My temp guage will fluctuate at times, bouncing mostly from normal temp to zero or in that inbetween zone. There is rapid fluctuations, slamming to zero for awhile and back up.


At a similar time, I ran low on coolent due to a slow leak in my radiator, finally was able to pin the leak on the plastic to metal interface, put a new one in before the engin blew....I think.

The guage does it more often....If the block were boiling inside, the temp would not go lower, right.....Whouldn't it go higher if the coolent were boiling inside.....

So I think, the fluctuations when the raditor was spilling it's guts was a coicidence? I'm a bit gun shy on this, But

The radiator keeps pressure for long periods (last night after 20 hours it still had good pressure in the system)

No coolent lose presently since the rad was changed

A NAPA head gasket leak tester fluid kit was used to check the head space of the radiator bottle after climbiming a large hill (600 foot) and it came back negative (test recommended in FAQ)

So is it the grounds in my instrument panel that are causing the issue (the speedo was psycho last spring, bouncing around and going to 70 mph while I'm doing 30 etc).

So I'm planning in digging into the panel and redoing the grounds, Is that a ligit direction, I don't want to blow the engine after 199,980 miles, almost there to 200k.

Eric
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1990 745 258k Rex, 1991 745 160k Bosch, (RIP 89 745 250k)