Engine vibration/knocking/200 rpm idle

[Cool Mr Steve]

Alright, I was cleaning my valve cover when my cam gear ate the rag. When I tried to start it back up it ran very roughly and it sounded like it was knocking for about 4-5 seconds, then shut itself off. It looked as though the belt had skipped a couple teeth, so I changed the timing belt, threw it back together, did a compression test (about 173-183 on all cylinders) and tried to fire it up. Now it is only going for about 2-3 seconds with a violent vibration/ what feels like about a 200 or so rpm idle. What could it possibly be???

 

[Attack Eagle]

The CAS (cam angle sensor) which is under/inside the rear cam gear on a 95-96 GST. It's probably toast ...

 

[25psi]

Did you re-align your camgears and crank? Your mechanical timing is probably off.

 

[Cool Mr Steve]

Yes, I realigned everything when I changed my belt... Where is my CAS??? Can I see it easily to see if it is toast??? By rear cam gear, do you mean intake or exhaust... the one closest to the firewall, i'd assume... But assuming definitely never makes anything better.

 

[Attack Eagle]

Did you re-align your camgears and crank? Your mechanical timing is probably off.

all the vibration is from the 200 rpm idle...

Problem began when the rag got caught in the cam gear (btw good reason to run that cover ) and I am betting it was the one near the firewall, intake cam where the CAS is located...

ever notice how the intake cam gear has that piece on the back where as the exhaust doesn't? that is the hall effect wheel that the cas reads... Its under that cam gear somewhere...on the rear most side low i think...

I regret to say i have never messed much with the 95-96's just 1gs and 2gb... or ones that had converted to a passenger side cas for one reason or another...

when you idle at 200... any CEL? no spark on # 2 and 3? Limp mode is pretty much a 200 rpm idle...

ONe other thing... remove replace and wiggle the coilpack plug... see if that ahs any play or looseness in it.

 

[Cool Mr Steve]

ever notice how the intake cam gear has that piece on the back where as the exhaust doesn't? that is the hall effect wheel that the cas reads... Its under that cam gear somewhere...on the rear most side low i think...

Yeah, about that "hall effect wheel..." If it is the same insignificant looking 3 or so limbed piece of metal connected to the back side of only the intake gear, it got all bent to hell. I tried to straighten it out a little bit so that it wouldn't smack the head (when I first checked after my gear devoured that damned cotton, the metal was smushed against the head). Soooo... what you are saying, I think, is that this is an issue?

 

[Attack Eagle]

yep... the ecu compares that signal to the crank sigfnal... if they don't match up, random misfire and limp mode... I bet your 2 &3 have no spark... right???

gotta get that POS replaced... hopefully the sensor itself is ok...

 

[Cool Mr Steve]

Prepare for a stupid question... *Ahem*: Duhhhhh... How does I checks for spark?

 

[Attack Eagle]

pull the plug wire up when the car is running... you'll hear it sparking LOUDLY... and the engine will run worse...

If it doesn't... you have no spark there.

 

[Cool Mr Steve]

pull the plug wire up when the car is running...

Only problem is my car doesnt really "run" for any period of time, it just kinda "dies" for a very short period of time. Is there a way to test without it running?

 

[Attack Eagle]

slip a phillips in there and have someone turn it over while you hold the screwdriver (by the insulated handle) jsut above the valve cover...

 

[Cool Mr Steve]

Well, cam angle sensor = bad... Thats good news, though... maybe my car will be back on the road yet... Thanks for all the help!!!

 

[Attack Eagle]

no problem... just passing along all the help I receive.