I have been experiencing a rough idle for several months on my on my 2002 LX Tribute. The last time this happened (last year) I cleaned, then finally replaced the IAC valve, which worked great. Now it seems to also be more of a driveability issue- the vehicle stalls/misfires in park, neutral, and in gear with foot on brake and during low gear acceleration.

After taking it to the Mazda Dealer,they said that I need to replace the #1 and #6 ignition coils . The idle and misfiring problem I have feels very similar to when I replaced the IAC valve, which was easy and painless. The check engine light never came on either time, which surprised me. When these symptoms occur, is there a good way to rule out the IAC vs the Manifold Gaskets vs Electronic Sensors vs Ignition Coils/Spark Plugs/Wires? It seems like these tend to be the most likely culprits.

The Mazda dealer suggested that I let them replace those 2 ignition coils (I assume there is one IC for each cylinder?) plus all 6 of the spark plugs and wires. I have 85k+ miles and bought it used at a little over 60k, so it's quite possible the plugs/wires are original.

I was quoted $575, which they reduced to $520 for parts and labor with this job. That seems pretty high to me... or am I being unrealistic? Does anyone think I should attempt it myself? I am a novice but fairly technical. I am not sure about the disassembly required for 3 of the the plugs, and I have limited tools... so I am leaning against that option.

If I decide not to try this myself, is it something any decent non-dealership mechanic worth their weight in salt could do to prevent me from sinking a half grand into it (and maybe still have the problem)? I live in the Detroit area, so I figure there are plenty of mechanics to be found in a tough economy that would be happy for the work at a more competitive price.

 

i had the 3 rear ignition coils replaced (85$ each) when they had to take off the whole manifold and all to get to the sparkplugs.figured do the coils while its apart.figure 3 hrs labor at 90 =270,plus your 2 coils =170$.plus theres six gaskets when they put it
back together, so your cost seems right on.your at $440 plus gaskets and plugs.
you can always and easily do any of the front 3 coils and plugs.it 's those 3 rear that involves the work.if they are doing ONE coil in the back, do all 3.hey,whats an IAC?

 

So I had a similar problem with my 01 tribute. I have replaced the coil 3 times in the last month and replaced spark plugs. My next step is the wires

 

IAC is idle air control; it's part of the engine control loop which serves to keep the idle speed optimum for the engine, takes into account battery state of charge, eng. temperature, A/C on- off, and accessories load.
Before spending big bucks on an "engine reno" project, here are some things worth trying and don't involve much more than a bit of TLC on your part:

Normal no load engine idle is 700 - 800 rpm. and is pretty solid; even when the A/C compressor cuts in out the surge is minimal and of short duration.

Try first of all making sure that your mechanical throttle linkage is clean and in good working order and the cable linkage, cruise control link and the return spring mounting is secure, and the throttle plate movement is smooth and free.
Next (although this is specific to the 1.8L ZM or FP engine, it's generically applicable to all 1995- 2000 4 cyl. Mazda engines, and is generic to the extent that even 6 bangers benefit from this kind of first aid).

Before getting into serious money, I suggest you look very carefully at that ducting between the air filter unit and the engine intake. Unclip the air filter, and don't be hesitant about really moving it around a bit either. The air duct has a habit of getting brittle and splitting apart. What happens is it seals at rest, the engine is then torqued on the mounts as you engage gears, then the movement of the engine opens the split, letting air (which the MAF doesn't "see") into the engine, making the mixture way too lean. Now the engine complains, rocking to and fro on its mounts, making the ducting work like an accordion (with a split bellows), so the whole show just rocks (literally) on the engine mounts. This you can fix with duct tape.
If the duct is OK, then next you get yourself a 2ft. piece of tubing (even garden hose works), and use it like a stethoscope to "earball" your way around all of the plumbing which is connected eventually to either the throttle body or the intake manifold, listening for sneak leaks. (The underside of the hood has a "map" of the vacuum circuits.)

Another common weirdo of Mazdas is that bad ignition hickups can throw the ECU for a loop. Get yourself a spray can of contact cleaner (which is good for cleaning the MAF anyway), and remove the two connectors at the front of the coil packs. Give those connectors a really good cleaning with the spray, and clean the dirt off the coil packs while you wait for the contact cleaner to do its job.
While you're at it , disconnect the two connectors on the air filter/MAF assembly, (MAF and Air Temp.) and squirt them too. Then take the tube off the spray can and shoot a good shot down into the MAF itself too.
Now go back to the coils, spray them with WD40 and clean them up well, using an old toothbrush, rag or whatever.
Next, check the condition of your plug harness. If it's old, it will arc onto any metal it gets close to, so make sure all of the wires are 1/4" or so clear of metal and each other, and that the plastic spacers which slide onto the mounting tabs on the engine head, are clean and in good shape too.
Now put the four connectors back where they belong, but connect and disconnect them a few times to ensure good contact.
Start your engine, warm it up, note the idle speed ( should be 700 rpm. and stable to +/- 50 or so) , go for a run and (if you've got it) check out your cruise control.
Now call it end of phase one, and post your data and findings on this thread.

Something I forgot: for automatic transmissions, a sick engine can put the car into limp mode which can block the transmission at 3rd. Left too long this will hammer the transmission and result in fluid deterioration or worse.

 

A couple months ago I started having problems with my 01 tribute dx that has the V6 3.0 duratech engine. It started running real rough, but only on occasion. It seemed to do it mainly at start ups or after being driven around stop and go stop and go. It sorta jerked and vibrated the entire vehicle and the idle was terrible. It was also totally gutless and the rpms ran real high. Well the check engine light had come on (Ignition coil A. Primary circut malfunction.) Okay so I replaced the coil and she ran well for about 3 weeks. Then it stared again and my check engine light came on with the same code. So I replaced the coil again, along with the spark plug. Well 3 days later the problem returned and the check engine light came on once again.
This time I decided to swap out my coils so I switched them out and during the test drive my check engine light returned and it showed the same code. So now I knew that the problem wasn't my coil it was something else. So I replaced the pigtail socket thinking maybe my connection wasn't that great.
But after replacing that the problem remained, my check engine light returned. And this time I got the same code as before (Ignition coil A. Primary circut malfunction.) but I also got a misfire on cylinder #3.
So now I'm upset I changed all my spark plugs, replaced coil packs in #1 and #3 cylinder, I replaced cylinder #1's pigtail socket and cleaned the others while I made sure the connections were good. I have had a compression test. Which was normal. Checked all my fuel injectors. Which were fine. And the car still runs rough and gutless. What else can I do?

 

If your ignition electrics are behaving like that, and your vehicle has horrible idle and lacks power, its time to check the engine timing sensor and timing belt. Any vehicle with 100K plus miles on it, has never had the belt changed, and behaves like that while throwing a misfire CEL should have had the timing checked absolutely before anything else, because that would have killed two birds with one stone, and avoided unnecessary expense on your part.
If that's what it turns out to be, get it fixed and find a new mechanic, because you've spent a lot of ignition system dollars for nothing.

 

You can order parts form an on-line store and save a ton of money on parts anyway I refuse to pay shop rate it absolutely insane. So to get back to it it's really not that difficult of a task and if you put your big boy pants on I'm Shure you can handle it. You need torque specs for pelnum and the plugs as well as the sequence. There really isn't much to disassemble. And at least you will know more about your vehicle. O ya change the oil since your working on it anyway a 10mm ,12mm screwdriver and pair of pliers also a torque wrench but you can borrow one from a parts storeHave fun with it and you should only be into it $150 max