I have owned a 2004 Mazda MPV LX since early 2006, and it has been a great vehicle so far. Plenty of room, fairly fuel-efficient, quite practical and very satisfactory on the whole… with one exception.
Starting around late 2007, the minivan started to occasionally stall while decelerating or braking. The RPMs would drop to near-zero and the engine would die. It only happened a couple of times over a few months but began to get more and more frequent as time passed. Generally it would only happen between 15 and 50 MPH, and only when letting off of the accelerator. After the first few times, I learned to avoid it by tapping the gas as I saw the RPMs plummet; if I did that in time, I was able to keep it from dying. If I didn’t however, my only recourse was to shift into Neutral, start the engine while rolling, shift back into Drive and keep going. Of course, this was quite unsafe, and by the time it was stalling once or twice every time I drove it, it was time to do something about it.
I did a bit of research online and found the occasional mention of a faulty IAC valve being the cause of stalling and rough idling. The folks at Kragen didn’t know what an IAC valve was, and I didn’t pursue it any further from there.
The van began to show a check engine light, so I took it in to the local Mazda dealership to have them check it out. It turns out the check engine light was the result of a sensor that was blocked by excessive carbon buildup in the intake manifold, which was caused in part by the stalling behavior. According to the tech, the stalling was causing the engine to run a richer fuel/air mix on restart (because it interpreted the stall as an indication of a fuel/air mixture that was too lean), and this frequently-richer burn was causing an undue amount of carbon buildup. They cleaned out the intake manifold with Seafoam (or a product like it), did a firmware upgrade, changed the plugs and wires (which I’d asked them to do as a maintenance step while they had it in there), and, $1,100 later, was given a clean bill of health. The MPV passed Oregon’s emissions testing, the stalling was gone and all seemed well.
A couple of months later, the stalling started to act up again, and grew in frequency as it did before. I did a bit more research and all available evidence still pointed at a faulty IAC valve. As it turns out, the folks at Kragen weren’t able to find the part I was referring to because it seems to go by several name/acronym combinations: IAC valve, idle air control valve, idle control valve.
Still not sure that a fix was in sight but willing to try it, I ordered a replacement IAC valve from an online parts retailer for around $65 and put it in. Replacement of the valve was very easy; it is attached to the intake manifold by two bolts, and has a simple wire harness attached to it. Here are two pictures showing its location on the engine. I saved these when I was doing my research and, unfortunately, can’t find the original source, but here they are:
Location of idle air control valve on MPV engine
Closeup of IAC valve
As you can see, the valve is fairly easy to locate. It should be in a similar location for the following years:
- 2002 Mazda MPV
- 2003 Mazda MPV
- 2005 Mazda MPV
- 2006 Mazda MPV
Years 2001 and earlier have the IAC valve attached to the firewall, but it should not be too difficult to find (the part itself looks the same as the one seen here).
Since installing the replacement valve around four months ago, the minivan has been running as good as it did when I bought it. There have been no issues whatsoever with stalling or rough running.
Pick up a replacement IAC valve from Amazon using the link below. The part is listed as being compatible with a series of Ford cars; however, the engines are the same and this will work for any 2001+ MPV.
Update: Slightly better image of the IAC valve below.
It's the gizmo with the red circle around it.
I have a 2003 MPV that has had the coils exchanged, not it is running hot while ideling, and the air conditioning gets warm, once I get some speed, it cools. Any help needed, not a lot of money to spend on repairs.
What if the van have a random misfire when on load? When go up a hill, it stalls and check engine came on. I took to my mechanic to do code scan each time the check engine lightcame on and each time he scaned a differend cylinder # is misfired. Yet it runs fine after afew stall and the engine light came on. Is this part of the iac or the coil? My mechanic recommend to change the booth of those misfired. All 6 sparks plug changed within 3 months. Any suggestion?
Random misfile on load is a coil issue. The second time I had a coil failure, it was two coils failing at once, so it could be that you have more than one failing. My approach was to simply replace them all.
Thanks to the OP – Awesome Post !!!
My car: 2006 MPV LX (v6)
Problem: Stalling at low idle, stopping.
Tried:
1) MAS Cleaner (nope) – tech said not to mess with the mass air sensor as it is fragile and expensive.
2) Battery swap test ( thought it might be weak battery) (nope).
3) Used throttle body cleaner to clean throttle body ( after removing air cleaner assembly) (nope).
4) Used throttle body cleaner (and q-tip swabs to clean out black carbon deposits in Ilde Air Control Valve) (worked!) No more stalling.
Using the cleaner alone didn’t seem to do it so I used q-tip swabs to clean off the depoits off the parts inside the two chambers of the IAR. Paying special attention to cleaning the steel pin running from the valve through both chambers. Alot of black gunk came off on the swabs when the chambers didn’t look that fouled up begin with. Do a thorough job here so you get as much black onto the swabs as possible being careful to not damage the rubber seal in the one chamber.
Worked brilliantly and super simple to do. Original IAR gasket was dry and reuseable.
Glad the cleaning worked as it took 15 minutes and saved me the cost of a new IAR ($69 at autozone). Note: other stores could not find it under “IAR” and the like but found the Duralast part referenced earlier in this thread.
Thanks a million for saving me some time and coin!!!
Thank you so much for this post. I was having the same stalling problems described by most and I wasn’t looking forward to long drawn out repair cycle with the local dealer for this intermittent problem that had been getting worse. The day before I found this post our MPV had stalled 3 times during an 8 mile city-driving run. I already had most (if not all) of the coils replaced over the last 18 month period, so I was glad to read that this could be something other than more coil problems.
I bought the suggested replacement valve from Autozone and installed it myself. It really is as easy as described. It has been about 5 days now since the repair and so far my 2004 MPV seems to running great with no stalls. It might be my imagination, but it seems to be running smoother with more pick-up than before the repair. My only concern with the Duralast part is that the gasket that came with the valve (which I did install) is not flush with the interior openings in the valve. The OEM gasket that removed had cut outs that exactly matched the shaped of the opening. Could this be a problem? Should I have re-used the old gasket?
Thanks again to all.
Dead on. I had the same issue and brought it to the dealership, they replaceed the PCV Hose and nothing changed, I told then about the IAC valve. They Checked it and Yup that was the issue.
Thanks for the help!!!
My ’01 MPV is having similar issues. The coil pack you guys are talking about, could that throw a code for a misfire?
Ross, I’m not 100% sure what the exact code is, but I’d definitely guess a misfire code would be the one.
Thanks for your post and I pray all of you, this is very use full discussion. I bought the mpv last week and start spending $$
my life become hell and now i stopped spending $$ and start review the answers. all are really good advices. thanks buddy.
i will try all my self step by step.
You sure seems to know a lot more about Mazda engines than I, had a new problem develop today wondering what you think: a few months ago the cel was coming on, I was going to get a scan and it turned itself off first so I didn’t. Not sure if that’s related, but today it started almost jerking/rough idle when stopped and the AC was on. This stopped when AC turned off. No other problems noticed yet. If my AC compressor is locking up, could this break my serpentine belt if it goes out? Thanks so much.
I don’t know enough about AC compressors to be able to give you a definitive answer on that one, but I’d keep watching it for a few more days (try the AC occasionally) and see if you notice the jerking and rough idle when the AC is off. If it’s the coils (like mine), it won’t start happening until the engine has warmed up for a while. I’m guessing that the added load from the compressor, as it puts more load on the engine, could be causing the coil misses, but I don’t know for sure if that would be the case. Either way, if it is the compressor going bad, you should notice a difference in idle nearly immediately between switching the AC on or off.
Thanks, it has started happening now without the AC on as well, probably a coil causing a misfire or something like that. Sigh, eventually I’ll find the time to get that fixed.
Such great information! I found it while searching for a solution to another issue we are having with our 2002 MPV. I’ve had 2 coils replaced so far and know that there are more in my future. But thanks for the info on buying them yourself, should save a few dollars. So I thought I’d ask since you seem to know these vans inside and out… anyone have an issue with the van not recognizing that it is in “park” and won’t let you turn the vehicle off and take the key out? This happened to me last night, luckily (I think) the dealership’s service was open and I drove it over to them. They disconnected the battery so it didn’t sit in “ACC” and wear it down, but they are telling me it is a “change control” to the tune of over $500. Wondering if there is a simple fix – like something just came disconnected in the steering column. Any thoughts would be appreciated. Thanks again for the info!
Gretchen, from the sound of things, the “change control” they are referring to is simply another term for the transmission selector switch or gear selector switch. Here is a tech writeup that discusses how to remove the selector switch and diagnose the sensors, but it’s a bit technical and involved (be really careful with the airbag, if you do this): http://www.mpvclub.com/diy.php?id=116
From reading on forums, I’ve also found that you might be able to get the key out if you pull the Hazard fuse temporarily, but be sure to put it back in since your turn signals won’t work without it.
hey,
my issue is kinda’ the same but a bit different. maybe someone could offer some advice. weve had our 2005 MPV for a bit over a year. occasionally while the A/C is on and the car is idle at a light, the RPM will suddenly decrease to a near stall (on 2 occasions the car has actually stalled but usually it recovers before it stalls). until now we have come to live with this issue, but recently the car started hesitating and jumping when i pushed on the gas either from a complete stop or while driving and needing more power from the engine. i took it to the mazda dealer and they changed a coil and the car ran great for a couple of days and then the same problem occurred again, only this time, in addition, the cars idle was totally out of whack even while just moving along in bumper to bumper traffic without hitting the gas pedal. they told me it was now another coil and changed that one as well. the car seems to not be having these hesitating/ jumping issues anymore when i hit the gas pedal, but the near stalling/ stalling issues while the A/C is on and the car is stopped at a light is still happening. im not sure if the 2 issues are related or not. could this also be an IAC Valve problem? can anyone from this brilliant group suggest anything to stop the sudden loss of power while the A/C is on.
I have a 2002 Mazda MPV and thought the IAC might be my problem as well but no luck here. Replaced it and still having the same problem. I have to hold the gas down to get it to start and when it does it revs high like I’m giving it gas and as soon as you try to put it in gear, it dies. The transmission is also switching gears hard and the motor is running hot but not showing on the gauge. Anyone got any ideas on this one before I spend an arm and a leg to fix it?
So I just found online a Mazda service bulletin referring exactly to the problem I am having with my MPV which is “ENGINE IDLE DIP WHEN A/C CYCLES ON” . The only problem is that it is for 2006/7 mazda 3. does anyone know if this can be used for the MPV’s as well, and if not where I can find this same info for the MPV?
My 2003 Tribute was running rough and stalling off and on for 2 years. Replaced IAC and cleaned MAF. One day i popped the hood and there it was. The PCV hose going into the intake manifold had a gaping hole in it. I never saw it until then.
I wrapped it in Duct Tape and no more problems. I replaced the hose 2 days later. I got the part from the dealer for $10. I had a repair shop wanting to charge me $400 for a tune up they guaranteed was causing the problem.
Thank you for everyone post about Idle Air Control (IAC) Valve.
My 2000 Mazda MPV start having problem with cold start up and can’t keep up the RPM at all. Keep turn off the engine everytime I cold start. After I do a reseach and reading all about you guy posting IAC valve. So I decide to order Idle Air Control (IAC) Valve three day later received the part arrive to my home. I install IAC now everything back to normal running engine RPM hold 7000 ok.
Again thank you everyone for your help.
Kenny
Wow, that was painless!! Thank you for the step-by-step rear coil change! Besides dropping the gasket down into the engine (hour and a half to find) it was quick and easy. Now, the engine doesn’t jerk and constantly hesitate, but it still has a minor rough idle and hesitates starting from a stop. I replaced the IAC and still no change. I only changed the rear coils figuring the coils weren’t an issue anymore since there isnt any jerking anymore. Any thoughts?
I have a problem that is about the same but different. I can start my van and leave it parked all day long and rev it up with no problem. After I start driving it about two blocks later it starts to jerk and stalls. The codes were lean on bank one and two, random misfires. The diagnostic tool showed the fuel trims to be adding in 15-25% more fuel than was needed. I replaced the IAC and the engine coolant sensor. I put in new spark plugs. I haven’t replaced the coils because I had them tested and they were good. I may just buy new ones anyways to be sure. So after it stalls I can’t start it for at least 15-20 minutes. I pulled the spark plugs out to see fuel on them so I know the cylinders are getting flooded. Any ideas?
i have having the same problem with my mazda premacy sport,had a boy look at it today and he reckons its the idle control valve.not stalling,though running rough now and again so i am going to get that changed over asap,now that ive saw proof thats its causing same issues to others…………cheers
My 2003 Mazda MPV started stalling at stop signs the first few times. But it was on a trip in the middle of Kansas – had the cruise on traveling around 60mph on a rural highway when the automobile just stalled – that I started to get concerned. It was odd, I pulled over, started it up and made it the rest of the way home. Two days later, it stalled twice on a seven mile trip on city streets. It was then that concern grew to dread of the service bill that was going to be coming as a result of this problem. So I got online to find out what might be happening and how much it was going to set me back.
I found this website after reading many accounts of high cost service that seemed less than fruitful. I decided that before I took the car in for service, I would try this solution out. I spent more time waiting to be served at the parts store than I did installing the part (I am NOT a mechanic at ALL) and $61 and a month later, the van still runs like a charm. I want to thank you for your pain in finding the solution and the kindness you shared through your work of putting this out in cyberspace. Amazing!
I’ve had a check engine light reappear a while after all the plugs and 2 of the coils were replaced. The other symptom is a rough low idle in gear and in park. It runs fine at speed. I put in a new IAC valve after seeing this website hoping to finally fix it. The check engine light went out, but the idle was at 3000+ rpm instead of a 1000+ rpm. Driving it was scary! It was hard to stop and it ran crappy at speed, jerking and dipping acceleration. Any thoughts?
I can’t thank you enough for posting this information. My 2002 MPV with 53,000 miles was began having trouble starting in cold weather two years ago. I went through numerous batteries thinking that was the problem. Then this winter (after another new battery) it would start, but as soon as I put my foot on the brake to put it in a gear, the engine would stall. I saw this web site and mentioned the IAC Valve to Mazda. They replaced it saving me a lot of time and money. My MPV is running great and is now starting in cold weather without any problems. Without your help I have no idea how much it would have cost me for Mazda to diagnose the problem. Thanks again.
Had a 2000 MPV with an IAC that kept getting stuck and made for some jolts when backing up our driveway. Cleaned it out several times. Always seemed to be fine once running.
Just got a 2006 MPV and it started stalling randomly under 40 miles per hour. Didn’t make the connection until I came across this post that it was the same thing. Replaced it with a new one and haven’t had a single problem since. Thanks so much!
Thanks, many thanks for this post.
I had the same problem and replaced it before yesterday, no problem again.
The dealer told me no any problem, just clean the history code and spent me 120 bucks, and everyday get this problem in last 1 month after the dealer did.
Found this article based on the perfect description of the problem: engine stalls when removing foot from gas pedal at high RPMs.
Affected model was a Mazda MPV 2006.
The link to the part on Amazon looks like a perfect match, but I ended up at the local NAPA store where CRB 216623 (“Idle Air Control Valve”) gets you a similar looking part, albeit more expensive than at Amazon.
If you look it up online (to check in-store availability), you’ll notice the NAPA site complains the part isn’t Mazda MPV compatible, just like Amazon does. I wasn’t worried about that, based based on Jacob’s heads up. Given the choices offered on both sites, it looks like they use the same (incomplete) part compatibility database
Replacing the valve fixed the problem. Thank you VERY much for posting this suggestion!
I was having the same problem. I ordered sparkplugs as an error code came back telling me that it was misfiring. Installed them, but didnt fix rough idle, stalling issue. Took IAC \off cleaned it reinstalled it..still rough idle…thought I will order new IAC.
I also was going to replace master cylinder..as it stopped working as well….anyhow…before you order IAC…check for a vacum leak, this was my whole prob. Behind block there`was a quarter size hole in what I belive to be the pvc hose…plugged it with a larger nut and tape..and whalla….idle was better than ever, and brakes worked! Not need to order the 90 connection!
check for vacuum leak first! Listen first.
Mike
to follow up\ on above comment read the quote below
“On some 2002-2003 MPV vehicles, the Positive Crankcase Ventilation (PCV) hose may fail, causing rough idling and/or the Malfunction Indicator Lamp (MIL) to illuminate. If this failure occurs, the vehicle may not pass applicable emissions standards. Mazda has decided to conduct an Emission Recall Campaign to replace the PCV hose with a modified hose.”
Could the IAC valve be the problem if the engine stalls on acceleration? I have a 2004 MPV and just changed the coils due to a misfire on cylinder 3. Everything seemed fine but a day or two later it died when passing someone on the interstate.
I have a 2000 MPV when I start it in the mornings it revs up and down on its own. Could this be a IAC problem? Also it makes a horn like sound at random times while driving or idling. Thanks in advance for any suggestions
The repair worked like a charm for me as well. Thank you so much. I had the coil issues first and then got the stalling. Fixed the coils, still had the stalling. Replaced the valve and has been running perfect for two months now.
Same problem happened to my 2004 MPV. Dealer couldn’t find code and suggested changing snorkel for $250(??) Purchased the IAC valve online, got a mechanic to replace it and van is running smooth again. Glad I found this site
I have a 2007 Mazda MPV with the same stalling issue while driving. Its so dangerous. Any opinions out there whether replacing the IAC valve will help my problem as well?
Thank you
Any suggestions for idle surges on an 2002 MPV? Van startskmok and runs great, but willsurge when idleing
My 2005 MPV LX stalls at random while driving. It seems to occur when the gas pedal is released between 20 – 50 mph. I just ordered a new IAC valve. Thank you for putting this info on the web! You probably saved me a ton of money and time.
Replacing the IAC is likely to help – it did on my 2006. We had the car stall x 3 and then brought it to a mechanic here in Italy. They were confused, so I called a dealership in New York, who was happy to help. The recommended this replacement and it worked like a charm. The process was very easy. Everything was fine for 5-6 months, but now I have another problem.
When I start the MPV, it idles in the 1500 range, and putting it into gear feels like riding a horse which is anxious to get out of the gate. If I wait 30 seconds, then rev the engine, it will drop to 800 RPM and drive without problem until I start the car again. I’m not sure why this happens and am guessing it isn’t a hose leak, as it only is an issue on startup. Could it be a sensor?
My 2004 MPV is hit or miss with how the engine runs. I’m driving along and it feels like is sputters, or hesitating as I accelerate along the highway. Happend in May after a 1 hr drive & then again in July after a 2 hr ride. The AC is on and then I won’t happen for week. Is this the IAC issue that I can get at AutoZone. My Firestone mechanic said it was a Mazda recall on PCM part & I would have to have Mazda take a look. What a pain…help?
watch for the vacuum leak especially on the pcv line on the aft side of motor, mine kept faulting o2 sensor, showing lean condition in 3/4 bank turned out to be the vacuum leak was leaning out the cylinders, I did not find this out till after I changed the O2 sensors and it still faulted a lean condition, so I changed the pcv line and all was good. great site the IAC valve is a common problem on fords (had this on My f150) and the MPV v6 engine is nothing but a Ford(parent company to mazda) taurus duratec engine .
I am having a problem with my 2004 mazda mpv. The engine surges when stopped at a redlight. The vehicle would jump forward if the brake is not held down. This is different than the coil problem (already experienced that one). I have replaced the IAC valve (which the old one wasn’t that dirty) but this did not fix the problem. I was wondering if it could be a sensor or hose issue and if so where would I look?
Ron, it sounds like it could be a bad PCV hose. There was a recall for 2002-2003s but it affected mine as well and I had to replace it. Here’s the recall notice: http://mpvclub.com/recalls.php?id=17
Here’s a new PCV hose on ThePartsBin.com for $17.95+s/h. The hose is listed as a 2002-2003 but should work fine for your ’04.
THANK YOU for this post. Saved us a BUNCH of money and likely helped my wife avoid a serious accident with our MPV. Took our car back to the mechanic for help on the stalling. They were open to looking at this thread but weren’t sure that it would solve the problem. I asked them to replace the IAC since it was worth the risk and this car (our main family car) was nearly undriveable. Cost me about $100 to have it installed. The car hasn’t stalled since. A great example of how the web can do some great stuff. Thanks again.