got a 91 si. keeps overheating. put every temp thermostat in, tried no thermo. did a pressure test lost no pressure. heater quits working also. but then sometimes like today, drove for 30 minutes gauge didnt move, heater worked right up till the end. also sometimes idle engine sensor wont quit revving up when overheating. but like earlier today everything ran fine. think it may be small head gasket leak, blowing combustion out, not taking water in, cause no white smoke. water pump replaced not to long ago while doing timing belt. help before i blow it up. gotta get to work

 

well you did everyting i would have done.. could be a head gasket. is your guage workin right? sometimes it doesnt heat up at all and sometimes its way to hot? if it still got hot with no thermostat there is a serious issue. haha. isthere oil in your radiator? take off the oil cap and see if the oil is milky... let us know

 

Yeah the guage is working, cause when it heats up, steam shoots out the reservoir, coolant isnt oily, oil isnt milky, just burns away water, cause got no leaks, and no white smoke, has bubbles in the radiator when cap off

 

shouldnt get bubbles..

 

I know I shouldent have to say this but did you bleed the system when filling it? And are the fans coming on?

 

I back pressured the system, threw the heater core supply line and had water coming out every opening, so no blockage i assume. right now i have to warm it up in moring wait for thermo to open, then top off water, wait for it again top off. then get to work quick. then do the same thing on they way home. I'm getting a top end kit from Honda Dealer for $135( i got hook up, regular price is $220)everyone should get hook up, you wouldnt believe the mark up. I pay cost plus 10% and it's unbelievable. I got fan motor for like $120 I couldnt believe that little **** cost like $250. But I'm doing work monday. My dads mechanic at Local Chevy place, so we get to do it right in shop shouldnt take to long. Never done this anybody got time frame idea/ i'll let yall know turn out. Thanx for suggestions. This better be it cause I love my baby. After this works , going for upgrades, where should i start, 91 Si. last of the best body(my opinion) i think they should have kept pop head lights i love then. wish me well

 

Also, any thing i should do to head while i got it out, shave it? any thing, I wont this thing to hum when i'm threw. thinking bigger injectirs fuel rail and throttle body.