shutter under accelerated load.

[jabartram]

well, i have a strange situation going on, it started yesterday, under acceleration as in speeding up on the freeway to pass or move over the front end feels as if it is shuttering, if i stay at a steady cruizing speed it is smooth or if braking it is smooth, it only shutters under accelerated load, tranny temps are normal, i put it in the air (with a jack) checked axleshafts and all front suspension components everything looks great, my drivers side inner cv boot is spitting grease but its not split, i did do a full reprogram of my pcm late last week, and i may program back to stock just to check. and the only other thing i did recently was tighten all my header bolts. has anybody else experienced this? any ideas of what to look for?

[[ion] C2]

misfire, spark plugs

[CharleyO99Alero]

***

Yep ... most likely a bad spark plug or 2.

How long since you last changed them?


***

[super white alero1]

I doubt its a misfire, can you get me some codes. If it says TCC where in the read out. please take it to your local tranny expert.

[jabartram]

no, no missfire, i'm a career mechanic, i would be able to feel a missfire, just not a mechanic for transmissions, my car runs top notch, thats why i'm so puzzled about this problem, i checked cods and there are no trans codes, just my normal enrichment codes from tuning. it almost feels like a slightly bent axle shaft or loose lugs but the lugs are fine, and i havent hit anything to cause an axleshaft to bend??

[super white alero1]

If axles you would hear a clunk during steering, might want to run a quick overall check on the tire, see if you find any deformities. I doubt its the cat but run the car at idle and see if you feel restriction in the exhaust. Tell me what you find, I'm interested in car puzzles :)

[Spilner521]

Torque converter maybe, or slipping clutches in the transmission

[jabartram]

If axles you would hear a clunk during steering, might want to run a quick overall check on the tire, see if you find any deformities. I doubt its the cat but run the car at idle and see if you feel restriction in the exhaust. Tell me what you find, I'm interested in car puzzles :)

i have no lack of power what so ever, tires i have checked and they are fairly new, my car never gives me issues, its pissed about something right now?

i'm wondering about my motormounts? and possibly front struts, struts have been on for aprox 4 yrs and they have been rode hard!

[jabartram]

Torque converter maybe, or slipping clutches in the transmission


transmission still shifts rock solid? cars pulls hard, just shutters/wobbles? i'm a bit lost on this one?

[super white alero1]

Curious about this, at under moderate acceleration? heavy acceleration? When you @ 55mph and gas does it shutter, or does it do it under any speed? If 55 or above and this acts up, it could be lock up solenoid that is faulty, if any speed, then your valvebody may need rework.
Note I don't believe its the mount, you would feel it at each and every shift point.

[jabartram]

cruising on the freeway with light throttle it runs smooth, if i throttle it to speed up it wobbles (lets romove the word shutter), back off the throttle and its smooth again, i was thinking weak motormounts could cause the motor to torque back to far and cause extra stress on the cv joints under acceleration? i'm looking at all possibilities, if my trans was running excessively hot i would be more concerned about the tranny, but the trans temp never got warmer than 175. at lunch today me and three other guys went to eat, we took my car and under hard acceleration getting onto I37 it started shaking pretty hard until the power leveled out, on the way hom with only my son and myself it barely did it??

[super white alero1]

I still don't thinks its the mount, There is one more thing I would recommend before i shut-up. Change both the axles, I don't think the axle is the problem but unless I had the car, blind troubleshooting is all you got. Axles from World-Pac runs about $60.00 new (EMPI, Cardone Select, etc) each. Hope ya figure it out, post teh results too.