I have a Camaro that I just rebuilt the motor for. I just got it back from a shop and it runs worse than the first start up. There is a nasty clicking noise coming from the right side under the valve covers. I adjusted all valves for #1 firing position, then the rest at #6 firing position (not running). I started the motor and the noise was still there. I checked the intake for vacuum leaks and found none. I then checked timing and it was good. I took the car around the block to see if it would go away, but found that trying to give it a little gas made it sputter, and I checked throttle linkage, throttle body, air cleaner, IAC motor, the works and found no problem. The only thing I haven't checked is the fuel system, but I don't think that explains the clicking. I have brand new injectors and MSD ignition, so I don't think a misfire is the problem. I do have a performance cam, but the springs I have said they can handle more than the lift I've got. I'm a pretty competent mechanic, but I'm out of answers. I've put too much time into this car to give up on it, any help would be appreciated
This might sound stupid but is there oil in it, if so and you checked the rockerarms and they r ok, and you put a cam in it I would check the lifters and if there sticking it is possible I had it happen on my chevell I upgraded to roller rockers and lifters and it fixed the problem and added some horse power!
March, 12, 2007 AT 4:03 PM
Thank you for replying. I do have hydraulic roller lifters, full roller rocker arms, and hardened pushrods. It had oil when I had it running, about 30 psi at idle. That is high, but a seasoned gm mechanic I talked to said it isnt a problem with new bearings all around. I also checked the clearance of the guideplates and it checked out ok. I cant run the car right now because the shop that put in my oil pressure sender did a bogus job and it blew out on me on friday. Do you think my domed pistons could cause a misfire bad enough to be easily heard?
March, 12, 2007 AT 9:24 PM
It is possible but it would/ should sound mre like a harder sort of thud not a knocking like something is lose, do you have electric cooling fanc or a manual engine driven fan if so the bearings may be bad and you only hear it some times.
March, 13, 2007 AT 2:25 AM
I have electric cooling fans and the noise is there all the time. Cold, hot, idle, I can even hear it at 3000rpm. Its there when the fans are on or off. The noise sounds kinda like tapping your phone on the fender in rythm with the engine. The higher the rpm, the harder to hear, probably because of the sheer speed of the motor running. As soon as I get the oil pressure sender fixed, im thinking about trying to use aviation fuel (101-103 octane) to see if it goes away. Only thing holding me back is the fact that it is only coming from the #8 cylinder, none of the others.
March, 13, 2007 AT 4:42 PM
I just verified a miss on #8. The car sounds absolutely beautiful for running on just 7 cyls. Thank you for taking the time to help me out. Now that I know what the problem is, I can work from there. Thanks again.