Community Forums

paulrlandon · 10-24-2018, 03:15 PM

Hey Guys! Have poked around here in these forums for a few years and finally have something I need assistance on.

I've got a 2012 Ford F53 chassis motorhome and have been experiencing ignition related problems for about 3000 miles. It all started on a return trip from Washington DC back to Washington state in August. As we were leaving DC (in a heavy downpour), the engine died/stalled while passing some vehicles. I was able to shift into neutral and restart the engine and then put back into drive and continue on. Thinking it was bad fuel, I stopped and put 4 bottles of SeaFoam in the tank. The problem persisted the rest of the trip and eventually got to the point where the engine would shut off at engine speeds above 3k. Posted the problem on JustAnswers when we got home and was told coils were bad and perhaps the alternator too (causing RF interference with Crank Position Sensor). Replaced all coils and plugs (Motorcraft for both) and the problem persisted. I did find the #2 spark plug had cracked near the bottom of the top portion of the insulator (just above the nut portion that is used to tighten plug).
I had some issues with the coil packs on installation and two of them didn't get properly seated onto the plugs. I stretched the inner spring and the mis-fires went away. During the diagnosing these mis-fires, it was suggested that I replace the throttle body and the accelerator pedal. So I did. Problem is still there. Have also replaced Alternator and Crank and Cam Position Sensors.
The motorhome runs great when just started for the first 10-15 minutes. Then WOT and even 3/4 throttle pulls where RPM's increase over 4k will kill the engine. Again, no warning lights, no CEL, No codes, and VERY repeatable. Have cleaned the MAF and replaced the air filter too. Any help you guys might have is GREATLY appreciated. Have been trying to get into a local Ford shop, but they don't seem to want to touch it. Thanks so much!

hawk57 · 10-24-2018, 03:45 PM

Do you lose all power when the engine dies - lights, radio, etc? If so check the ignition switch as it can fail, particularly if you have a large number of keys dangling from the ignition key.

okcnewbie · 10-24-2018, 03:50 PM

I would go here and start reading up on troubleshooting. It's not as bad as you think when you follow along with their guides.

Easyautodiagnostics.com than pick Ford and the closest size engine you can find.

Bahamaniac · 10-24-2018, 04:08 PM

Same issue last year. It ended up being the ecm computor.

ezdavie · 10-24-2018, 04:23 PM

Quote:

Originally Posted by okcnewbie

I would go here and start reading up on troubleshooting. It's not as bad as you think when you follow along with their guides.

Easyautodiagnostics.com than pick Ford and the closest size engine you can find.

Just had a similar problem (kind of). Pulling any incline engine would stutter and stall as batteries would drain completely. I originally also thought bad gas as we had been stopped and parked for almost 6 months. Couple if cans Sea Foam Mist and fill the tank. Problem still there. Truck shop diagnosed Bad alternator [emoji20] New alternator (110 amp) good for 400 miles. Next truck shop installed 145 amp alternator. Not ever sure that I found the cure - but - Two weeks now and running good [emoji106]

twinboat · 10-24-2018, 04:47 PM

Is your battery banging around in the compartment ?

Look for arcs where the positive cables sit. A short to ground, even for a second, could shut you down.

rjsupersonic · 10-24-2018, 04:50 PM

There have been issues with heavy rain and the air filter intake causing issues, don't recall where I saw it but..may have been YouTube, similar story guy was driving in heavy down pour and the engine died.

GPWayne · 10-24-2018, 05:41 PM

Have you looked at the air filter. The V-10 has a history of sucking water into the filter. Once wet it never works right. Must be replaced (paper filter)
The end fix is to install the FORD updated inlet J tube.

coachmanrvr · 10-24-2018, 06:06 PM

I had a 2013 Tiffin Allegro that had a similar problem and it too was reporting the crank position sensor. Ended up being the harness from the ecu to the crank position sensor. Took them 3 days of camping on the Ford lot in San Diego for the diagnosis. Only took an hour or two for the fix. They overlayed new wires for just the Crank Position Sensor.

I'd bet money that is your problem...good luck..

ThePowells · 10-24-2018, 06:37 PM

Welcome to the forum!

"007" · 10-24-2018, 06:57 PM

As has been mentioned water from heavy rains hitting the air filter and your MDF requires new filter in tube or filter box if it was a Workhorse chassis.
Many of us installed CAI CONE filters and the Fords had their mods to correct the problem which you may find info on in the Ford Forum.

Waiter21 · 10-25-2018, 05:18 AM

When it stalls, do the instrument panel lights and gauges still work?

Check fuel pressure. swap/replace the fuel pump relay.

In Pursuit · 10-25-2018, 07:21 AM

Following to hear what the final solution is...

paulrlandon · 10-25-2018, 10:18 AM

Wow! Thanks for all of the quick responses guys!! To answer the questions. some of the lights on dash come on when engine shuts down. I just changed the air filter and problem didn't go away. The NAPA Gold filter had the strangest black soot type material on it. Had no odor, but easily came off and discolored my fingers. It was semi circle shaped on the side of filter corresponding to the air intake shape. Tops of most of the pleats were also covered with it too. Regardless, changing filter didn't help. Only have 1 or two other keys on the ring and so I don't believe it's the keyed ignition.
It is a 2012 Tiffin Allegro QBA, so I'm thinking either the wiring harness for the Crank Position Sensor or the ECM is probably faulty based on the above comments. I'm leaning more towards ECM as when we connected the SnapOn scan tool to the OBD port, we watched crank position sensor and it's data looked fine. I'll do more reading and investigating and get back to you guys with what I plan to do. Thanks again for your quick assistance!