Well, yesterday I just needed to drive a short distance from home and even though I needed some gas I decided to keep driving, I was very tired and did'nt feel like stopping. The fuel guage was almost in the red when I got to where I was going,and when I was leaving the car had trouble starting. This was about 9am on a hot saturday. I got home and slept for a while. I did'nt start it up again until about 7pm, and again it would barely start and now the temperature had gone all the way up to the red. I finally got the car to start and headed directly to the gas station, filled it up and proceeded to drive two cities away. The temperature gauge was all the way up the whole time, I thought it might go down after driving for awhile, but it did'nt, and I could feel that it wasn't at full power when I accelerated. I did make it home though saturday evening. Tonight sunday, I waited all day til the weather cooled down to try again, started up OK, but again temperature guage went all the way up immediatly. I test drove it to the gas station, still low power. Filled it up, proceeded to drive home. Checked under the hood when I got home and it was very hot in there, I could feel it on my face. I just had a new radiator installed 2 weeks ago. Any Ideas why the temp is so high?
temperature gauge is all the way up 86 240
Aug 01, 2005
8 Replies
bad radiator air lock in coolant normal temp, bad temperature stabilizer board gadget slipping fan clutch pick one
Who put in the new radiator? Perhaps a hose was not made fast? Is there fluid in there?
"Steve" wrote in news:jdWdnYb9 snipped-for-privacy@comcast.com:
A well respected volvo shop installed the radiator, and yes there is fluid. I called the shop today and the guy said it sounds like an electrical problem. Possibly a bad temp sensor.
Thermostat bellows sticking closed?
Since the temperature gauge is all the way up, even when the engine has been sitting overnight, there's no doubt you have a wiring or gauge problem. By the way, ignoring warnings like a high temp gauge is a good way to ruin an engine quickly. Fortunately for you, the gauge reading appears to be wrong, but if it had been correct, you'd be looking for a new engine now.
Also, "trouble starting"; wouldn't crank, or wouldn't fire?
There's a little printed circuit board on the back of the instrument cluster that provides bias to the temperature sensor and linearizes the result. The board plugs into an edge connector and is trivial to swap out once you have the cluster in your lap.
When it went bad on my '87 240 (pegged at zero) I replaced it with a new board from Volvo for about $150 and that fixed it.
The board only has one component on it, an LM324 op-amp, which is a very common single-supply utility op-amp. When the board went bad on my '89 240 (railed high), I replaced the op-amp for about $1 from Radio Shack and that fixed it.
Of course, if the engine has real overheating problems, it isn't the PCB on the sensor, but it did eventually go bad on both of my late 80's 240's
-RL
uhh...maybe lack of coolant?...
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