Hi everyone! New to the board. I have had an 88 929 for the past little while and it has two problems I hope someone could help out with..

1. The engine 'searches' when idleing between 700-800 rpm every second or so ( up/down, up/down, up/down)and seems quite weak. The timing belt was just done, seals were done and the timing has been reset to spec..seems worse then ever..there's also always engine vibration through the steering wheel.

2. The car shakes when going down the road starting around 50kmh..all 4 tires have been balanced (twice)& apparently the rims are straight! It's felt mostly in the seat. Could it be bad tires? Or is the shuddering possibly caused by those scary et/at trannies? ( which seem to take their time getting into gear, ANOTHER problem??)

What a not-nice driving experience! After reading about all these Mazda problems in this forum, I think in buying Mazda I might have made a poor car brand choice! Anyone care to help change my mind & make me feel better?

The 88 929 was a great car,the transmissions were pretty much bulletproof. Check the modulator valve on the side of the trans for internal leaks. Remove the vacuum hose from it and see if trans fluid is inside the hose.
Buy a can of flammable carb spray and spray it around the intake/etc at idle. If the idle speed changes you have a vacuum leak. The intake tubes have large o-rings on the bottom where they pop onto the intake that can leak.

Thanks for the quick reply and confidence boost in the 929 ..I'll try your suggestions 1st chance I get!

my mazda 88 332 i start my car an it runs but when i shift it to second gear it shuts off im getting grrr i need help im used to working on older chevys an not this new stuff people are saying fuel injecter i have no clue HELPPPPP ASP

Chris, you might be better off starting a new post for a separate problem!

Probably not tyres, has the problem only started since you changed your timing belt? Could it be out one tooth? I had an early model V8 once with simlar symtoms and it turned out to be some weak valve springs but I doubt this is your problem!

I have had an excellent 89 model 929 for close to a year now, and I love it. It has had a few minor problems, but nothing I wouldn't expect on a car of this age, and nothing I couldn't fix cheaply.

The AT on mine played up a little, but was fixed by a $100 service at the local transmission shop (caused by a loose filter I think, symptoms were slipping unless the fluid was overfilled). The transmission does take a second or two to engage, and you can feel the changes, but all in all its pretty good for the age.

When I was looking to buy, I tested several higher miles 929's of similar age, and most of them had some light engine vibration which you could feel through the floor and the steering wheel, but of the type that you would get used to quite easily.

If you have a road speed related vibration, which doesnt change with engine revs (if you drop the transmission down to 2nd you will see it quite easily), it is the tyres, either out of round, too cheap/flimsy for the car or out of balance.

Finally, are you sure the right hand bank is timed correctly? As long as the left hand one (the one with the distributor) is correct, the the ignition timing will be fine regardless of whether the right hand bank valve timing is correct or not.