll try to drive the car and as soon as i take my foot of the gas and the rpm drops to idle it will usually die. Can anyone give me some idea on what I should look for? Has anyone had this problem before?

Yes it is probably the most common problem with a MX-3.
It can be one of two problems.
1. a vaccum leak. To fix, just listen for a whistle or whine and fix the offending hose or bad seal.
2. reset the TPS. I think there is a FAQ in the V6 section that tells how to reset the TPS.

i would say its the tps, mine is doing the same thing but im not going to fix it till its ready to go back on the road.

Just save yurself more headackes and get a KL31 ECU. I went through all these types of issues chasing all sorts of quirky issues for 2 years and ended with an egine trying to kill itself by running absolutely rich and pouring out black smoke.....then I finally got the 31 ecu and it was like night and day. Runs great now! Anyways, try re-setting the ecu and TB adjustment screw. I found that to at least stablize the issue you are having now.

K8 ecu with K8 VAF works fine with the ze, been running it for yyeeeaaaaarss, only thing is it may be a lil rich. ECU has nothing to do with ur problem im certain. TPS...VAC Leak or something else...check codes if the Check light came on.

MX3 for dummies im not saying your wrong but i never had richness probs as bad as yours. Could be cause our set ups might be slightly diff

Guess im jsut trying to say that you can get a nice stable idle with the k8 ecu. I ran 14.2 with the k8 ecu and vaf . But be aware ur gas milage will go down.

But now i have MSnS : P no more K8 ecu i love it cause i still can check for codes too.