Q: Engine compression 1989 Volvo 740

Hi There, A failing manifold gasket could certainly contribute to a problem with the engine starting, however this would not necessarily go away when it warms up since it would be a constant leak into the intake system, which would cause an imbalance in the air/fuel mixture. I would suggest having a professional from YourMecanic come to your location to perform a compression leak down test which will reveal whether or not your issue is compression related.

Hi there - the conversation with your mechanic, and the symptoms you describe are a bit incomplete for a recommendation with much confidence. Engine compression is unrelated to a "manifold" gasket issue for the most part. A leaking intake manifold gasket could cause a lean air/fuel mixture that would cause rough running and poor power. A leaking exhaust manifold would create a noisy engine, that might "seal" a bit when hot, reducing noise. A leaking head gasket would cause reduced power, loss of coolant in most cases, and rough running. If your engine is turbocharged, a leaking exhaust manifold could cause a slight loss in power, since exhaust gas pressure in turbocharged engines is used to increase additional power. Please expand on the information offered by your technician if possible so that we can provide a more meaningful and accurate diagnosis. Thanks for thinking of YourMechanic.com!