MX-3.com

Car: Mazda MX3 V6 DOHC 1993 Automatic
Problem: Sputtering Idle-3000 RPM - Sometimes sputter is so bad the whole engine shakes.
Desciption: I purchased this car around 7 months ago and it had this sputtering problem. No one was able to help me, but I've heard many suggestions. One of the most common suggestions was to replace the valve cover gasket because I have oil where my spark plugs go. I was told though, that if they had a little oil (Which I do, but the spark plugs are nearly covered with oil even though I have never seen much oil in there.) it was not the cause of the problem as long as it wasn't like halfway filled with oil. My impression is, if the oil doesn't go there it's bad that it is there.
I had my spark plugs changed at a mechanic 2 months ago. When they were changed the car ran fine for about a month and then the sputtering started to get worse. It doesn't make it undrivable, just difficult to accelerate out into traffic. The dealer said before the spark plug wires were new, but now is saying otherwise.

In the last 2 weeks I have changed:
spark plugs
fuel filter
air filter
pcv valve

I have bought to put on, but havn't done so yet:
oil filter
valve cover gaskets

After browsing the forums for the last few days I have foudn that these are some fixes that people have come across for this problem or things very similar:
check valve 6 for oil - valve cover gasket
change all the plugs, fuel filter, distributer cap, and button. Problem was three of the plug wires have cracks all the way down them. - I don't see cracks on my wires
distributor bad?
air intake (cracked?)
total fuel system cleaner
fuel injector? - my knowledge of cars lacks, but I don't think mine is fuel injected?
o2 sensor - only seen if check engine light is on, which mine is never, but the bulb for the light could be out
spark plug wires - mine look new, but may not be

What I need to do is try and minimize the money I spend because I'm pretty much broke as it is (Damn hurricanes). Would you please give me any information regarding a solution to this problem I would be very grateful. Feel free to repeat any information. As of right now the next thing I'm thinking of doing is pulling $100 out of my *** for some spark plug wires. Feel free to ask me any questions regarding this problem.

Thanks in advance!

EDIT: I Just now cleaned my spark plug "things" with Armorall Wipes (The rubber things that attach to the spark plugs and seal shut the chamber) and the sputtering decreased a little bit. Also, the back left spark plug rubber is damaged a little around the edge which MIGHT be weakening the seal. Do spark plug chambers need to be sealed tight or is that not important?
The plastic on the left side of the engine (when facing the car), nearest the front bumper, is not sealed. It looks a little bit warped and bent. It's not too bad, but if that must be air sealed tight it may be a problem. If you need a photo let me know.

<small>[ October 28, 2004, 01:19 PM: Message edited by: ttye0 ]</small>

Well, seems like you have a hand full of problems but I would point the main problem at the oily spark plugs. The previous owner must have drivin the crap out of the car and damaged the piston rings. Try to get a compression test done and let us know the results. If the compression isn't too bad, I would suggest checking the contacts inside of the distributor (rotor contact too). All you need is one cylinder to not fire correctly for the car to sound and run like a toilet. Let us know what you find...

Alright, on Saturday I have a friend checking the compression and a couple other things. We're hoping to figure out what the problem is, but there is very little hope for me I'll get back to you and let you know what happens. Everyone else, feel free to give more suggestions.

Couple of things in reply:

Yes, it is fuel injected.

The CEL should light when the ignition is turned on, before the engine is started. If it doesn't, you have a bad lamp.

Ok, the lamp is good. As far as I've been told, that limits out the O2 sensor.

the o2 rarely triggers a CEL. Mine never did, but they were the culprit to all of my problems.

you might want to look into those

I had almost the exact same problem...it happened last week. Gunk all over my front three spark plugs.

I resealed the existing value cover gasket with some extra sealant, its sputtered for a my next drive. But after driving it about 20k all the sputtering went away and its now been a week without a sign of the problem.

What a coincidence, but I'm experiencing the very same problem.
The car sputters , throughout the acceleration, less noticable at the higer RPM's , of course.
I've changed the distributor, which was very $$, the spark plug wires.
Sputtering is still there though, and is becomes obvious after the car is fully warmed up. Until then is runs fine.

I guess new plugs will be next on the menu.

Not to mention......I brought it to a Mazada Dealership, and they just aligned the timing for the distributor.......they didn't diagnose any other problems!

Does anyone know how to fix these cars ?

I do have the same problem right now, but once the check light comes on the sputter ends, I`m almost sure that what cuases this sputter on our engines are the 02 sensors, because once I`disconnect them the sputter ends, and after a short while the check light comes on.

When i had similar problems i changed my plug wires, plugs and rotor button like 3 times until i decided to just replace the disty and then the problems went away.

I changed the spark plug wires, compression test never happened, and 2 different people backed out of doing the valve cover gaskets for me. However, I did just notice that when it sputters there are two cylnder type black things near the rear of the engine area. Very visable, but mine are shattered open. Not sure what they are...but as soon as the sputtering stops and it kicks back in the metal rods that are attached/in them shift to the other side (right, facing the engine). I was wondering if there could be a vacume leak? I can't find it if there is. (I'm not too knowledgable of cars yet) Any tricks to finding vacume/air leaks?

Those things sound like the VRIS valve actuators. Check Page F2-100 of the online manual for description of when they operate. From what you've said, they could be operating normally.

Locate vacuum leaks by spraying cleaning fluid or starting fluid (kigass) around the suspect area. If the revs rise, the engine is sucking the fluid vapour in through the leak.

The online manual is back? Where have I been?