97 D1, 208K+ miles...
OK, so where do I begin...I guess the best way is to let everyone know that coolant-related issues have been dogging me for, well, probably the last 50-60K miles. Radiators, Manifold gaskets, head gaskets, sensors, clutch fans, electric fans, heater cores, you name it...and on and on.
During one of the attempts at resolving my coolant-related issues, it was identified that the temp. gauge in the instrument cluster no longer had the proper impedence (resistance). The shop installed an inline resistor about equal to the gauge's spec and all seemed well for the past several months until recently. I had a head gasket replaced and am still having some coolant dripping issues (see related threat Intermittent Coolant Leak). My temp. gauge has been acting very strange lately. It usually seems to be fine, pinned around the 40% mark. It used to be at 45% before the new resistor trick. I think the replacement resistor is a bit higher, therefore I probably get less needle movement upwards. When driving the car for a while 30-40 minutes, when I am cruising on the highway on cold days, the gauge seems to move downward a bit. OK, seems reasonable, right! But even more lately, when I am just driving on regular roads, when I hit the throttle a bit, the gauge completely drops to the bottom, and as soon as I release, it begins moving upward. I don't know the exact RPM, but it only seems to occur after driving for a bit. I have not figured out the details as of yet. Perhaps related to my coolant leak -- who knows. It has been too cold to work under the hood lately. I have terrible luck manipulating small plastic and metal parts in cold weather -- can you say $#@!, I knew that was going to snap.
UPDATE: It does not seem to have anything to do with RPM, because when the problem begins, if I stop the car, place it in Neutral, and rev the engine, there is no problem. Also, I have noticed on a few occasions, that even descending a hill will cause the gauge to drop.
I can tolerate a broken gauge that fails consistently, but how do you explain erratic readings?
Any ideas?
OK, so where do I begin...I guess the best way is to let everyone know that coolant-related issues have been dogging me for, well, probably the last 50-60K miles. Radiators, Manifold gaskets, head gaskets, sensors, clutch fans, electric fans, heater cores, you name it...and on and on.
During one of the attempts at resolving my coolant-related issues, it was identified that the temp. gauge in the instrument cluster no longer had the proper impedence (resistance). The shop installed an inline resistor about equal to the gauge's spec and all seemed well for the past several months until recently. I had a head gasket replaced and am still having some coolant dripping issues (see related threat Intermittent Coolant Leak). My temp. gauge has been acting very strange lately. It usually seems to be fine, pinned around the 40% mark. It used to be at 45% before the new resistor trick. I think the replacement resistor is a bit higher, therefore I probably get less needle movement upwards. When driving the car for a while 30-40 minutes, when I am cruising on the highway on cold days, the gauge seems to move downward a bit. OK, seems reasonable, right! But even more lately, when I am just driving on regular roads, when I hit the throttle a bit, the gauge completely drops to the bottom, and as soon as I release, it begins moving upward. I don't know the exact RPM, but it only seems to occur after driving for a bit. I have not figured out the details as of yet. Perhaps related to my coolant leak -- who knows. It has been too cold to work under the hood lately. I have terrible luck manipulating small plastic and metal parts in cold weather -- can you say $#@!, I knew that was going to snap.
UPDATE: It does not seem to have anything to do with RPM, because when the problem begins, if I stop the car, place it in Neutral, and rev the engine, there is no problem. Also, I have noticed on a few occasions, that even descending a hill will cause the gauge to drop.
I can tolerate a broken gauge that fails consistently, but how do you explain erratic readings?
Any ideas?
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