Overheating at stops/low speeds
#1
Overheating at stops/low speeds
It started doing this a week or so ago and figured it was the rad fan. I gave it a quick look and didn't seem to be coming on a few days ago.
Upon troubleshooting today, the fan is good, comes on with AC and when engine is hot, in fact upon running AC until 3/4 on temp gauge and turning it off, both fans kept running. Both thermal switches are good, one at coolant entrance & exit.
The first thing I tested was the fan, connected directly to the battery. Then I tested the 1st thermal switch I saw, in front of the head. I put a jumper wire in and started the car and the fan kicked on, I pulled the jumper, the fan went off and I plugged it back in at which point the engine idle was bouncing between 1k & 1.25k. Being a cool day I took it for a drive to heat up and idle went back to normal, but still experiencing overheating at stops/low speeds, and cooling down as I get moving. Although, I'm guessing, being such a cool day it wasn't getting as hot at stops, but also ran a bit hotter while moving.
I'm thinking the next step is the t'stat.
Also, as a side note, I have a minor coolant leak somewhere, I have to refill the overflow/reservoir every couple weeks or so.
Upon troubleshooting today, the fan is good, comes on with AC and when engine is hot, in fact upon running AC until 3/4 on temp gauge and turning it off, both fans kept running. Both thermal switches are good, one at coolant entrance & exit.
The first thing I tested was the fan, connected directly to the battery. Then I tested the 1st thermal switch I saw, in front of the head. I put a jumper wire in and started the car and the fan kicked on, I pulled the jumper, the fan went off and I plugged it back in at which point the engine idle was bouncing between 1k & 1.25k. Being a cool day I took it for a drive to heat up and idle went back to normal, but still experiencing overheating at stops/low speeds, and cooling down as I get moving. Although, I'm guessing, being such a cool day it wasn't getting as hot at stops, but also ran a bit hotter while moving.
I'm thinking the next step is the t'stat.
Also, as a side note, I have a minor coolant leak somewhere, I have to refill the overflow/reservoir every couple weeks or so.
#2
I'm sure someone more knowledgeable about Honda's will chime in here.
#3
I am pricing a t'stat now however, seemingly everything else is working properly.
#4
Does car overheat w/ AC on?
If not, the fans may not be coming on due to faulty thermoswitch A (on lower coolant return line beneath and behind distributer. It should close and enable fans at 194-205 F and if no fans overheating would occur at low/stop speeds.
If overheating occurring at speeds of 30 mph or more, then low coolant level and/or possible head gasket problem are possible.
good luck
If not, the fans may not be coming on due to faulty thermoswitch A (on lower coolant return line beneath and behind distributer. It should close and enable fans at 194-205 F and if no fans overheating would occur at low/stop speeds.
If overheating occurring at speeds of 30 mph or more, then low coolant level and/or possible head gasket problem are possible.
good luck
#5
For the life of me, I can't think if it heats up with AC on, but I can say both fans are running when the AC is on.
After driving around yesterday, temp seemed to randomly raise and drop, and running temp when it stayed even was midway on the gauge where typically it's a bit below midway.
Can I test the thermo switch?
If it's the head gasket, then there would have to be a puddle, contaminated oil, or low compression, yes?
After driving around yesterday, temp seemed to randomly raise and drop, and running temp when it stayed even was midway on the gauge where typically it's a bit below midway.
Can I test the thermo switch?
If it's the head gasket, then there would have to be a puddle, contaminated oil, or low compression, yes?
#6
So I went out for a drive this morning, AC doesn't seem to overheat or cool engine when on, and with AC off, and both fans running, doesn't cool engine, which don't turn on by themselves until well past the midway mark on gauge. So maybe thermoswitch A needs to be replaced. Also, I have noticed a faint coolant scent a couple times, and as well engine idle this AM was bouncing around from 1250 to 1500, then to 1000 to 1250 for the first 5 minutes or so of driving and then went to typical idle. The reservoir looks empty from filling yesterday, I'm going to let it cool down a bit and pop the cap off and start it up.
Last edited by Thorsteenster; 10-01-2016 at 07:53 AM.
#7
Just me but you are low on coolant and need to bleed the air from the cooling system.
Then find and repair the leak in the system.
Low coolant or air in the system will cause the issues you are having.
Then find and repair the leak in the system.
Low coolant or air in the system will cause the issues you are having.
#8
Yes, I'm thinking now it may just be a low coolant issue. I filled the reservoir yesterday and it's empty today along with the radiator being low. I filled the radiator and am about to drive again however, I'm not sure where it's leaking. The oil looks good, the exhaust seems to be fine, and I haven't noticed wet spots under the car, although it has been rainy the past couple days. I am definitely loosing AF somewhere though. It almost seems it could be a multiple point issue, or just the fact that ambient temp is approx 20 lower causing symptoms to act differently.
Last edited by Thorsteenster; 10-01-2016 at 08:37 AM.
#10
Check the carpet on the passenger side and along that side of the floor tunnel for wet spots. If it's not leaking in the engine bay, then it might be leaking into the cabin (heater core). It's gotta be going somewhere. You could even pull #2 or #3 spark plug and see if they're wet (gasket going between 2 cylinders).