Staged
20+ Year Contributor
- 76
- 0
- Apr 16, 2003
-
Beaumont,
Having low power and boost is dragging horribly with a serious tapping at the lifters........
Replaced CAS, elimination kit installed, replaced turbo, replaced wastegate and did the washer mod, replaced knock sensor, replaced lifters with revised set, pulled the head and had the valves and guides inspected - looks good.
Set CAS in center and attempted to advance and retard it to tune. Set it back at center with no results. Oil loss caused the front balance shaft bearing to freeze. So I did the elimination kit to solve that in a hurry.
Suggestions took me from replacing the turbo to following 31 pages from the service manual on cam and crank timing and resetting all timing marks. Three times. For the junk of it, removed the A/C compressor and A/C fan to get at things easier. Placed a gauge at the head for oil pressure and get a 45 idle / 60 @ 3000rpm reading. I set the timing and had 4 different people check all my work from the torqueing of the head bolts on out to timing belt marks and now the cam marks look like they are off by a tooth each maybe. I can set one now where the dowel pin is exact and the other is out of place suddenly.
My next step is to replace the timing belt and tensioner tomorrow. What else could it be? Could that alone cause the tapping? And am I correct in thinking that the tapping could be setting off the knock sensor and in turn, be telling the ECM to retard the timing so far that it runs like total junk? How probable is this theory? And what other theories can there be?
Replaced CAS, elimination kit installed, replaced turbo, replaced wastegate and did the washer mod, replaced knock sensor, replaced lifters with revised set, pulled the head and had the valves and guides inspected - looks good.
Set CAS in center and attempted to advance and retard it to tune. Set it back at center with no results. Oil loss caused the front balance shaft bearing to freeze. So I did the elimination kit to solve that in a hurry.
Suggestions took me from replacing the turbo to following 31 pages from the service manual on cam and crank timing and resetting all timing marks. Three times. For the junk of it, removed the A/C compressor and A/C fan to get at things easier. Placed a gauge at the head for oil pressure and get a 45 idle / 60 @ 3000rpm reading. I set the timing and had 4 different people check all my work from the torqueing of the head bolts on out to timing belt marks and now the cam marks look like they are off by a tooth each maybe. I can set one now where the dowel pin is exact and the other is out of place suddenly.
My next step is to replace the timing belt and tensioner tomorrow. What else could it be? Could that alone cause the tapping? And am I correct in thinking that the tapping could be setting off the knock sensor and in turn, be telling the ECM to retard the timing so far that it runs like total junk? How probable is this theory? And what other theories can there be?
