6 MPS has developed a slight miss

[Penguin740]

It seems my wonderful 6 MPS has developed a slight miss in the engine.

The miss is noticable when on moderate throttle and low boost. It's not a strong miss but annoying.

On full throttle and idle it appears to be fine.

Does anyone have an idea of what this could be cause by? eg Could a bit of injector cleaner possibly fix it? Could it be just the realtivly new exhaust and pod filter playing with the mixtures (which will be sorted when Chiptorque chip it) on the otherwise standard car?

Any help would be appreciated before I take it in to Mazda to have it looked at.

[shakespeare]

Hmmm, not sure here, probably need some more info - What RPM and in which gear does this occur? I tend to get with mine (if I forget to downshift) a bit of mild hesitation when I accelerate around 2000rpm in 3rd or above, so now I always downshift as you don't want to put excessive load on the motor.

[Mr Nasa]

intesting, is it like a jolt?

[Syd_Chrome]

If it is like a flat spot, it maybe a dirty MAF sensor. Worth a look?

[Ranton]

Maf Sensors or dead 02 sensors account for more problems than people care to think

[Penguin740]

I'll have a look at the MAF sensor first.

The O2 sensor could be a possibility as well due to the exhaust shop finding that the person who removed it at mazda had stripped the thread and is currently holding on with just a few turns. 2XS was pretty sure it would be fine until I find a replacement.

[Penguin740]

I cleaned the MAF and IAT today (as well as 2 other Mazda's in the carpark at the time).

I have gained throttle response back which had dropped off and can't seem to notice any roughness anymore. I will keep an eye on it and see how it goes after a few days.

Thanks all for the help. I'm off to hunt v8's.....

[LILZLR]

Maf Sensors or dead 02 sensors account for more problems than people care to think

+1 Very true. .

[Penguin740]

Well it appears that the miss is still there and seems to be getting worse.

Shakepeare, The miss is most noticable between 2500-3000 rpm in 3rd and 4th gear.

I suspect it is occuring lower as well but aggree with you that I prefer to keep the engine well above 2000rpm.

Any further ideas?

By the way how do I check or clean on o2 sensor? Can a complete novice do this job?

[spastic]

could it by any chance be boost cut?

---------- Post added at 10:06 AM ---------- Previous post was at 10:05 AM ----------

Ryan's mps "mpsi" was getting boost cut in his car b4 chip torque tuned it for him?? just an idea