Hello, I have a 1998 Civic LX with a D16Y7 engine. It has 220,000 miles and the only major maintenance that has been performed is an exhaust manifold replacement (due to a crack) which apparently is a common issue with this model. The symptoms I have been having for the past week are as follows:
The temperature gauge starts to climb towards H while the car is sitting in traffic or idling for a lengthy period of time. When the car starts moving again, the temperature gauge retreats to normal operating temperature. The coolant level seems to be slowly leaking as I have added around ½ gallon in the past couple weeks. There is no external leak showing and there is no smoking in the exhaust. Recently, my car has had sputtering issues on cold start-up (usually after sitting overnight). The sputtering only lasts for a couple seconds and then the engine runs perfectly. One of these start-ups presented a check engine code of PO301 and P1399 (random and cylinder 1 misfires).
Any idea as to the cause of these symptoms? Thanks!
check for head gasket issues
I think you have a radiator fan that has not been working and you have ignored the overheating because it went away when you were moving. Now you have a leaking head gasket.