So, a few days ago a co-worker brought me his 1998 Oldsmobile Regency. It has the 3.8l v6 (not the supercharged 3.8 everyone wants.)
His explanation of what happened was, “I was backing into my driveway and noticed the temperature gauge was starting to climb. After I shut it off, I tried to restart it but all I got was a pop and a puff of smoke from the exhaust.”
Upon arrival (trailered,) I gave it a shot of starting fluid to see if the motor was just sharing enough compression to keep from starting easily. There was NO water in the oil.
After doing a dry compression test the results were;
Cyl 1-90psi Cyl 2-150psi
Cyl 3-90psi Cyl 4-150psi
Cyl 5-120psi Cyl 6-90psi
These results are consistent with a head gasket failure. However, having low compression on one whole bank and one cylinder on the other bank was an eyebrow raiser. My next thought was timing chain. I pulled the left bank valve cover and all the rockers are moving.
As of this point, I know the timing chain is NOT broken, but what are the chances of it jumping time?
Side note, I know the car well as I am his regular go-to mechanic, and it has never had signs of missing on any cylinder. That’s why I find it quite odd that both banks show dead cylinders simultaneously.