[Speedy3]

See thread here:
http://www.mazdas247.com/forum/showthread.php?t=123656333

Has anyone experienced heavy stuttering in a MS3 during acceleration especially in 3rd gear and up?

 

[quiet desperado]

[quote author=Speedy3 link=topic=66128.msg1133968#msg1133968 date=1167973623]
See thread here:
http://www.mazdas247.com/forum/showthread.php?t=123656333

Has anyone experienced heavy stuttering in a MS3 during acceleration especially in 3rd gear and up?
[/quote]

At best a hiccup, which I consider a positive since I assume it's what our turbo lag has been reduced to.

 

[CosmicBlueMS3]

first things that come to mind are a dirty MAF, dirty air filter, loose vac line, bad gas
do you notice anything weird at idle?

 

[betelgeuse]

No stuttering here, and I'm at about 4125 miles. Could be so many things like Cosmic mentioned. If you use the same gas station, try another.

 

[Speedy3]

[quote author=CosmicBlueMS3 link=topic=66128.msg1134166#msg1134166 date=1167998803]
first things that come to mind are a dirty MAF, dirty air filter, loose vac line, bad gas
do you notice anything weird at idle?[/quote]

I guess it could be a loose vac line or bad gas, but I have gone through quite a few tanks since it started hapenning. I checked MAF sensor and air filter and they look good. I buy Chevron 92, which highest octane available here in WA.

 

[betelgeuse]

This is something a dealer should fix. I know it's sometimes hard to find good ones but they do exist.

 

[Speedy3]

I took it in today for a test drive and diagnosis. The drive to the dealer was about 35 miles. I warmed up the car to normal operating temp before leaving. The car stuttered on accelerations for about 15-20 minutes, but after that it cleared up and ran very good and strong without stuttering or hicups. Got to the dealer and told the senior tech that it was running real good and the test drive might not re-produce the problem, but we went anyways. Test drive produced a couple of stutters/hicups, and ran real strong the rest of the time. It's funny taking a tech on a test drive, they don't even flinch when the car hits 95 MPH! The tech decided that the stutters he felt were justification enough to run a full diagnosis. He checked just about every sensor: MAF, Fuel pump 1 pressure, DISI pressure, boost pressure, engine temp, splark plug #1, O2 #2, No codes, Nothing found. Interestingly, I ran the tank almost to empty on the way in to the dealer today, so I put in a half tank of fresh Chevron 92 after leaving the dealer and man, I haven't felt my car run this good since I drove it home the day I bought it. It's running excellent and pulling very hard; put a big smile on my face. I don't know if it was something they bumped/disconnected&re-connected, the new gas or the master reset I did 2 days ago.

I'm getting my Auterra Dyno Scan SW in a few days, so I'm gonna log as much data as I can if/when the problem happens again.

 

[Speedy3]

Problem solved. I replaced the spark plugs today and found two of them with long cracks in the ceramic. The cracks are pitted and filled with carbon depostits. Now the car runs like new again. I have been dealing with the stutter for the past 5000 miles. I wen to the dealer 4 times and they couldn't even take the IC off to access the spark plugs without a CEL. Anyways, if you have a stutter issue in this car, check the plugs.

THIS THREAD IS SOLVED!

 

[dutchie3]

is it just me, or does that plug look like it has been in the car for 3 years. I pulled mine out of the accord after 50k miles and they were cleaner. you should see some ceramic white area with some slight brown from heat, if anything...

 

[DLUX]

I'm sure it's due to the fact that this car runs rich as hell in stock trim.

 

[mattleegee]

another washingtonian....

yeah 92 chevron is the best we can do

there are a few shops that run 96 octane

or you can buy 5gal barrells....

 

[Trubopower]

The dealer should cover that. Those are 75k plugs dont tell me they went bad after less than 5k mi. Rediculous.

 

[dutchie3]

yeah, more details speedy3.
did the dealer change them, if so, which one, warrenty....that is a defect.
still not sure a hairline crack in ceramic would cause that (which is very hard to see as the pic of the plug is very bad btw....)

 

[brecker]

[quote author=Speedy3 link=topic=66128.msg1246648#msg1246648 date=1172958609]
Problem solved. I replaced the spark plugs today and found two of them with long cracks in the ceramic. The cracks are pitted and filled with carbon depostits. Now the car runs like new again. I have been dealing with the stutter for the past 5000 miles. I wen to the dealer 4 times and they couldn't even take the IC off to access the spark plugs without a CEL. Anyways, if you have a stutter issue in this car, check the plugs.

THIS THREAD IS SOLVED!


[/quote]

I'm a little confused.. You said after the dealer did their complete check-up that the car was running perfect. But then you said 2 months later that you finally solved the problem with new spark plugs??

 

[jasno999]

This whole thing is confusing to me. I have noticed the stutter you are talking about but this spark plug thing is strange to me. Very hard to beleive that bad spar plugs are causing this issue and it is even harder to beleive that you had plugs that went bad that fast.

The car may run rish but it should not run so rich that it is fouling the spark plugs.... That is somethign that I think they woudl have to fix if it were truley the case.

 

[Speedy3]

[quote author=dutchie3 link=topic=66128.msg1249224#msg1249224 date=1173105225]
yeah, more details speedy3.
did the dealer change them, if so, which one, warrenty....that is a defect.
still not sure a hairline crack in ceramic would cause that (which is very hard to see as the pic of the plug is very bad btw....)
[/quote]

I brought the car in 4 times, they claimed everytime that they couldn't find anything wrong, in-fact, because there were no trouble codes, they couldn't go deeper into the motor. That day that it ran really good after I brought it in, yes, it ran perfect after I brought it in, but here is the issue I didn't pick up on right away. The stuttering was very prominent in the first 30 min or so of driving (after being warmed up). After that, it would be gone completely. This car warms up very slow. Once it had been driven for more than 30-45 min (hard especially), the internal temperature was hot enough for the engine to fire with a weak spark. That day I claimed it ran perfect after picking it up, well, the car had already been driven for an hour before bringing it in, so it seem ed to be gone. It always came back in the mornings on my way to work and in the afternoon on my way home. Remember, the temp here was in the 20's and 30's. I got tired of the stuttering and just ordered new spark plugs as part of my troubleshooting. It solved the problem. The dealer refunded my money on the spark plugs and vowed to send them to Mazda for inspection. They said that it has happened in the past that the plugs were fractured in assembly from either being dropped or just whatever? It runs f'n perfect now without a single stutter ever since replacing the plugs. It pulls way harder than ever before.

Check out this thread:

http://www.mazda3forums.com/index.php?topic=71472.msg1257353#msg1257353

"http://www.mazda3forums.com/index.php?topic=71472.msg1257353#msg1257353"

 

[Speedy3]

[quote author=dutchie3 link=topic=66128.msg1249224#msg1249224 date=1173105225]
yeah, more details speedy3.
did the dealer change them, if so, which one, warrenty....that is a defect.
still not sure a hairline crack in ceramic would cause that (which is very hard to see as the pic of the plug is very bad btw....)
[/quote]

Sorry, about the picture, I used a webcam cause my camera was upstairs. I added more. I had to use a magnifiing glass to get the close ups and it wasn't easy holding it all straight!

A hairline crack WILL cause stuttering. Think about it, a rich fuel mixture will require more heat to ignite. Combine that with a weak spark that is travelling from the anode, down the ceramic and sparking inside the barrel of the plug. As the heat increases in the cylinder and as the RPMS go up and time between the power stroke decreases, the ignition gets easier because the heat duty cycle is higher. This aligns with the symptoms. When the RPMS got above 5000, the stutters were gone because the rate of fire was so fast, that it was basically hot enough in the cylinders to fire with a weak spark. This happening in 2 of 4 cylinders will cause funky powers fluctuations.

 

[jasno999]

I have noticed the stutter at times myself. I thought it was happening only when I would get on the gas but then let off when I was in boost. I thoguht it was jsut me lettign off the gas but I have noticed a few times when gettign on it and keepign the pedal down that the car sometimes has a stutter as it accelerates....

WTF

 

[JimmyMac]

I got alittle stutter right now. Just actually started this morning when I cranked up the car. Sounded like it was missing alittle. But it gradually when away after I drove it alittle. Also, someone said my car had a poof of black smoke come out my car as I was cranking it up. Kinda had me worried. I was suspecting the plugs. And after reading this thread... it may seem so. I'll just check the plugs tonight or tomorrow after work. I'd go to the dealer. But I don't feel like driving 1.5 hours one way. Plus my car isn't exactly stock... hehe... Anyways, I'll report any findings by this weekend hopefully. Oh, did you torque your plugs? Or just do the 1/2 turn with washer or 1/4 turn without?

 

[JimmyMac]

Well took out the plugs.... Here are the pics. What do you think?

Here is the 1st plug;

Here is the 2nd plug;

Here is the 3rd plug;

And here is the 4th plug;