Hello everyone!

I've read the FAQ and stickies, but I'm new to the forums - apologies if I mess something up.

I have a 1986 Honda Civic DX. I've noticed two problems, which may or may not be related, and I'd love some ideas troubleshooting them. They are:

1. The temperature gauge is running very high - when hot, it rests at 50% to 80% of the gauge range, so while it's never in the red, it still seems very hot.

2. Before it heats up (~5 min), the engine dies very easily. It takes a lot of gas to keep it from dying when I start it, and if I stop at a stoplight the car often dies. Sometimes giving more gas prevents it from dying, sometimes it's too late and it sputters and dies anyway. It can be hard to accelerate during this time frame. After it warms up, there aren't any problems.

Regarding the overheating, about a month ago the engine starting overheating so badly that the gauge would pass the red and go off the scale. I did some troubleshooting and discovered that the fan wasn't coming on due to a faulty thermosensor. I replaced it, and now the fan comes on, but it still seems to run very hot - I'm not sure, though, since I'm not sure where the gauge is supposed to rest (30%? 50%? 70%). Around the time that this occurred, I had jumped the car but reversed the cables, allowing electricity to flow through the circuits backwards - it occurs to me that this may have been what caused the thermosensor to fail and potentially other parts of the vehicle (it blew a fusible link, which I replaced).

Any ideas? Does the temperature gauge in this era of Civic generally read that high, and there's nothing wrong, or does that sound too high to you? If it sounds too high, any thoughts about what could be going wrong?

It's possible that the underpowering could be a result of a lot of things - a vacuum leak, maybe - but I'd love to hear your thoughts. Anything I should check? I've gone through the factory manual but didn't see anything obvious and would appreciate any guidance.

Thank you!

 

the underpowering problem could also be the choke staying closed. the temperature does seem high i would take out the thermostat, and either check that it is opening in some boiling water, or just replace it.

 

The gagues are designed to show about halfway normally, but they aren't really calibrated to anything. You should check that the needle goes all the way down below Cold with the key off, and doesn't move much from there when the engine is cold. The important thing about engine temperature is that it should NOT vary once warmed up. Going uphill vs downhill or sitting still it should always be the same on the gauge.

 

Thanks for the information, guys.

The needle does go all the way down below cold with the key off, and as the engine heats up (takes 5 minutes or so), gradually comes up to about halfway. When in stop and go traffic or revving a fair amount in low gear, the needle can creep up fairly hot, around 70% - 80%.

Sounds like what I should check at the moment are the choke and the thermostat - I'll look into that in the next couple of weeks and post my findings when I get them. Any further ideas?

 

Hello folks,

For anyone following this thread, the issue wound up being a minor head gasket leak, unfortunately. Since it's not worth repairing, I'm going to try some head gasket sealant and see if that helps. Thanks for the help and advice!