2nd Oct 2002, 14:28

My 1997 626 2.0 had the rough idle it turned out to be the idle air control valve. After pricing it at over $400 I said no. I found out that you could remove the solenoid from the top remove the spring and clean all of the carbon out of it. It solved the rough idle concern. Hope this helps.

9th Jan 2003, 19:06

Mazda 1994 2.0 L.

My 94 mazda 626 was stalling out when the clutch was pushed in and going down past low idle when it was hot and based on the comments I saw here, determined it must have something to do with the idle control valve. I took it apart to clean it and saw that the spring under the solenoid was completely out of position. I reassembled it properly and voila! it didn't cost me a cent and idles perfectly again.

Thanks guys for the hints.

19th Feb 2003, 19:10

I am having the same problem with my car. I wanted to know if anyone has any pictures showing how to clean the idle air control valve. I do not want to break any thing on my car and am not sure how to take it apart. Any information on this will be helpful. Please e-mail me at billy_21915@mybluelight.com.

18th Jun 2003, 07:01

I also have this idle air control valve problem with my 1995 Mazda 626 2.0L. I took the solenoid off, and out dropped 3 parts: a large spring, a small spring, and a red plastic tube with one end recessed. So, I cleaned everything, and guessed how to put it back together. Now, the engine idles at about 2000 RPM. Obviously way too high. Anyone know the correct order these 3 parts go in when reassembling the valve? Obviously the springs go on each side of the red plastic tube, but which goes down in the IAC and which goes up in the solenoid?

24th Jul 2003, 10:43

I have the same problem with my 99 Mazda 626 (automatic). At stop light the car idle between 500-800 and sometimes start stalling before the ECU catch up. Someone told me it's a problem with the Fuel pump, but I have that checked out and it looks fine. Any suggestions will be greatly appreciated. E-mail: agomes_umd@yahoo.com.

29th Jul 2003, 11:35

I too have had the same problems with my car and the Idle Air Control Valve. However, what began as rough idling at stop lights has now progressed to my car "sputtering/jumping" at highway speeds! This only began after I cleaned the IAC valve. Anyone have the same problem or have any suggestions?

26th Aug 2003, 14:38

I have a similar problem with my 94 626. After I replaced teh battery, the car started idling very low and stalling. It has even stalled when while coasting (to stop or slowing down).

29th Oct 2004, 04:28


I had the same problem when my mechanic changed the time belt, it so happened that the mechanic had connected the wrong wire which was causing that. I don't know the name of the wire I will find and let you know.

27th Sep 2007, 12:25

I have the same problem with my 94 mazda.

27th Jan 2008, 22:57

I had the same idling problem with my 1998 Mazda 626 LX. After cleaning the idle air control valve and the mass air flow, nothing changed. I finally brought it to the Mazda dealership and had them run the computer to it for $80.00. Turns out, it was a bad intake gasket. I bought the part for $20.00 and it is about 3 hour job for any mechanic to replace it. When it was replaced, the car runs perfect!

8th Jun 2009, 16:04

I have the exact & same idle problem on my 1998 Mazda 626 LX (Automatic, 2.0 liter, 4 cylinder).

The problem started after I had my timing belt changed at about 98,000 miles. I was told by the mechanic that the engine was "fine tuned" by him and I noticed the idling is bit high (above 1000 RPM) at parking.

Car will randomly idle low at stop lights, car almost stalls, then engine surges back up to normal idle speed. Happens every few seconds at stoplights and even while taking turns (where RPM comes down to about 500). Whole car body vibrates during this behavior.

I took it to mechanic and he replaced spark plugs, cable set. but still no difference..

No idea what the problem is - mechanic failed to fix it after taking it back twice (spent $480 totally).

Please send me if anybody had any luck in fixing this problem: cru090@gmail.com

9th Jun 2009, 03:51

I have a 1998 Mazda 626 4 cyl. I have cleaned the IACV. I know that if you take a little square 9 volt battery and touch both ends with wires to the leads on the IACV valve, it should click open and then shut when you remove the electricity. I wonder if the idle problem is from the ECU not sending electricity to the IACV to keep it open, therefore it remains shut causing the low idle and fluctuating idle especially in gear. The IACV unit is a magnetic solenoid; it only pops open or closed, no where in between. Does anyone know how to tell if the the circuit between the ECU and the IACV is getting electricity? Please let me know. thanks.

22nd Jun 2009, 06:22

1998 Mazda 626 2.0 4 cyl .I found that the IACV was not getting electricity, although the wire was hot with 12 volts. I had to cut the wire and put electrical ends on the wires, then attach them to the IACV. The valve was not opening to let air in. The computer could not adjust for that. It idles quite a bit better, although I have not figured out the highness of the idle in park.

3rd Jul 2009, 23:01

1998 Mazda 626 rough idle. Erratic idle. Have found that the the valve opens with the control of the ECU, but does not stay open - only a few seconds, then closes. I suspect the valve should stay open because the voltmeter says the wires are still hot. Will seek to replace the IACV valve. YOU can get them for just under $200 new.

9th Nov 2009, 14:10

OK, wow, I just came across this site and I'm glad I did... I own a 1998 Mazda 626 LX 2.0 4cyl and have the SAME idle issues... last year took it in and paid $400 to have the intake manifold gasket replaced!!! That solved the problem; until now that is...

I just had the timing belt replaced and water pump, and now the car is doing same idling problem. When I come to a stop, it drops way too low, and shakes and almost chokes out. Sometimes it stalls, sometimes it won't, but trying to sit at a stop light with your foot on the brake while the other revs the gas is just not a fun way to drive LOL.

Am bummed to see so many others having this same idle issue. Makes me wanna email you all and lets all get a hold of the Mazda car dealerships and see what can be done to correct this once and for all!!! LOL :)

Otherwise my car runs terrific and I love it! Can't I just turn up the dang idle? LOL Where's that switch... where's my Haynes manual at LOL :)

Any other suggestions, let me know anyone please LOL runaelovesgreen@yahoo.com

Runae from colorado.