Light hesitation at low rpm - still...

[viktor_k]

So I have replaced spark plugs, air filter, and checked for loose connection and what not, still getting a somewhat hesitating acceleration from 1500-2500 rpms & light throttle, i'm wondering if its just the nature of the motor, or it should be smooth.

Another thing I'm noticing (not sure if this is related) but sometimes when the car starts (cold) the engine kind of shakes, but not a misfire for sure, kind of feels like when you're doing 60 and the tires need balancing, but you're standing still. It goes away after you start moving and doesn't come back until next time, or some other time. I'm wondering if its the clutch, cause it does seem to be a bit too sensitive like the bearing is going out.

 

[Davicho]

For the hesitation there's a TSB available from Mazda where they reload new parameters into the ECM. I cant remember the TSB number but I know you'll find it if you search here. Unfortunately I've heard you loose a little bit of horsepower (157 down to 153) which sucks. Only reason I haven't done the update to mine.

For the vibration, I bet your right passenger side motor mount is toast. Check to see if there is any oil leakage or residue under the mount.

 

[ukulele]

I get the shakes too on my 2012 during warmup, I chalked it up to being your average 4 cylinder warming up, but could always be a bad mount I guess. Might have something to do with the highway vibration? (which came back by the way BUT it comes and goes... craziest thing ever). I will have my mechanic look at ALL my mounts during next oil change unless it warms up to at least 60 degs in which case I can do it myself outside. I was going to say about the hesitation, lots of people don't even do this but I like to take apart my TB and clean it with solution, sometimes the buildup of gases, oil and dirt will make the butterfly valve stick. I had a weird issue with my old Yaris which was common for that car, when you approach a stop light, your idle would go so low it would feel that the car wanted to shut off. I took apart the TB looking for the IAC valve but that car has no IAC and turns out the entire TB is a single piece controlled by the ECU, so I just gave it a massive cleaning and after reassembly it ran smooth like pudding after that, no more dips in the idle.

 

[viktor_k]

For the hesitation there's a TSB available from Mazda where they reload new parameters into the ECM. I cant remember the TSB number but I know you'll find it if you search here. Unfortunately I've heard you loose a little bit of horsepower (157 down to 153) which sucks. Only reason I haven't done the update to mine.

For the vibration, I bet your right passenger side motor mount is toast. Check to see if there is any oil leakage or residue under the mount.

Yea, I've read about the TSB, but the records for the car indicate that it was performed, but the sticker is missing from the A pillar like TSB mentions. So maybe i'll have them check it out. I would rather not get the tsb, if I know that it hasn't been flashed, then I will first try to shield that wire to see if it makes any difference.

 

[Robotazky]

Yea, I've read about the TSB, but the records for the car indicate that it was performed, but the sticker is missing from the A pillar like TSB mentions. So maybe i'll have them check it out. I would rather not get the tsb, if I know that it hasn't been flashed, then I will first try to shield that wire to see if it makes any difference.

How many miles does the car have?

 

[viktor_k]

77k.

 

[mazdadude]

So is the motor cutting out during the low rpm hesitation, or does it just lack the crisp response you are expecting?

My thoughts for possible issues on the 06-07 models...

1. The reflash TSB for the sensor error as suggested above.
2. There was a TSB for a cowl gasket / trim piece that allowed rain / carwash water to leak onto engine from the firewall / windshield cowl.
3. There was a TSB for defective / leaking motor mounts. This caused a hesitation feeling, and a cruising / freeway speed vibration.

Also, the motor mounts are used / abused a little more on the Manual Transmission models...