my 89 camaro 305 tbi is running badly.sometimes it runs good and other times it misses badly at idle.on acelleration sometimes it backfires.i figure this means the advance isn't working.this car has the seperate coil and distributer.i noticed the center part of the distributer was really rusty so i sprayed some wd40 in there.it runs better part of the time and sometimes i think its going to stall.i have a chiltons and a haynes repair manual but they only cover the heis on the carb cars.where can i get a discription on this distributer and how it works?thanks for any help.

 

you should try and adjust the timing, and adjust the valves maybe, do little things like that to make it to the point where it should be running at its best, that way its easier to solve what exactly is wrong.

 

i'll check the timing if you think its nessesary but the distributer hasn't been moved.the car has non adjustible hydrollic lifters so thats not an option.

 

1) Your distributor is an HEI.

2) Check the continuity on each plug wire - maybe you have a bad wire - this will cause what you're describing - wire wiggles with engine vibrations and sometimes makes a good contact and sometimes doesn't. If you get a new set of wires, make sure to check continuity BEFORE you install them - they often are bad when brand new because the manufacturer doesn't test them.

3) Ignition Module - if all else fails, try replacing the ignition module - they are about $30, and they are inside the distributor under the rotor button - you mentioned rust in the dizzy, and and thus water has seeped in from somewhere, which could have messed up the ignition module.

3) Make sure all the plug wires are fully seated on the plugs and distributor, and staying there - I once had one that would back itself off - had to squish the end a tad with pliers - all the plug wires should 'snap' onto both the plugs and the distributor.

 

i cleaned the rapidfire plugs and tryed to owm the wires but i couldn't get a consistant reading.i bought the wires and in distributer module? last time when it did this last year.ive had several tbis and this is different.what controls the timing on this engine?does the computer do all of it?

 

Computer controls timing - you have to unplug the EST connector to adjust and/or get an accurate base timing reading (which should be 0*BTDC for a TBI car). EST connector is in proximity of the pass side strut tower, it'll be a brown or tan single wire with a connector in the middle that you disconnect. If your not getting almost full continuity on all the plug wires, I'd replace them.

 

I thought in 89 the BTDC went to 6* for the TBI?

 

Stock emissions sticker under the hood has the factory setting of 0* BTDC, you can set it higher and some do, but factory setting is 0* BTDC.

 

Hmm. I do remember reading years ago timing was moved to 6* in year 89. I know the shop I went to had it in their computer that timing is 6* for an 89 TBI. I wish I still had my factory hood to go look.

Would it by any chance be in the owners manual?