I have a 97 F150 4.6l V8, 225k. I have been experiencing an overheating problem. I have replaced the radiator, hoses, water pump, temp sending unit, cylinder head temp sensor, t-stat, and fan clutch. I have also flushed out the heater core. I recently checked my ignition timing. It should fire at 8-10 degrees before top dead center but it appears to be firing at least 15 degrees before TDC. Could this be the culprit for my overheating problem?

 

I would say with the slack in the timing chains and the overheating issues you are ready for a rebuild .

 

Too much timing can cause overheating.
Are you running 87 octane fuel? If so - do you have any pinging?

 

I do have some pinging under a load or when quick acceleration. I am using super unleaded, 89 octane.

 

Is the truck actually overheating(Boiling water out the resevoir) or is it the temp gauge going in the red zone or both, If the truck is actually boiling over you could possibly have a leaking head gasket that is allowing a cylinder to pressurize the coolant sysyem, If it is only the temp gauge pinning then it could be an instrument cluster or wiring problem, You indicated you have already replaced temp sensors so these have been eliminated as factors.
How quickly does it heat up, Is it instantly or does it take a while, Are you losing coolant somewhere.

Run a pressure test on the coolant system and a compression test on the cylinders to rule out problems in these areas.

Val

 

89 Octane is mid grade (at least around here). But you should not have any pinging using 89 Octane. I would say your timing is off. Could be due to timing chain stretch. Definetly need to correct before something else tears up (like a messed up piston or valves). Plus running that lean is not good for the cat coverters either.

 

Timing chain strech that much will affect the fuel injection timing as well.
That is the job of the cam position sensor to tell the PCM when to inject fuel.
Also, the radiator could be plugged from it's bottom upward several inches but still allow coolant to flow but the total cooling capacity of the system is reduced from the loss of cooling area.
This usually shows up as 'ok' while running until you load the motor on a hill and/or shut it off, then it boils over while sitting with the motor off.
After awhile the coolant level gets so low it won't cool any longer unless running on the road with lots of air flowing.
Cooling flush on the truck usually won't clear a blockage this large.
One way to tell is if the radiator won't drain or drains very slow.
Timing test is usually done by looking at a position on the crank pulley then removing the link to see if the timing no longer moves because the PCM can't change it with the link open..
Testing the absolute timing is a tricky accomplishment with no real mark to go by except by a ''dial back' timing light..

 

[QUOTE=cmorningstar01;7889272]Is the truck actually overheating(Boiling water out the resevoir) or is it the temp gauge going in the red zone or both, If the truck is actually boiling over you could possibly have a leaking head gasket that is allowing a cylinder to pressurize the coolant sysyem, If it is only the temp gauge pinning then it could be an instrument cluster or wiring problem, You indicated you have already replaced temp sensors so these have been eliminated as factors.
How quickly does it heat up, Is it instantly or does it take a while, Are you losing coolant

I know this is an old thread, but my 2003 V8 4.6 f150 is currently experiencing overheating and stalling. I recently replaced my CHT sensor thinking this would solve the problem, it didn’t. I can drive my truck for about 10 minutes (while at operating temp around 205°F) then the temperature gauge will slowly begin ticking up until until the computer reads as hot. The only issue is that my engine doesn’t seem to actually be overheating (no coolant spews or loss and the system is holding pressure). If I put it in park it begins cooling off drastically, and if I turn the engine off and immediately back on the temp gauge is resting just above operating temperature (nowhere near where it was seconds before). I replaced the thermostat and drained my fluids to ensure a 50/50 ratio. Still no help, this is the first time I’ve been at a loss and nobody on this forum seems to have had this issue, can anybody offer any advice?