‘03 Ford E-450 limp mode

[A32Deuce]

X2! I always go for the cheapest first.

[LarryH1481]

Originally Posted by THenne1713

Originally Posted by midasman

Be aware that ALL the Ford gauges except gas gauge are DUMMIES (from my 2002 Excursion 7.3 to my 2018/9 E450 V-10)!!! SHAME ON FORD!!! My Scan Gauge shows all except oil pressure (note oil pressure gauge NEVER moves--should be lower when HOT, higher when COLD).

Please

[twinboat]

My V10 thermostat fell apart and caused temp swings between 188 and 208 degrees, on a level road

Ford uses a by-pass thermostat and the by-pass valve part came partially off so the T stat wasn't opening the by-pass port.

Cheap and simple replacement. No gasket anymore, just 2 bolts and an O ring.

Big bet it isn't the water pump. They leak and rattle when bad. The impeller falling off or wearing down is a 100 million to one shot.

Has anyone actually seen this happen in the last 75 years ?

[PIGRIG]

My mechanic ran the die test for the head gasket - the blue die turned yellow. He is pretty sure it’s a blown head gasket. Lots of pressure in the hose coming from the radiator. I’m getting a second opinion but all signs lead to it. It’s the worst thing that could happen to me right now.

[A32Deuce]

Originally Posted by twinboat

My V10 thermostat fell apart and caused temp swings between 188 and 208 degrees, on a level road

Ford uses a by-pass thermostat and the by-pass valve part came partially off so the T stat wasn't opening the by-pass port.

Cheap and simple replacement. No gasket anymore, just 2 bolts and an O ring.

Big bet it isn't the water pump. They leak and rattle when bad. The impeller falling off or wearing down is a 100 million to one shot.

Has anyone actually seen this happen in the last 75 years ?

Yes! Cheap China imports!

[avfordguy]

Originally Posted by PIGRIG

My mechanic ran the die test for the head gasket - the blue die turned yellow. He is pretty sure it’s a blown head gasket. Lots of pressure in the hose coming from the radiator. I’m getting a second opinion but all signs lead to it. It’s the worst thing that could happen to me right now.

Head gasket issues are rare on the v10, not saying what PO did to it.

[Peat]

I have the 03 Ford V10 in my minnie and have had similar problems. The first problem was a false overheat signal being generated because the #3 coil on plug was weak and pulling to much power. The line that feeds the coils runs by the top overheat sensor and it was set off by the increased power. The Ford tech moved the wire away from the sensor and the problem went away. Also replaced the #3 coil.
While they had the minnie in the shop, I had them go ahead and replace the thermostat while they were working in that area. After that I started blowing coolant out the coolant recovery container. I ruled out the thermostat as the problem since it was new and it was installed by the Ford Truck dealer. After dealing with the problem for a while I decided to buy a new thermostat and replace it myself. Turns out the Ford Truck dealer put in the wrong thermostat. It had a long throw and wouldn't let the thermostat to fully open. Since I put in the correct thermostat with a shorter throw I haven't had any problems.
Good luck. Pete

[PIGRIG]

Originally Posted by Peat

I have the 03 Ford V10 in my minnie and have had similar problems. The first problem was a false overheat signal being generated because the #3 coil on plug was weak and pulling to much power. The line that feeds the coils runs by the top overheat sensor and it was set off by the increased power. The Ford tech moved the wire away from the sensor and the problem went away. Also replaced the #3 coil.
While they had the minnie in the shop, I had them go ahead and replace the thermostat while they were working in that area. After that I started blowing coolant out the coolant recovery container. I ruled out the thermostat as the problem since it was new and it was installed by the Ford Truck dealer. After dealing with the problem for a while I decided to buy a new thermostat and replace it myself. Turns out the Ford Truck dealer put in the wrong thermostat. It had a long throw and wouldn't let the thermostat to fully open. Since I put in the correct thermostat with a shorter throw I haven't had any problems.
Good luck. Pete

Thanks, Pete. What do you mean by coil?

[PIGRIG]

Update:

It was the fan clutch. Replaced it, all good! No idea why it cropped up just when I picked it up from the mechanic who did a tune up, but the theory is that there was air in the coolant system which caused the initial overheat/limp mode and was the final straw for the fan clutch. Either that, or it was purely coincidental.

[A32Deuce]

Each cylinder has its own ignition coil rather than one going to a distributor. No more distributors, now coil on plug. Computer now fires the plug.

Originally Posted by PIGRIG

Thanks, Pete. What do you mean by coil?

[Big Bear Local]

Originally Posted by PIGRIG

Update:

It was the fan clutch. Replaced it, all good! No idea why it cropped up just when I picked it up from the mechanic who did a tune up, but the theory is that there was air in the coolant system which caused the initial overheat/limp mode and was the final straw for the fan clutch. Either that, or it was purely coincidental.

Much better than a head gasket. Glad you figured it out.

[PIGRIG]

I just wanted to put another update out there. I posted about this issue in a few different threads, so I’m going back to each one to update everyone. Initially I thought the fan clutch solved the problem because I had one good test drive where the temps stayed around 217 consistently. The RV sat for another 2 months while I worked on some remodeling in preparation for full time RV’ing. I took it for another test drive and the issue cropped up again! Needless to say, I was frustrated. Someone my dad knows to be a guru at problem solving insisted I replace the thermostat which had already been replaced twice. I didn’t believe it would work, but I was desperate, and he was adamant. The issue was still there, so he advised to take out the thermostat. Since we believed you needed at least the hat to make a proper seal, we cut the thermostat off of the hat and just put the hat back in with the gasket. The temperatures were not fluctuating anymore, and the problem was solved! I was then advised to use the Ford OEM thermostat in there. I didn’t feel it would make a difference, but it TOTALLY solved the problem. O’Reilly’s, Advanced, and NAPA all sold me the same thermostat that sticks or doesn’t open at the proper temps. The Ford one gives me a steady 192 plus or minus a few degrees! I hope this helps someone!!!

Guy at Ford says the Knock off parts are designed to open within a range of temps, and the Ford one is designed to open at exactly 192. That was his explanation, but whatever the case, problem SOLVED.

[avfordguy]

Also has to due with the spring ford engines pump ALOT of water I have seen this where pump pressure overcomes the spring

[PIGRIG]

Originally Posted by avfordguy

Also has to due with the spring ford engines pump ALOT of water I have seen this where pump pressure overcomes the spring

I assumed, but this is good to know. I was scratching my head at how the differences actually made a difference.