2001 EX overheating, multiple conflicting symptoms

MetroShop_2000

New Member
Hello all… I’m new to Civics (my buddy just bought one for his son). However, I’m not new to wrenching or online forums. Forums have saved me many headaches and money so… THANK YOU to all the pros on these sites that help us home mechanics out.

The car I’m helping out with is a 2001 Civic EX, 4 dr, A/T with 135k miles and apparently, according to the prvious owner, a new/rebuilt transmission. He just bought the car a month ago. Within days, it threw CEL related to the shift solenoid. I have since removed the solenoid and cleaned it, reinstalled and the CEL has been off since. Now he’s having overheating problems. I’ve read many posts on this forum as well as other forums, including great write-ups on overheating troubleshooting and the extensive post of diagnosing blown head gaskets. Breaking down the symptoms he’s having, they are related to various individual problems. However, I’d like to post all the symptoms together in case they cumulatively mean something else.

I’d like to thank all the pros on here in advance.

Last week, the temperature gauge shot up to the red then dropped to normal range within minutes. It continued to fluctuate.

The heater does not blow hot air.

It overheated 2 days ago. His daughter pulled over and had to add water to the reservoir tank.

I test drove it around the block for 5-10 minutes last night. Here are my observations:

-The temp gauge shot up to the red line and remained there.

-Heater not blowing hot air

-Upper radiator hose piping hot, lower hose barely warm.

-AC/heater actuator/blend door functions properly

-Fans operate properly

-Coolant leaking somewhere behind the drive belt (evident steam and sizzling sound)

-Visible drips of fresh coolant along the main crankshaft pulley where it meets the block

-Cap of reservoir tank keeps coming off while driving. The threads are good and able to get a solid/tight seal but keeps coming off while driving. It appears that it comes off under enough pressure to make it shoot up and fall in the area behind the battery.


I didn’t have the proper tools to diagnose anything further. I plan on going back tomorrow with an inspection mirror to see where the dripping coolant is coming from. I also plan on testing the cylinder’s and radiator pressures.

To the pros on here, do all these symptoms combined mean anything or was it simply a bad thermostat that cause much more problems (busted seal/gasket due to high pressure)? Regarding the dripping coolant, around the crankshaft pulley, does the actual pulley rest up against any coolant passages (would it be coming out of the pulley seal)?


I don’t think the coolant has been dripping in that spot for very long, there’s no old residue in the area. I’m hoping the overheating last week didn’t blow a seal or gasket. Again, I won’t know for sure until I get my mirror over there. In the meantime, any additional tests or checks you folks can offer will be greatly appreciated.

Regards.
 

buzzbombtom

captin sleep0
Registered VIP
Registered OG
5+ Year Member
10+ Year Member
head gasket... LA is HOT AS BALLS right now... check your hoses, heater core hose could be shot.
 


MetroShop_2000

New Member
Ok folks, I've done some testing...

Thermostat wasn't opening properly so I ordered a replacement. In the meantime, here's what else I came up with...

- Exhaust gas block test came back clean
- Radiator pressure test came back good
- Compression was 125 in all cylinders
- Flushed heater core
- Spark plugs were good with normal wear, no sign of coolant in cylinders
- Performed pressure test by using a compression fitting in each cylinder at TDC and putting 110psi air into each cylinder while other cylinders still had plug in place. No bubbles came out from the radiator neck but the coolant level did rise very slowly with each cylinder pressurized

I'm confident the overheating will be solved with the new thermostat.

Does the above confirm the head gasket is good? Did I perform the last test properly?

Thanks in advance...
 


Restotech

Respected
If what your saying is accurate, you have a leaking head gasket. The coolant should not be affected at all by pressurizing the cylinders.
 

Restotech

Respected
Seen cylinders Hydra lock from coolant and still have no water in the oil. That means nothing. You don't always see smoke either. Small amounts won't be seen. You need to test for combustion gasses in the coolant. There is a special fluid and tool that looks like a turkey baster to do just that.
 

MetroShop_2000

New Member
I tested for combustion gases with a block tester I rented from Auto Zone. Tested clean. That's what's worrying me...

No obvious liquid in oil, no obvious signs of coolant in the chambers, combustion gases test is clean, no more overheating. Only thing is when pressurising the cylinder, the coolant level rose in the radiator (but no bubbles).
 

bajalou

New Member
I went thru that with my 01 LX, so i replaced my temp.coolant sensor ,its job is to send a signal that turns on the two cooling fans you hear that cycle when your coolant temp. reaches a set temp. diagnosing the overheating issues i also replaced thermostat. problem solved!
 


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