2001 lincoln LS V8 P1299 and misfire

[fankbru]

my cars been recently overheating and shaking.... When i did a diagnostics test i got code 1299... Found out my 4th cylinder is misfiring.. I am going to replace my thermostat and hope for the best.. also going to replace my spark plugs and coils.. Where is the 4th cylinder located?

[shorod]

Welcome to the forum!

The P1299 code is for Cylinder Head Over Temperature Protection Active. According to the factory service manual, this code indicates that the CHT overheat system was activated, likely due to one of the following concerns:

• Engine cooling system concerns
• Low engine coolant level
• Base engine concerns

So, if you didn't have a P0304 code as well, what lead you to determine cylinder #4 has a misfire?

Standing in front of the car with the hood open, looking at the engine, the cylinders are numbered sequentially starting with one on your left side (Bank 1) nearest the belt. Since you originally posted this on a thread for the V8, I'll assume you have the V8 as well. Cylinder #4 would be the rear left cylinder (nearest the firewall). Cylinder #5 would then be on the right side of the engine (Bank 2) nearest the belt, etc.

-Rod

[fankbru]

hey shorod.. after doing the diagnostic test we were able to determine that my 4th cylinder was misfiring the code did pop up... Which i sort of knew because my car was bucking and shaking and misfiring constantly.. likewise my car is a v8 as you assumed. the test was able to tell me which cylinder was actually misfiring the 4th cylinder... tried replacing my thermosta today and found myself ridiculously aggravated.. I didnt have the right tools to extend to the bolts on the thermostat nor could i remove the tube thats above the thermostat mount... in the process i dropped one of my tools which was then eaten by the car because i could not find it. I have never been able to not replace a thermostat on a car in my life!! to save me the aggravation A buddy of mine thats a ford tech is going to do this work for me... after i do the thermostat im then going to take a look at whats going on with the misfiring.. if its the spark plugs do you reccomend that i just replace all the plugs??? i appreciate the help

[shorod]

I suspect that you'll find the problem to be oil on a coil rather than just a spark plug. Leaking spark plug well seals are a pretty common issue on the 2000-2002 LS's. Since that coil is near the firewall, it could be moisture due to the location of the cowl and possible lack of sealant on the coil covers, but that would be very intermittant as the heat of the head would boil off the water after driving post-rain or car washes. If you find oil on the coil(s), you will want to consider replacing the valve cover gaskets and at least that particular coil. You may find replacing the valve cover gaskets on the V8 to be easier than the thermostat.

-Rod