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Hey all! Just bought my mx3 a week ago. Its a 94 blaze red 1.6 DOHC with a 158,000k. I seem to have an idling problem, it idles really low sometimes (bouncing between 200 and 600 rpm) and sometimes dies completly. It seems to be running fine while driving in gear. Did anybody experience anything like this on their car? Is there a common problem to this? I appreciate any help or suggestions. THANKS A LOT!!!

Seems that alot of ppl here have had this problem. The most common things that cause those problems are, Throttle Position Sensor or TPS, Poor Grounding Points, Dirty or clogged Idle Air Control Valve, And the Most Common is the Alternator which has always been an issue affecting the 1.6 L. It helped me alot when I bought a new high output battery and high conductivity bettery terminals, Also cleaned the Ground Points. Stock alt. output on the 1.6 L is only 65 AMP's so upgrading to the V-6's alt will drastically improve your idle as it runs 90 AMP's. Other things to consider would be spark plugs, Spark plug wires, Cap+Rotor and check timing. Hope this can help you!

a couple thing to try are

first clean out the throttle body (that could be the main issuse) after that has been cleaned out adjust your idle speed on the throttle body

next go to walmart / canadian tire / or any autoparts store
and pick up two bottles of fuel injector cleaners or if you can find it around you Red Line fuel system cleaner (this sh*ts great) if you can't find the red line get the 2 fuel cleaners and add them to your tank with only about a third of a tank left drive then drive for about 15-20 mins then fill the tank this way you'll force the cleaner to work faster (don't worry it won't damage anything)that should help with your fuel delivery and after you adjust your idle you shouldn't have any more idleing problems.


now by upgrading your ground points you'll help your electrical system and in turn help your idle (upgrading to the gs alt is not requried it will help but there are other thing that are easier to do that help just aswell only as i last resort would i suggest going with the bigger alt)



but you must adjust your idle on your throttle body to have anything work



Reaper
Greg

omg someone sticky this or something...someone makes a new post about this same problem about once a week with the same solutions and nobody uses the search function apparently...

Dont forget to check for vaccum leaks first .....

If other proposed solutions do not work, it could be your Engine Coolant Temperature (ECT) Sensor. FYI - If I recall correctly, it is on page F-162 of the manual... The ECT is located by your distributor.

I'm raising this as a defective ECT can lead to intermittent low idle issues (almost to the point of stalling). This is particularly the case once the car warms up.

Good luck!

The MX-3 is now known for the notorious idle problem lmao.

OK, I have changed the plugs (the wires were changed by the previous owner) used fuel injecter cleaner and cleaned the air intake manifold.... Yet the problem hasnt been solved. It still idles like crap dropping to 200 rpm...I am getting frustraded by this problem...Oh well, I guess I'll have to change some of the mentioned sensors. Thanks guys.

I guess I should mention that the check engine light comes on also...I would love to replace everything suggested on this forum but I am on a budget. So what should I do??? Alternator? TPS? Idle air control valve? Please help.

94blaze1.6 wrote:I guess I should mention that the check engine light comes on also

Pull codes .... that will tell you whats wrong ... almost ....

it's good you cleaned everything pull the codes , untill you get it fixed adjust your idle for the time being to at least be able to run the engine


but sounds like you might need o2 sensor that would be the first one i'd check.

reaper

Codes do and don't help you. All codes are is basically if a sensor is bad or the sensor is reading some crazy shiz

I have a feeling it is a sensor, havent had a cahnce to pull the codes yet but I will keep you posted. Thanks guys

Hey guys - been reading this post to find out how to fix idle on girlfriends 93 4 cyl mx3- how do you adjust the idle on the throttle body? I can't seem to find an idle adjust screw. Also - how do you clean throttle body? I pulled off intake boot and sprayed a bunch of carb cleaner in (it was a bit dirty, but not gummed up). Lastly, is there an idle sensor to clean? Wheres that? I've been skimming the posts and find what to do, but not how to do it.

Thx

I have searched the online manual on how to adjust the idle, but the change I made did not take. Can someone post the correct sequence for making the change.
1. Engine on /off?
2. Run the jumper wire?
3. Adjust the idle speed?
4. Pull the jumper?
5. Stop engine?