Random multiple cylinder misfire???

Stieh101

Member
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2001 Protege LX 2.0
Wondeing if anyone can help.

I have a 2001 Protege LX 2.0. (Manual Trans.)

About 2 months ago I started to have problems with the car when I was stoped. It had very low rpm's and a rough idel. The car was also hard to start if it had been running for a while, but if I let it cool it would start fine. Also the car would never stall, just felt like it wanted to. The CEL finally came on after about 1 and 1/2 weeks of this. Took it in and was told that the spark plugs needed to be changed. Changed the plugs drove it for about 2 days and then it started again. Although this time it had very poor acceleration. Took it back to be checked again. I was told the EGR valve and PCV valve needed to be replaced. The codes were P0401, P0300, and P0506. So I changed the EGR valve and PCV valve. Got it back and a day or so later the same thing was happening. So I put fule injector cleaner in thinking it may be the injectors. No luck.

The problem is now intermitant, and the problem is slightly different from the first time I noticed anything. Now the car will drive fine one second and the next it will have really poor acceleration and; low rpm's and rough idel when stoped. I can drive for a bit like that and then the car goes back to normal. No rough idel or bad acceleration. When I get the really poor acceleration the CEL flashes. When it stops the CEL will stop flashing a bit later on. The car never stalls and is not hard to start.

I have also changed the spark plug wires and the air filter.

Does anyone have any ideas on what could be wrong?
 
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just as I was thinking spark plug wires you mentioned it. Did you replace them with Mazda wires or some "high performance" wires?

The flashing CEL is definitely the misfiring, I went through the same hell you are going through a few weeks ago when I got my plugs/wires all wet washing my car (note the massive gaping vent in my hood in my signature pic haha). I replaced the plugs, no dice. Ran fuel injector cleaner, no dice. Finally found a place with new wires for me, and the car was perfect. Make sure the wires are securely attached to the coil packs. When I was pushing my new wires on (with lots 'o dielectric grease all over the boot) they didn't like going on because they were sealed so well that I was just compressing the air when I tried to push them on. Once I managed to release that compressed air I could push them on farther and got a nice seal. Make sure they are sealed well onto the plugs too.

Good luck getting things up and running, and welcome to the forums! I'm so sorry that you had to come here while going through that hell though.
 
I'm trying to figure out whats going on with mine also but it isn't as bad as yours. I changed plugs, wire, and switched coil packs. Mine still reads cyl 1 misfire. It only happens after I drive it hard (mountains runs). I'm starting to think it may be fuel related but I have no clue. I have some replacement fuel injectors that I'm going to try and I'll post if it works. I'm also going to clean out my EGR again. There was another valve on the intake/throttle body area that was said to help when cleaned but I'm not sure which it is at the moment.
 
The plug wires were replaced with Mazda wires. I will check to see if they are sealed well.

Thanks for the advice.
 
If you changed the EGR yourself make sure it is well sealed too. There's a thin metal gasket between the intake manifold and the EGR valve that I dropped on the ground when I removed my EGR so I put it back on without a gasket and my idle was really rough and I could even get the car to stall if I took it up to high RPMs in any gear and then pushed in the clutch and cut the throttle abruptly.
 
I had the exact same problem with Protege, which is the exact same eveything as Stieh101, about this time last year. I had to pay out the wazoo to have all 4 injectors replaced.
 
^^ I'm lucky it didn't come to that for me. Wow this thread it attracting a lot of new members to this site :)

Am I the only one who came here because I love my car, not because it broke on me?

One of these days I plan on inspecting my injectors (probably when I next change my oil at 77500 miles) to make sure they aren't all nasty from the day or so that my car was barely driveable with the multiple cylinder misfiring.

Here's a thread to check out: http://www.mazdas247.com/forum/showthread.php?t=112359 <-- from that thread I was just reminded to ask what brand plugs you used? The cheap NGK v-power ZFR5F-11 seem to work the best in our cars, or you can go with the stock BFR5F-11 (basically the same plug, just not long reach.. the ZFR is the stock in Japan, the BFR in the states). DO NOT BUY BOSCHE plugs, they really don't seem to mesh well with our cars.
 
I'm going to have to check out which brand of plugs were put into my car. Long story short, I had the fuel injectors replaced soon after the spark plugs were replaced for the exact same check engine code. The check engine light came on last Saturday. Luckily, a couple of the o-rings are defective, which are being replaced under warranty on Friday.
After reading this post, I'm really starting to wonder if there are any other owners out there who have had the same problem.
 
Most of the people on here that I've heard talk about misfiring in my years on this forum had it from crappy aftermarket spark plug wires or using Bosche plugs. I've never had an issue with my NGK plugs (aside from getting badly fouled when my crappy aftermarket plug wires went bad).
 
Mine started with stock wires, I replaced the with densos, then NGK, and I only use good quality plugs, and I still have that problem. Just not as bad as some of you.
 
Same problem

Not to be repetitive---

I have excately the same symptoms (still do to a small degree).

Took it to a mom and pop place that ultimately threw-up their hands and gave me my money back (did the plugs, coils, etc..).

I pulled th EGR valve and cleaned it--it was stuck open with carbon buildup. car ran PERFECT for 1 month--not I have a check engine again. Not great excelleration (not horrible) and an idle speed of about 550--just enough to set-off the check engine light.

please help.
 
i had a misfire problem a while back. first off the wire to plug #4 was not snapped in all the way (you can actually hear a snap when its in place). after i popped that in place fully i was able to get it home without any issue. i had another slight misfire a few days later, and i replaced the coil packs. have not had the slightest issue since then.
 
Okay here is the latest update with my problems.

First off I did not change the EGR valve myself. With the exception of the spark plug wires, all work was performed by Canadian Tire. I did check the wires to see if they were well secured, and I was able to push them further onto the plugs, but it didn’t seem to help.

I do have a couple questions. Should I check the coil packs to make sure they are snug to the plugs? Also, I have been reading a bit about a “Safe Mode” where the car will run “rich”. What exactly is this safe mode and how does the car act when this happens, and can the car go back and forth into this safe mode.

I am taking my car over to a friend’s house tonight so he can have a look. He is a licence mechanic with a pretty sweet set up at his house. Is there anything I should suggest he looks at?
 
Im actually having the same problem now with the flashing CEL. Some days it'll flash and other days the CEL will constantly stay on. Further throwing me for a loop, I have the 1.6 liter Injen CAI, which is known to throw CELs. So besides swapping out the plugs and wires, what else could be done to get rid of a CEL?
 
For anyone interested, here is the latest on my car.

I took it to my friend so he could have a look. Well it took us a while but we finally got it to act up. So what he did was while the car was running we pulled out the far left spark plug wire and nothing happened. There was absolutely no spark. We pulled the other plug wire (3rd) and sure enough the car was running even rougher and you could tell that plug had a spark. So we switched the coil packs left for right. Of course we couldnt get the car to act up again at all that night. So yesterday it started so I checked the 3rd plug wire, and sure enough no spark, checked the first one and yes it did have a spark. So I figure it is that one coil pack that is bad and needs to be changed.

I have another question though. Here in Canada the Coils are aprox. $150.00 but I saw them at Auto Zone in the U.S.A. for only $17.99. Does that sound right to anyone? $17.99 seems too cheap.
 
$17 is correct.
you can also order them from rockauto.com (which is where i ordered mine from) $17 there also.
 
um wow? so the 17.99 ones are a-ok, decent quality? I will buy them today if they are. I'm at nearly 75k miles so it'll probably be time to replace them soon anyway, but my idle is low and a bit rough after my crazy misfiring incident a few weeks back.

Oh and yesterday it was raining pretty heavily all day so my car got pwned by it's massively open hood yet again and I was doin a little misfiring for the first half mile or so of driving. No CEL this time, though the code is still stored from last time I'm sure. Is autozone one of the places that'll pull the code for free? I wanna write them down just in case something weird is stored in there.
 
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