cold weather = serious loss of power

[cts1]

Hello TDR brothers,

A bit of a lengthy explaination here, so please bear with me. '04 2500, 4WD, 35" Toyo M'T's, 77K, fluids, filters, faithfully changed @ 3-4K invervals. The problem occurs in temps below 32deg, the issue is can't-get-out-of-its-own-way power loss (unable to pull a 6% grade @ anything over 40MPH). EGT's are near 1500deg (normally 500-800deg), boost is maxed @ 23-26PSI (normally 30-32PSI). The symptoms usually clear up within 50 miles or when the ambient temp reaches 50deg or above. Mods or attempted fixes: BD silicone hoses (meticulously fitted/tightened), 4" Cone Engineering stainless muffler w/ tip, Westach combo boost/EGT on SRT A-pillar otherwise completely stock. Replaced MAP sensor, no joy. No codes, no smoke, no consistent power loss issues in warmer temps (I live in northern AZ), dealer has been unable to remedy the problem (in 3 tries). All fuel is purchased from busy locations and I've tried a variety of stations to eliminate bad fuel. The worst situation was driving a 2 lane, twisty, steep mountain road, under 25MPH, 20deg temp, had to pull over since it couldn't make enough power to travel 15MPH. Pulled over, shut down, restart, rev to clear the loaded-up fuel and was able to continue.

Thanks for listening, I'm trying to get this issue settled before next winter, any help is really appreciated!

 

[Missouri Mule]

Could it be a trans problem?

Can't think of anything that helps run engine that is cold sensitive. Dealer should have a remote computer(don't remember the name of it) that they can hookup that will collect data while you drive.

 

[cerberusiam]

I would replace the APPS, sounds suspiciously like problems that have been solved by doing that.



If you can shut it off, start it up, clear the engine and it runs correctly almost sure its electronic and the APPS is high on the suspect list.



The only other thing that could be influencing things is the ambient air temp and barometric sensor on the air box. Even unhooked don't normally see that kind of reponse though.

 

[Bill Weber]

Can't be of any help, but, I have had a kinda-sorta similar problem. Since I have a rail press gauge I have seen low press when the temps are in the low 30's. 6-8K at hwy speeds. The press DPOPS when I accelerate. When air temps get back to near 50F all goes back to normal. But, I have noticed no lack of performance. I recently removed the stock fuel lift pump and installed a spacer to allow the fuel to flow through the fuel heater. No help. Don't know that the heater is working or if it makes a difference.

How's that for a lack of help. Just food for thought.



Bill

 

[jelag]

My thought is the fuel heater in base of the fuel filter... . I'm sure its turned on by the ECM and I'm guessing that the heating element is not working... A few degrees change in fuel temperature makes a difference when you drop below 32*... ... could you have a drop or two of water that is turning to ice as well??

 

[Missouri Mule]

I was thinking the fuel was gelling a little.

I had an 88 ford van 7. 5L (460 c. u. ) that ran good until I hit a small hill on the highway then it wouldn't want to run ( no quages just idiot lights) it would finally clear up and I would be up to normal power. One garage thought it was the cat another place I stopped at said it was the computer. I found out if I pulled over and revved the engine it cleared up but blew a lot of black smoke out the exhaust when it did.

Took it to the ford dealer they did a hit miss at one time, they replaced the cat, the computer and something else to the tune of $1200 it never did it again but I retired the van the next year(because it stalled out on the highway with a load of produce on it, I also had the Mule for backup).

 

[JHMiller]

Boy your having some serious temps there for not going anywhere! From what you've said I would try and positively rule out fuel first. If they do not go to winter fuel (blended) each year and where your at I suspect perhaps not, then add Wally world 2 cy oil each tank. You should be doing that anyway each tank. 16-19 oz per 25-27 gal for a 555. Snow machines don't freeze up here in Wy @ -25 and neither does my truck fuel.

Verify that the fuel heater is working, very important device, in fact this is what I would do first.

Your traveling into temps that will gel straight #2 untreated fuel. If your fuel is not blended, then the nx time you plan a trip up high add a little #1 to your tank and blend some yourself, increasing the 2cy oil for lubrication. I've used higher oil ratios with no issues. Actually I noticed improvements in performance, mileage and smoothness and it's inexpensive and the lubrication I need so for me it's the stuff.

Ok, that all said, here's how to find out for sure if it's gelling. Get an extra filter, nx time pull over and pull the fuel filter, you'll know, good luck... . John

 

[cerberusiam]

The symptoms usually clear up within 50 miles or when the ambient temp reaches 50deg or above.



The worst situation was driving a 2 lane, twisty, steep mountain road, under 25MPH, 20deg temp, had to pull over since it couldn't make enough power to travel 15MPH. Pulled over, shut down, restart, rev to clear the loaded-up fuel and was able to continue.

If the fuel is gelling, fuel heater not working, its not going to clear itself up after warming up or shutting down the engine then restarting.



The fuel is not going to gell in the 30's or even 40's. Fuel heater will not impact the the engine operation this way.





If nothing electronic is found to be wrong, coud be simply the screen in the fuel tank is waxed up and plugging wheni t is cold or sucking enoguh garbage against the screen that a restart will drop it off. As the engine warms the tank return fuel is warmig existing fuel enough to stop the screen from plugging.

 

[cts1]

Thanks for thr insight. Would Marvel Mystery oil serve as an equivalent to the 2 cylinder oil you mention?

 

[cerberusiam]

Thanks for thr insight. Would Marvel Mystery oil serve as an equivalent to the 2 cylinder oil you mention?

No, MMO has a stoddard solvent base. It is a cleaner not a lubricator. It works pretty well to make sure the system is cleaned out and helps minmize carboning on the tips but only in regulated doses. I uses it every 4th mix I make up with Power Service when I am doing a lot of DD. The bulk of the time its 2 stroke and PS as an additive package.

 

[Yo Hoot]

FWIW

stoddard solvent = mineral spirits

 

[AH64ID]

I do not think that your issues are fuel related (gelling, plugged filter or otherwise), it takes fuel to get to 1500* EGT's. . When my fuel gelled it would stumble and there were no EGT's, boost, or smoke...

I am guessing its a sensor, you said you replaced MAP, what about the IAT sensor? Is the coolant at normal operating temp?

 

[CoastyAV8R]

I agree with AH64ID, you wouldn't be getting that high of EGT and boost if it were fuel starved. How cold is it where you live? Diesel fuel right from the pump with no additional additives doesn't gel until the low 20's at the earliest from my own experiences. I would have guessed transmission slipping if you are at 1500 degrees and 25 psi of boost but it wouldn't start hooking up when the temp went up. The APPS and FCA both can do weird things when they die though. TWest has a few sensors he lets folks try out to see if they can fix a problem, maybe give him a shout.

 

[fkovalski]

Thanks for thr insight. Would Marvel Mystery oil serve as an equivalent to the 2 cylinder oil you mention?

I live at 9,300 feet and can regularly see temps of -20 to -10 for several days many times during the winter. I use a good recommended diesel additive like Stanadyne



I use the "Performance Formula. "