Limp mode while towing...
 

Hey guys I have a 06 f350 with 196k miles that while towing a 7,000 lb camper through some mild hills all of the sudden power dropped down and a wrench light came on on the dash. I pulled over checked and restarted and it was fine again....then a little later it did the same thing. I'm scratching my head. Almost like the turbo quit. The dash still showed 20+ psi boost but it didn't feel it or sound like it.

My wife and I are camping with 3 kids and 2hrs from home. Any suggestions?

Thanks
Daniel

If you cant pull codes, check all boots on compressed air intake side to manifold for leaks, popped off boots. Also, any temp issues as these will put in limp mode if to hot, ie rad and water pump working, cooolant ,evel ect. Its also possible turbo sticking closed. Try an italian tune up, leafe the trailer and go for a hard rive, see if you can get boost to 27 psi. A couple hard pulls, accelerate hard wide open and then cool down and do again and again. Also, make sure fuel filters are good, no water in fuel, quality fool before the italian tune up. If the unison ring in turbo is sticking closed, explain low power low boost. If this fails, try an autoparts store to read codes thats close by.

Funny it did while pulling a hard hill. Pulling hard then not... Once I shut it off it worked fine. But no other cel. The temp showed normal on trans and engine.

I'll dog it tomorrow and see.

Daniel

Sounds like you have got > 15 degree spread between EOT and ECT, meaning you oil cooler is plugged. That puts the truck into limp mode, and is consistent with your story of this happening during a long uphill pull. Also consistent with returning to normal once you shut it down. You need to get some gauges ASAP.

The gauges on your truck are basically idiot lights with needles. All they show is cold/normal/hot. By the time they show "hot" it's probably too late. Do a little research and get your self a set of gauges. Scan Gauge II is a great little piece, no bells or whistles, that will tell you a TON of information about your truck for about $150.

or overboost.

Only way to tell with gauges? I wondered if it was over boost... Would a scan gauge show Turbo psi?

the dash gauge is accurate for boost . no need for a scangauge for that. I would be looking at delta temps.

I have a sct for my mustang would this work to read those temps? It has sat a logging.

I had the same problem. Light came on many times while pulling a trailer with the 4000 lbs camper on long pull uphill. My boost is at 28 PSI, the most I get. They changed the Map Sensor and no more Wrench light. Part is easy to replace, $49.00.
I will get a scangauge too. Does this gauge reads SCT

I have suddenly had the exact same issue while hauling my camper and towing my jeep. Funny that it happened sometime after turbo rebuild #3, but I can't tie it to that exactly as I don't haul like this but 2-3 times a year. Took it in after the first time, they replaced the exhaust back pressure sensor and another sensor, still same thing. 2 weeks ago they had to pull my engine to fix an oil leak, still same problem despite everything being removed and reinstalled. I'm in Moab, UT and driving back to SoCal Friday. What fun to have to drive half throttle for 900 miles and watch the boost gauge instead of the road, real safe. If it runs at mid 20's boost for more than 30 seconds or so, off goes the power, on goes the wrench light. This truck pulled fine for 4-1/2 years now this? Only 58k miles and 3 more payments, then warranty expires. Ford WILL fix this under warranty or we're going to have legal troubles, I won't accept any mystery issues/etc. This truck should give me 5 more years of service but with all the issues it's had, I won't own a Ford without a warranty. I'm becoming very unhappy with the dealers excuses on this truck. I also don't like having to make a 12 hour drive a 16 hour drive just because they can't/won't fix it.

I'll keep tabs on this thread, see if anything comes of it. Will be back at the dealer in a week to sit until they FIND the problem, or I take further action as necessary. I can't afford a new $55k truck with this one being pretty worthless if it won't run/pull as designed.

FYi it's a 2006 SDSC 4x4a, tires same dia as stock, turbo back Banks exhaust (been on it 3.5 years that's not the issue). All else is stock. 58k miles.

Thanks!

Did you check your MAP sensor, it is on the right side rear engine compartment. It could be your boost too. Mine was an underboost. The Map sensor was reading off a bit and sending a wrong signal. Do you have the codes, may be it is on your bill?

When I had the wrench light, I would shut off the engine and the limp more disapeared, until I boost over 20, a real piss off.

How does having a 15 deg spread throw it into limp mode?? I was getting readings of over 70 deg difference before I did mine and did it out of fear not because it blew.

The programming for the wrench light on ECT/EOT split is for 2005-2007 (I THINK it also included the 05's), and not the earlier model years.

Because the newest strategy VXCF9 is set to throw a CEL when your temp delta between ECT and EOT hit 15*. That throws it in "limp mode". Im not sure if its the same for '03s.