2.4 overheating with heater on - Maintenance and Repair Forum

Forum Post / Reply
You must log in before you can post or reply to messages.
2.4 overheating with heater on
Monday, August 31, 2009 12:59 PM
I just installed a low mileage used engine in my 00 cavalier and has been running at about 195 temp wise since i got it back on the road until today when i used the heater for the first time. I noticed the car not blowing heat way after it should have been warmed up enough and then the temp started rising almost to red line and the check gauges light came on. I turned the heater off and by the time i was somewhere i could pull over the car was back down to around 205 and stayed there. I have anew water pump and T-stat and flushed the system with all new coolant. could i still have air in the system? I'm going to try jacking the passenger side of the car up and let it run with the cap off and see if that helps any but other than that I'm out of ideas.

Re: 2.4 overheating with heater on
Monday, August 31, 2009 1:09 PM
blocked heater core or air in the heater core. In my opinion.



PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
Re: 2.4 overheating with heater on
Monday, August 31, 2009 3:21 PM
Yes. You still have air in the cooling system, Do this pop the coolant cap off the resvivior, Make sure u are mixing the coolant 70% / Water 25%. Then with the rad cap off, Allow the car to reach normal operating temp, The for 10-15 mins rev throttle peddle around 1,000 to 1,500 rpm , every 2 mins, That should get rid of the air in the system, I had the same thing happen to me last year. Its common on these cars. If it doesnt work, Then I would look into the cooling system for other problems like: Hoses, water pump / etc.

Good luck.
Re: 2.4 overheating with heater on
Monday, August 31, 2009 5:04 PM
rich weeks wrote:Yes. You still have air in the cooling system, Do this pop the coolant cap off the resvivior, Make sure u are mixing the coolant 70% / Water 25%. Then with the rad cap off, Allow the car to reach normal operating temp, The for 10-15 mins rev throttle peddle around 1,000 to 1,500 rpm , every 2 mins, That should get rid of the air in the system, I had the same thing happen to me last year. Its common on these cars. If it doesnt work, Then I would look into the cooling system for other problems like: Hoses, water pump / etc.

Good luck.


i went out today and the reservoir was below the ''full cold'' mark so i started the car and added coolant/water until full and let it run with the cap off while revving it at random. I then turned the heater on and it blows very hot air and the temp does not increase while at idle so i think my problem was that the heater core was empty from having it unhooked and using the heater took coolant away from the system allowing the car to over heat. So far so good but I'll find out if it worked the next time I drive it and use the heater.
Re: 2.4 overheating with heater on
Monday, August 31, 2009 9:47 PM
yep, it can be that simple, good luck



nwuonline.com
Proud member on JBNW.org
JBO member since 2004
Re: 2.4 overheating with heater on
Tuesday, September 15, 2009 3:35 PM
Your electric coolant fan should have kicked in well before the red line. Put the AC on and see if the coolant fan is moving ('cause they run together).
Re: 2.4 overheating with heater on
Tuesday, September 15, 2009 3:40 PM
Other than that a coolant leak will cause the car to run hot and the 2.4 L motors are known to leak coolant from the water outlet on the driver's side of the motor and from the heater hose pipe at the back of the motor and underneath. Should there be no leaks than it's probably your water pump. The 98 model year has known water pump problems that is why for the 99 cavalier z24 model year there is a different style water pump. Cheers.
Re: 2.4 overheating with heater on
Tuesday, September 15, 2009 4:02 PM
thanks for the reply but i fixed the car the next day. turns out the heater core was empty form having the system open and when i used the heater it filled the core making the cooling system low on coolant. filled it up and ran the car with the fill cap off to burp any trapped air and it has been working perfect.

and just to recap the coolant flange and water pump were replaced with new parts while i had the engine out.
Forum Post / Reply
You must log in before you can post or reply to messages.

 

Start New Topic Advanced Search