High idle

MX-3 Money · Post by **MX-3 Money** » September 12th, 2005, 8:52 pm

My car will sometime idle around 1500 rpm, when my normal idle is around 700-800rpm. Now I know that when the car is warming up it idles higher but even on cooler mornings it starts off at 700-800rpm. Then as I stop at lights it will idle around 1500 only sometimes droping down to normal after 20 seconds. Maybe it has something to do with my coolent temp sesor or something. Maybe my tb is screwed. Any ideas.?

jschrauwen · Post by **jschrauwen** » September 12th, 2005, 9:01 pm

TPS adjustment, sticky throttle cable, vaccum leak, sticky VAF, water thermosensors, funky IAC. Brad, what things have you checked already?

MX-3 Money · Post by **MX-3 Money** » September 12th, 2005, 10:05 pm

Guess i should have listed them eh? Done the TPS adjustment, pretty sure its not a sticky throttle cable, i'll have to check for a vaccum leak,sure isn't a sticky VAF. Now sad to say I don't know what these last 2 are, water thermosensors and funky IAC.

jschrauwen · Post by **jschrauwen** » September 12th, 2005, 10:38 pm

MX-3 Money wrote:I don't know what these last 2 are, water thermosensors and funky IAC.

IAC - little black cylindrical item at bottom of TB with a 2 wire connector that adjusts for high idle kick-down on cold engine starts. Your TB should have 2 coolant lines running to it (one in and one out) and this IAC measures that coolant temp. I believe the ohms reading (engine off) should fall between 12.5 and 13.3 ohms. Mines toast with a reading of 12.6 ohms so i just disconnected it. Mine is a garaged summer car so cold weather starts for now unitil I get a new TB is not an issue. Try running with it off ( just for shits n giggles) after you've checked the resistance values - confirm those numbers with the on-line manual. Coolant thermosensors - one black and one green one on either side of coolant filler neck. Make sure connections are good and possibly take them out and clean the corrosion off the copper node - be carefull not to break the plastic connector when placing socket over to remove - they're very brittle - and use a copper crush washer when re-installing. Oh ya, go back and check all the vaccum lines, and rubber intake boot for leaks if still using the oem intake.

MX-3 Money · Post by **MX-3 Money** » September 14th, 2005, 3:00 pm

Ok let me ask you this. Say you are costing to a stop light and throw it in netural, do your rpms drop right to your normal idling rpm? Or does it stick around 1500 and then only when you are fully stopped does it drop to a normal idle speed? Cause thats what mine does. How would i disconnect the IAC?

mazda_95 · Post by **mazda_95** » September 14th, 2005, 5:36 pm

do you have a C.A.I

craigco79 · Post by **craigco79** » September 14th, 2005, 5:52 pm

I've just done the KLZE swap, and I have the correct ECU. It had a crappy idle, so change the MAF/VAF, the one I got on EBAY came it doesn't seem to idle better and I noticed the part numbers are exactly the same, I'm not talking bout just the JE50 on the sticker, what are some differencesin the 2, resistance #s, size, whatever.. not wanting to get F'ed, please help!!

thanks
-craig-

hgallegos915 · Post by **hgallegos915** » September 14th, 2005, 8:20 pm

Mine doesnt idle right either after installing a cai... this is with my straight neck...I resolved my vacum leaks and also my sticky throttle. i have the screw closed all the way down..

Tunes67 · Post by **Tunes67** » September 14th, 2005, 8:49 pm

Say you are costing to a stop light and throw it in netural, do your rpms drop right to your normal idling rpm? Or does it stick around 1500 and then only when you are fully stopped does it drop to a normal idle speed?

Oddly enough.. my RS ATX does something quite similar.. when coasting to a stop.. even when just barely moving.. the idle sits around 900-1000 RPM.. but as soon as I stop the car completely (whether I use the brake, e-brake or just let it finish coasting to a stop) the idle then drops down to the normal 600-700 RPM. Granted I have no start up idle issues and I also havent tried putting the ATX in neutral to see if it would do the same thing (might have to try that).. but my car has done this since the day I bought it.. figured it was normal operation of the car.. since I didnt have another MX-3 to reference. Be interesting to see what you come up with on this one

Tunes67

MX-3 Money · Post by **MX-3 Money** » September 14th, 2005, 9:19 pm

Well I just wanna get a whole new TB, I guess a new 68. One of my tps bolts broke off when I was adjusting it. Now it is held on with the one but i'd like to get a new one. I also have my screw all the way down.

jschrauwen · Post by **jschrauwen** » September 15th, 2005, 12:32 am

MX-3 Money wrote:Well I just wanna get a whole new TB, I guess a new 68. One of my tps bolts broke off when I was adjusting it. Now it is held on with the one but i'd like to get a new one. I also have my screw all the way down.

Brad, you'll get a tonof info if you go through mine and Tunes past threads wrt idle, idle adjust, TB overhaul/cleaning etc.
craigco79, there's currently a thread running wrt different VAF applications. With the ZE you should be running a KL31 or KL36 ECU with the original KL08 VAF - JE50. There are alternative to try if you want to speculate, but it should be noted that the KL's, ZE included do run fairly rich - factory intended. Another possibility is to run the 626/MX6 ECU - KL01 with the KL02 VAF. Both the JE50 and the KL02 VAF's look completely identical and fit the same (same dimensions). As to the difference in readings they give to the ECU - good question. I should try a test between the 2 that I have a see what I come up with. Don't know what results will be acieved if you swap out the VAF. Like I said there's a current running thread with someone trying some variations with ECU's etc. Good Luck

Brad, how the hell can you bust a bolt - the TPS housing is plastic. Anyway, try an easy out or small drill and re-tapp. You don't want to try to buy a new KL68 - $$$$. You know, I don't think one could go to Mazda and order a KL68. It was a J-Spec item. The North American Millennia IM's came with a KL47 TB I believe. If it were me, I'd take the TB to a professional if unsure how to fix broken bolt. Give them the second bolt from the TPS so they know thread size and pitch. Shouldn't be too costly at all. After that send your TB out to get bored if you haven't done an overhaul on it. Again, without repeating myself, go to my older thread of about 4 moth's or so ago and then go from there.

Good luck guys,
John

MX-3 Money · Post by **MX-3 Money** » September 15th, 2005, 1:23 pm

I have no idea how that bolt would just break. It must have had a crack in it before. I couldn't even get in that tight to get a good grip on the wrench to put that much force on it. I would like to get the tps back to factory standards cuz I don't think i've helped my idle at all. I would like to get it bored also. Would a kl47 fit my curved neck and would it lower the proformance?

hgallegos915 · Post by **hgallegos915** » September 15th, 2005, 8:08 pm

I got a new throttle body and walla... no more high idle...it was running lean..manifold was getting really HOT you would burn yourself if you touh it..after the tb..i went for some hard driving and manifold was hot but not as hot as before

I could touch it without getting burned.

MX-3 Money · Post by **MX-3 Money** » September 15th, 2005, 8:25 pm

hgallegos915 wrote:I got a new throttle body and walla... no more high idle...it was running lean..manifold was getting really HOT you would burn yourself if you touh it..after the tb..i went for some hard driving and manifold was hot but not as hot as before I could touch it without getting burned.

What TB did you replace with?

hgallegos915 · Post by **hgallegos915** » September 15th, 2005, 8:34 pm

I had a klde tb and replaced it with another klde..(i have straight neck) also if you got straight neck you DONT want to have that spacer that the k8 had. It blocks the idle screw and makes it idle high. Also if you dont have a vacum to the fuel pressure regulator you will idle high, check accel cable also. Make sure your vsris points are not stuck open..mine was stuck open with the throttlecable. All fixed now.

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