I have a 1999 Volvo XC70. She’s done really wonderful for me, taking me literally across the country and back. Now with 218,000 miles, we’re starting to have some problems.
The issues I’d like to tackle on this post is the overheating.
It’s tear-jerking and getting worse with the Austin summer, and I need it fixed very soon
This is a long post. If you want to just want a vid, this is 2 minutes:
(I forgot to mention the thermostat replacement. And I was corrected: the fan is not Volvo, just the shroud.)
When the temperature outside is over 70ºF, and I am in stop-and-go traffic, she overheats. Climbing hills and sitting at stop lights exasperates the problem. Using the A/C is basically not an option, as unless I’m traveling at highway speeds this will certainly cause an overheat as well.
The temperature gauge will slowly climb in stop-and-go traffic until the reservoir overflows.
Also, the fan ONLY RUNS AT HIGH SPEED. However, I am unsure if it tuns off at improper times.
In general though, this engine compartment gets HOT. Like, really hot. Today I went out to fiddle with it after two hours of sitting and it was like I had just turned off the engine.
1) Turning the heat on helps, but only to delay the eventual redline/overflow.
2) When the issues started, the reservoir cracked. I replaced it with two used ones and they also cracked. I put a new one in and it is still holding, but the overheating still occurs.
3) I have replaced the thermostat (However, I believe the one I took out was a 185ºF and I put in the “premium” 191ºF from AutoZone… I have been told the 6 degrees shouldn’t make a difference; I hope that’s accurate. Regardless, the issues persisted the same after the replacement).
4) My neighbor mechanic replaced the fan. I think he did this basically because he was out of ideas… The fan that he put on there is undersized. It is maybe a 10” aftermarket fan. I don’t think it ever needed a new fan. Regardless, the issue persists. And now I’m stuck determining if I need a new, properly sized OEM one.
5) I (partially) flushed the coolant system by taking off the drain plug at the bottom of the radiator (driver side) and spraying a hose into the reservoir. (Note: during the refill of the coolant, I dropped that little aluminum lining under the cap into the reservoir and it went into the system… this, like isn’t a real big deal right? Regardless, issue persists the same before as after). The radiator does not leak and looks to be in great shape.
6) One of the hoses was about to burst. It’s the large one near the right side (driver side) of the engine block. Replaced and holding strong. (This was replaced by an actual Volvo mechanic. I took it to him for the overheating issue. He replaced the hose, topped off my AT fluid, greased up my hood-pop lever, bundled the hack-job my neighbor mechanic did on my fan wiring, told me my fan was too small and that when he drove it with a thermometer under the hood, well, it was too hot. Then he gave it back to me, problem still there. He was just one of these solo Volvo guys with more business than he knew what to do with. I got the feeling he felt that to truly diagnose the problem he’d potentially have to spend two days taking apart the cooling system and just didn’t want to deal with it or my limited wallet.)
At this point, I have a few final solutions:
1) Replace the ECM ECU Computer (Ebay: $75). My computer seems to do weird things. Sometimes my Check Engine light or Brake light will come on, but not for long and the codes are always weird. And if it’s having trouble controlling the fan then that could definitely be it.
2) Replace the ECC Blower Motor Resistor Speed Module (Ebay: $40-$150). I found this video:
. My fan definitely only runs on high speed. So perhaps this is the problem? However, that would mean it should have trouble warming up, not cooling down… right..??
3) Replace the freaking fan (Ebay: $30-$440). Certainly, a larger fan will help. But again, this problem persisted before and after.
4) Fully flush the system. It’s my understanding that the flush I did was only partial, and that to fully do it I need to take some more things apart. Perhaps the system is gunked up? But, again, the problem really only happens in stop-and-go traffic. Even a constant 30 MPH is enough to cool the engine down.
5) Replace the thermostat again for a 185ºF.
Again guys, as far as engine compartments go, this one gets HOT.
Any other ideas? I’m really doing this baby a disservice because she’s such a beautiful ride and as my only driver on occasion do overheat her.
Not treating her right. Help!