chazla86

ok i picked upmy first civic 2 days ago i was wondering why temp gauge wuldnt work but niether was heater so after investigating previous owner bypass heater core bc it was leaking i put thermostat in and would run hot till i idled it up to 2200 rpms then it would dive down ihave no idea where to start ive heard it maybe water pump and then i have heard it could be blown head gasket please help

forted

Most likely your civic has a bad head gasket, next step is perform a cylinder leakage test

chazla86

how do i perform this test

JuggerNaut-CTR

Blow air into the cylinders and listen to where the air is escaping...if you need more than that, google "how to preform a leakdown test"....I got 25,500 results typing that in

breakinparts

Headgaskets seem to be the majority of cooling issues with these cars. If the heater core was bad it could have been due to over pressurization of the cooling system and found a weak point (should be the cap) You are fairly vague and we need more info for your problem

chazla86

yes heater core is bad when i got the car the temp would not move after some investigation seen heater hoses re-routed to motor decided to hook them to core and with in 2 minutes drivers floor board was soaked i bought new rad cap and thermo today trying to get car on road reliably commute one hour to work one way there is no water in oil and it is not smoking also temp gauge was unplugged i replugged it and with out thermo in it the car goes up to about normal till fans kick on and then down to cold

blkSi

Of course the vehicle is going to act funny without a thermostat. May need to start with a new thermostat and ECT temperature sensor (located on head, beneath valve cover, left side).

chazla86

i installed new thermostat and temp sensor is ok i think gauge is working but even after new thermostat it would get got until idled up to around 2200 then it drops back down no water in oil and car is running great besides overheating

kyden

did you bleed the cooling system after you added coolant?

chazla86

we bled it with new thermostat..... after checking heater core and after we bypassed it.... im pretty mechanicly inclined except withh honda's i love the car but need to know what could be possible problem and when i do replace water pump might as well replace timing belt who has the most affordable kit.....

blkSi

What exactly do you mean by "idled up to 2200"??

Are you sure you followed the correct procedure for getting all the air out of the system?

chazla86

i accelerated to 2200 rpms and held for 3-10 secs and temp started dropping im rebleeding cooling system shortly after installing the new thermostat then following instructions found via google will be back shortly

chazla86

thanks for that i took my time to put new thermostat in, car ran great drove it 45 miles round trip with ac going, It never went above normal and when i got home i let it run for an extra 15 minutes