4.9 inline six temp gauge fluctuation
cavf150
02-11-2005, 09:40 PM
Hey,
Can anyone give me advice on why my temp gauge has gone on the fritz? At start up all is fine , 5 miles down the road the gauge rises to the O in the gauge then suddenly goes back to normal. Then it climbs slowly again then back to normal. Fluid level is at the top and shows no leaks. The oil is w/o freeze in it and is at full. Can a bad cap cause this, or a sender unit? Where is the sender unit located on the engine? Engine has a/c. Too cold here to turn it on. Heater throws hot air and the top rad hose is hot. Could a air lock have developed somehow? Engine is not overheating!
Thanks,
Can anyone give me advice on why my temp gauge has gone on the fritz? At start up all is fine , 5 miles down the road the gauge rises to the O in the gauge then suddenly goes back to normal. Then it climbs slowly again then back to normal. Fluid level is at the top and shows no leaks. The oil is w/o freeze in it and is at full. Can a bad cap cause this, or a sender unit? Where is the sender unit located on the engine? Engine has a/c. Too cold here to turn it on. Heater throws hot air and the top rad hose is hot. Could a air lock have developed somehow? Engine is not overheating!
Thanks,
andy2005
02-12-2005, 07:23 PM
I have heard that after 1988 Ford gauges are basically a light with a needle hooked to it. My guess would be that it everything elese seems fine, its probably a sending unit.
mustangmike351c
02-12-2005, 09:09 PM
check your thermostat it may be sticking
ModMech
02-12-2005, 09:10 PM
The temp gauge is a real gauge, I suspect either the thermostat is sticking, or the sender is bad. Since you need to drain the coolant some anyway, I would replace both with FACTORY replacement (Motorcraft) parts.
cavf150
02-13-2005, 09:48 AM
I have heard that after 1988 Ford gauges are basically a light with a needle hooked to it. My guess would be that it everything elese seems fine, its probably a sending unit.
ANDY,
Thanks for the input, I am starting with the sender
cavf150
ANDY,
Thanks for the input, I am starting with the sender
cavf150
cavf150
02-13-2005, 09:50 AM
check your thermostat it may be sticking
Mike,
Sounds like it. does a thermostat constantly open and close?
cavf150
Mike,
Sounds like it. does a thermostat constantly open and close?
cavf150
cavf150
02-13-2005, 09:54 AM
The temp gauge is a real gauge, I suspect either the thermostat is sticking, or the sender is bad. Since you need to drain the coolant some anyway, I would replace both with FACTORY replacement (Motorcraft) parts.
ModMech,
Seems to be the consensus of all replies, I am changing the sender 1st
The thermostat change is pretty straight forward and I'll do it next.
cavf150
ModMech,
Seems to be the consensus of all replies, I am changing the sender 1st
The thermostat change is pretty straight forward and I'll do it next.
cavf150
J-Ri
02-14-2005, 04:33 PM
does a thermostat constantly open and close?
Not unless it gets cold coolant flowing by it. It will fluctuate a bit until the engine's been running for awhile.
Not unless it gets cold coolant flowing by it. It will fluctuate a bit until the engine's been running for awhile.
mustangmike351c
02-14-2005, 08:26 PM
Mike,
Sounds like it. does a thermostat constantly open and close?
cavf150
its should only open at the temp it is made for but if its sticking it will not open until it gets hot and then open util it cools back down and it may stick open and over cool making the temp go all the way up and back down many times
Sounds like it. does a thermostat constantly open and close?
cavf150
its should only open at the temp it is made for but if its sticking it will not open until it gets hot and then open util it cools back down and it may stick open and over cool making the temp go all the way up and back down many times
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