Just had a head gasket job on my '98 XJR, in which they replaced a few hoses, a few belts, timing chain and guides and tensioners, water pump. When I got the car back, when you it warms up, you can hear a clicking noise. It is random. It is not the normal popping noises you get when the exhaust cools down. You can hear it inside the car when it is running. You can also hear it as it cools down after you turn the motor off. It sounds like the clicker they train dogs with. It makes no clicking sound when the motor finally cools down. At first I thought it sounded like an electrical arcing, and then like a loud relay tripping. The garage that did the head gasket job didn't have any good answers, and said that they thought it was just metal expanding and contracting with the motor temp. Can it be that simple? The car runs well and strong other than the clicking. Any info appreciated.

 

Just to be clear.....So the clicking noise is not present till the engine warms up, and is present when the engine is running after warming up and when the engine is turned off after warming up, yes? I was thinking relay, fuel pump?supercharger?.......Thanks Allan

 

Yes, it seems to be heat related. The engine has to be warmed up. No performance issues evident. Thanks.