Low compression,very poor performance

[Jim Ayres]

I just checked my compression and it's 80-90 across the board. Can this be a timing chain problem?

 

[SloGN]

low compression

yes the timing chain being stretched can cause that

on way to check for a stretched timing chain is to take the cap off of the cam sensor( leave the base in the motor) when you have the cap off the cam sensor turn the crank back and forth and watch to see when the cam senor wheel starts to turn. if takes excessive turning on the crank before the cam sensor starts to move then you have a streched chain


hope this helps

 

[pacecarta]

on a chevy or a pontiac the spin the distributor was the test that most used , but if the buick has the stock timing chain with the tensioner it wont tell you a thing

if you did the check correctly (engine warm , all plugs out , disconnect the ecm wire at battery disconnect the connector at the coilpack , battery fully charged starter known to be good, throttle propped open, spin for atleast three full revolutions and got 80-90
my guess is your chain jumped a tooth and if it's the original it may be because the nylon broke away and the chain is riding on the aluminum gear which wont last long , if you think it's the stocker in there plan on pulling it before it slips and does some damage like bent valves

 

[Jim Ayres]

I just pulled the timing cover and everything looked ok at first; dots lined up and all (Rollmaster double timing set) then I noticed that the bolt on the front of the cam was loose. I screwed it out by hand and removed the gear and the thing behind it and guess what I found?, The woodruf key was sheared off even with the front of the cam gear. I am hoping this is the cause of all my troubles. I will have to get a puller to get the cam gear off I guess, as it seems to want to pull the cam forward by prying on both sides of it.
Has anyone removed a Rollmaster setup off of a Comp hyd. roller cam?
Thanks,
Jim