Is it in the same location as the photo above? In the coolant cross-over tube just a few inches from the t-stat housing? If so, my truck did not have one there. It was a plug that I removed and put in an aftermarket gauge sensor. If there is another sensor on the truck as the dealer claims then it is located elsewhere.

Btw, thanks for the help - looks like both the V8 and V10's have access to the CHT by removing only the alternator.

 

Was/is your gauges showing that you are overheating. how are you getting a false overheat? My gauge is doing as it should and when hooked up to a diagnostic tool it is in the proper ranges. I did the cht sensor but should I also do that second one.

At intial start up it is fine but once it warms up idle drops and is rough. multiple misfiring cylinders always 2 and 9 and if i let it idle to long it blows smoke out like crazy.

 

Factory gauge shows overheat issue. Aftermarket gauge shows nominal. I tend to believe the Auto Gage.

What happens is after I have run the truck for awhile, I will shut it off - say, to get gas. So after five minutes I get back in truck and fire it up. BAM - temp gauge is PEGGED! On several occasions it has gone into "limp mode" which is really my only concern. Can't pull a trailer full of quads uphill in "limp mode"!!!

Now, yes, I realize that since the engine is shut-off and coolant is not flowing that the temp will rise. However, the gauge which was showing nominal before I shut off the truck rises appx. 60-80 degrees in 5 minutes. The aftermarket gauge never even MOVES!!

I have had to shut-down and wait a few minutes - start it up and it runs fine. If it does NOT go into "limp mode" I just drive like normal and after 10-15 minutes the gauge will immediately drop to nominal - there is now "progressive" sweep - it goes from overheat to mid-range in about 2 seconds. There are absolutely no other signs that the truck is overheating - not causing it to run rough (any more than it is now, anyway - but even before I had the rough running issue) and I've never lost ANY coolant!

If I "pushed" the truck (drove it hard) before I changed all those cooling system items the aftermarket gauge would climb up to 190-210 range. Actually, I prefer that range but when I changed the t-stat I could only find 180-degree t-stat.

After changing all of those items the truck warmed up quicker and barely ever moves about the 180-190 degree range on the aftermarket needle.

Would like to find that other sensor and change it out to see if it helps with that. I do not believe the rough idle/run of the motor is connected to the false overheat (code 1285 - CHT). I thought they MIGHT be related when I read what FireFighter had on his truck. Since the CHT sensor didn't fix the issue, I suppose they COULD be related items, but I am back to thinking they are separate issues.

I read on here about some methods to "burp" the system as well and will try those - it's free and can't hurt at this point!

 

Just got back from Summit (in Tallmadge). Got eight (8) Motorcraft COP's for $39.95 each. Yes, they are 49.95 on the website but when I called to order them I found out they will price match.

So, I pointed the guy to DieselFiltersOnline where they are $43.95 BUT if you purchase eight they are only $39.95.

While doing a LOT of research as to which COP's to purchase guys had good and bad to say about every brand; cheap Ebays, Accels, MSDs, etc. I did not find ONE single complaint from anyone who put the OEM Motorcraft DG508's back in. I figure they got me over 100k, I'll use 'em again!!

I intend to put them in tomorrow so we'll see what kind of difference it makes.

 

Ok, guys, I finally put the new coil packs in last night. Had a buddy over to help and my son so probably spent as much time bs'ing as actual work!! Sure, #4 is tough and my 7mm socket is now a permanent part of my truck - somewhere lost in the abyss (never found it and it never fell out).

I stripped one of the bolt taps in the manifold but a tap cleaned it right up (M5 x .8 pitch in case anyone ever needs to know).

Truck runs AWESOME at this point!!! It still has a very small hesitation when "punching" the throttle. I have not been able to determine if it still has the false overheat but presume it does.

The last few weeks I have had an exhaust tick in the morning and it goes away after about 30 seconds. Now it's not going away so I have a leak in the right side exhaust manifold. I always said I wouldn't put headers on just to do so but when the manifolds went I'd throw some on. Starting to look for some now and found some Flow-Tech SS for under 400.

Again - no codes, but reader stated "multiple misfires" I had replaced one of them back when I did my plugs and I put it in #4 (hardest to get to). My son says "since that one is pretty new can we just leave it in?" I said "Well, I want to be sure when this is all done I don't have a doubt in my mind like 'is it the ONE we didn't change?'"

Once again a happy camper with how the truck is running. The other issues I can address later. For now I can simply leave the truck running for short stops to prevent it from going into the false overheat. If I leave it idling that doesn't happen.

Oh, and the screws for the TPS will NOT budge and are at such an awkward angle I am going to have to remove the throttle body to change it (I think that may be responsible for the slight hesitation at launch). At that point I may just change out the IAC as well (cleaned it before).