NOOOOOOOO (@&%ing Idle!!!!!!

[sapper]

Is it just me or is this problem limited to just manual transmition cars? Does anyone running an automatic have this probel?

[atlantamx3]

Oh Man.<p> The problem is even WORSE in automatics!! The only thing we can do is put it in Neutral or two-foot it @ the redlights. (press the brake and gas @ the same time.)<p>Autos Suck. I know-- I have one. A SOHC. <p>SOHC's SUCK

[wOOge]

hey all..
over the past year i've had the same issues in my '93 4cyl. SOHC... recently it's become rediculus.. stalling at nearly every stop/gearless slowdown.<p>(nothin like having to jump start your 'cidia doing 160 on the HW...)<p>so i took my beast into the shop and aparently i'm loosing compression in all four of my cyl. tests showed there is a difference of anywhere between 40 and 75 lbs per cyl.<p>i'm hopefull that a larger air intake, and some of the remedies mentioned above will help me out... like resetting the ECU / cleaning the IAC (what is this btw?) and adjusting the idle speed.

[Marlon]

i fixed the problem
i swaped in a bp and no more problem

[992mmx3]

bllaaahahaha. I'm still wondering why it happened to me, I would turn on my defroster and hit my brakes and it would idle low, someone figure this out!!

[2fazed]

I had that problem for the pasted 2 years. Took it in last November, been fine since. Doesn't cut out on turns or stops. I went to a Mazda specialist, not the dealership, they said don't mess with the idle screw, it has to be set with something, that I would need a device they had. And they did something regarding my power steering, I'm not sure what, buy they said it is comand fix to all Mazda's, anyway it all worked, and I'm relieved not to have to worry about stalling all the time.

[boostedmx]

few things to check:
throttle cable adjustment
idle speed adjustment
distributor timing, move it around, see what works
coolant level-(major effect on idling)
intake manifold leaks
dashpot sticking<p>and as a preventative measure, decarbon everything, use carb clean and clean out all valves, solenoids , passages, throttle body. also do a block test and a compression test. with all these tests done you WILL find the problem.

[guyaverage]

I dont want to go bashing anyone here, because a lot of you have done a lot more on your Mx's than I have on mine, but I personally would find it interesting to take an informal poll among the people having this idle problem, what percentage of them have taken the time to remove the IAC valve, cleaned it THOROUGHLY, put it back, jumped the #10 pin to ground, reset the idle, then reset the ECU, and find out how many of them still have the problem. I'd bet most havent, or dont even know to do this. Granted just because it was the problem in my car doesnt mean its the problem in everyone elses, but since so many people have this problem, and if you look back in the archives a lot of people report having been told by Mazda this is the problem, I'd bet for the majority of us this IS the problem. <p>throttle cable adjustment- Unless its pulling the throttle closed, I cant see this being the issue.. but I agree, you've got to start somewhere<p>idle speed adjustment- I agree, if this is out of whack the problem gets a billion times worse<p>distributor timing, move it around, see what works- this will definetly effect idle, but I wouldnt go moving it around without marking where it was, unless you have a timing light to put it back where its supposed to be, or where it was to begin with<p>coolant level-(major effect on idling)- Major effect? Whats the mechanism behind that? If the answer is in its telling the ECU the engine temperature and effecting the idle mixture, I would go along with that to a point.. but if the coolant level is so low to cause that problem, I would think at the least you'd notice a very hot indication on the gauge. When I had my water pump leaking problem last month it took almost 3 quarts to bring it up to full, and the gauge was barely above normal sitting in a big traffic jam, and it didnt do anything to my idle.<p>intake manifold leaks- This will definetly effect idle also, but so many people having manifold leaks? I wouldnt think that is likely, and would it would probably cause noticeable driveability problems too (maybe, maybe not)<p>dashpot sticking- Does this car even have a dashpot? If you say yes I believe you, I have had to pop the hood on this car so infrequently in 10 years I dont even remember seeing one. Even so, this would only effect when you let off the gas, not sitting still at a stoplight or just sitting idling in a drive-thru or wherever. Dashpots keep the throttle from slamming shut when you let off the gas, once your foot is off the gas and the throttle is back home, the dashpot is out of the picture, unless you sit at stoplights or in traffic blipping your throttle the whole time like the geeks I always seem to get next to....<p>Still, it wouldnt hurt to check EVERYTHING anyway. One thing for sure, a LOT of people still have the idle problem, and I cant believe Mazda doesnt have some formal TSB out about this. I'm just happy as hell the IAC was the problem on my Mx. This will about drive you nuts.

[maldo]

Couple things Jarid, definitely clean the IAC/BAC system while the car is running using a good carb cleaner. These valves like to get stuck, mine was stuck wide open causing an extremely high idle at one point. Check the electrical connection, (did you swap to the B6T components, I don't think so but anyway), on the B6T the connection is reverse so that could be causing part of the problem. Double check all your i/c pipes for leaks, an easy test is to use duct tape (fixes everything) around each weld. Check the BOV for leaks, is it recirculating? if not try recirculating it to see if that helps. You have larger than stock injectors, correct? What ecu and what form of fuel controller are you using? Fueling could be causing a poor idle if you are just using the stock ecu.<p>Let us know the results

[Guest]

ok i dont know all the technical terms but i had this problem, from what i remember it was my idle control valve, something to do with engine temp and idle, which makes sense because the car had to heatup before it started the up and downs. <p>Not sure the proper name for it, anyways if you unplug it the prob will go away and then you'll know if thats it. Because when i bought my car that valve wasnt working but the bastards that sold me the car had unplugged it so every thing seemed fine.

[guyaverage]

Thats exactly what mine was doing, it was fine when the engine was cold, when the engine was hot is when I would get the stumbling idle and the almost-stall when coming to a stop. It was only when the engine was hot. What the person who had you car did was probably unplug the IAC valve. In reading other posts on the forum thats what some people have done to make the problem 'go away' but that is not a fix. Thats like having a brain tumor and "curing" it by taking aspirin to make the pain stop. You still have a brain tumor. Unplugging it may make the idle steady in most situations, but it isnt solving the problem, especially if you have an automatic. And dont unplug it and think you wont have a problem when you turn your air conditioning on, the car will barely run. Since REMOVING the IAC valve and giving it a THOROUGH cleaning is cheap and quick, its the best place to start. (I'm not a big fan of trying to clean anything like this while the engine is running. The relative pressure inside the intake tract will evaporate a lot of the solvent before it even has a chance to disolve any of the carbon and gunk.) If that, along with readjusting the idle speed and resetting the ECU (in that order) doesnt solve the problem on your own Mx, then go from there. But its a waste to hear about guys just spending all sorts of money buying plugs, wires, dist. caps, gaskets, sensors, etc etc working the "shotgun" method of replacing various parts in hopes of stumbling onto the cure while trying to fix the problem, at the same time overlooking the very device whose specific job is to maintain the idle in the first place. The IAC is not the problem on everyone's Mx, but I would personally place my bet thats what the culprit is in 90% of the cases.

[boostedmx]

they sell a top engine cleaner that hooks into a vacuum line and feeds a cleaner through the intake system while the car is running. we have had major success with this product. it cleans as well as lubricates at the same time. any parts store should carry it.

[maldo]

Jaime is right, it is better to use the cleaner with the car running as the vaccum of the engine pulls the cleaner thru the clogged systems.

[guyaverage]

Are we still talking about cleaning the IAC valve? If you're plugging into a vacuum line, you are already behind the IAC valve, which means the solvent is not going thru it. There are two vacuum lines on the passenger side of the engine, and one on top of the manifold behind the throttle body. Plugging into either of these is not going to get cleaner into the IAC valve. If you say you are having good luck with it, then by all means use it and have fun. I have seen these plug-in cleaners before and I have yet to see one doing a good job of cleaning anything upstream of where it is plugged into.