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Don Knight
Don Knight , ASE Certified Technician
Category: Pontiac
Satisfied Customers: 1736
Experience:  40+ years all makes&models
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1990 pontiac grand am: ho 2.3 16 valve quad 4 dohc..manual trans)

Customer Question

how to set timing on a 1990 pontiac grand am ho 2.3 16 valve quad 4 dohc hi output motor (manual trans)?
Submitted: 6 years ago.
Category: Pontiac
Expert:  Don Knight replied 6 years ago.
How are you trying to set the timing? This is an intergeted system timing is controlled by the spark control module.Are you sure this is a 1990 model? I'm sorry but I am a bit confused about this application. Any more information could be helpful.Thanks,Don
Customer: replied 6 years ago.

i am talking about when you remove the timing case cover and you have 2 cams , then you have your crankshaft & water pump,sprockets, with the timing chain & tensioner .

I took the chain off, then i rotated the crankshaft to top dead center.

Now the book says to rotate the crankshaft 90 degrees back off the timing to give the cams space to move.. Then i rotated the cams clockwise, to their posisitions , then i rotated the crankshaft 90 degrees back to top dead center. Then i put the timing chain on the exhaust cam and crankshaft & turned back the intake cam, so when i put chain on there willl be no play. Then replaced tensioner.

Was i suppose to retard the crank or advance it?

The car won't stay running, it backfires out the exhaust pipe & the throttlebody. ??


Expert:  Don Knight replied 6 years ago.
The crankshaft key should be at 12 o'clock the cam gears have a locating pin hole that should be at 6 o'clock I usually put a bolt in each hole to keep them aligned.The crank shaft key way should align with a mark on the engine block.If this aligned and you have pins (or bolts) holding the cam gears in place the rest should be easy.Just put your guides in place and then your tensioner & you should be good to go.If this has answered your question please check accept so that I may get paid.Thanks,Don
Don Knight, ASE Certified Technician
Category: Pontiac
Satisfied Customers: 1736
Experience: 40+ years all makes&models
Don Knight and 4 other Pontiac Specialists are ready to help you
Customer: replied 6 years ago.

did that and still backfiring. will start on its own but still doesn't stay running and makes a rough combustion / uneven really bad and goes "rummmm put chuck pop", you hear each cyl. but its like one is hard going.....and it don't !!???? put fresh gas and all in car.


Expert:  Don Knight replied 6 years ago.
Check your ingition module and the "holder" for the coils it is a white piece that connects the plugs to the coils this piece some times shorts out.It is available at most parts houses.Good luck ,Don

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