Hey guys! Saturday my wife experienced an overheating episode with our '95 Civic. She said that the temp gauge spiked and she drove 5 miles home, no heat from the heat or defrost, outside temps about 15 degrees. I checked the coolant (none) and the oil . . full with no bad color or foam. Figuring a stuck t-stat I changed it and re-filled with coolant. No leak, but after warm-up the engine now revs slightly from normal idle (about 800) to about 1200, up and down and up and down. Coolant clear, oil clean, what could this be? Gonna get a code check tomorrow at the parts store, everything is buttoned up, no loose wires, didn’t knock any vacuum hoses off when changing the t-stat, I checked it twice. Ideas? Rocketman
Driving five miles with the temp gauge pegged and no heat from the vents doesn’t bode well for the engine. These Honda engines don’t tolerate overheating at all. This engine just might be done.
I also forgot to add, if this vehicle has an automatic transmission, you’ll want to check the tranny fluid to see how badly it got burnt.
Tester
Ouch! I know what you mean, and no matter what you tell some folks, well . . . let’s just say I would’ve shut it off immediately, but that’s another story. Hopefully the 15 degree temp and short trip will make a difference. Transmission fluid is clear, I just changed it in July and no burnt smell. Starts up nice, no noises or smell, but the engine still revs up and down, up and down, up and down. Oil clean and full, coolant clean and full, gotta be a vacuum line . . . I’ll go over it one more time. Thanks Tester! Rocketman
If this car still runs after you add coolant, you should get the cooling system pressure tested.
How old is the water pump? Did you have it replaced the last time you had the timing belt changed? How long ago was that?
Thanks Whitey! I will get the cooling system tested. Turns out that the t-stat DIDN’T stick closed, my wife was teaching our daughter to drive and they ran over an ice boulder (hard as concrete in 15 degree weather) and didn’t tell me. I got it running and noticed a slow leak, the bottom of the radiator being cracked at the seam from the ice boulder.The leak ran the coolant along the seam and down along a piece of bodywork and I didn’t notice it, assuming that the t-stat was the culprit. So now I have a new radiator to replace tonight, a new t-stat with gasket already done, new coolant to go into the system. The water pump was done with the timing belt about 12,000 miles ago and should be alright. I’ll let you folks know how it turns out. Rocketman
“Engine idle rpm goes up and down.” Vacuum leak. Perhaps between the intake manifold and the cylinder head. Also, check the large intake tube for split, check intake tube for seal on either end, and pinch closed each vacuum hose (including ones to brake booster, cruise control, charcoal canister, gas tank) while the engine is running.
I’m not sure if this car has an IAC valve but you might want to test it and the connection to it. Just a thought.
You might be able to avoid a head gasket by re-torquing the head NOW…Do this after our fleet of Subaru’s overheated (for one reason or the other) usually avoided the almost certain head gasket failure…
What seems to happen, the aluminum block expands past it’s normal limits and stretches the head bolts…When the engine cools off, head bolt torque and clamping pressure are released…Gasket failure quickly follows…It’s worth a try…
Thanks for all of your comments. I changed the t-stat and gasket, changed the radiator and cap, fixed the plastic pieces on the front bottom (where the iceberg hit) torqued the head (only went a little bit, but I feel better) re-filled with coolant and checked the oil and A/T fluid . . . both clear. TEst drove about 1/2 hour, going out again later to pick up kids, everything fine. BTW . . the “loping” of the engine must’ve been that one vacuum line I bumped loose. All seems well, thanks again for your comments! Rocketman
Glad it worked out. I had to replace two radiators from 140k to 220k with my 95 Civic due to poor cooling capacity. I did run the car for 100 miles with needle nearly at H at 140k and it never bothered the car much.
The later road test worked out fine . . . runs just like before . . dodged the bullet. Life is full of these things, I guess. Thanks for all of your comments. Rocketman