Can't fix E350

[bryan]

HI
Has anyone ever had this problem with thier E350?After about 30 miles the speedo needle drops then when you let off throttle it comes right back up.After about 100 miles of this the waterpump starts leaking.It is building up pressure inside the coolant system but when Ford pressure tested the system it checks out fine.Has actually sheared the waterpump pulley off once.
1)The tranny trys to down shift into 2cd gear at 70 mph and stalls engine.
2)Put it in park and speedo needle will jump between 0mph and 5mph.
3)computer scanner shows actual speed when speedo jumps but the volts to ecm bounces between 6 and 7 volts.

This has stumped 3 Ford dealerships 2 Ford master techs and the tranny rebuilder.They have rebuilt the tranny,replaced the altenator, the instrument cluster and the speed sensor in rear end.One Ford tech wants to pull the rear end apart to replace stator ring.The tranny shop says its in the wiring or the ecm and has sent it to a larger Ford Dealer for more diagnosis(SP).

I remember having simalar problems with a 94 E350 and spending tons of money on it and then an old Roberts driver told me to ground tranny and that fixed everything .Then in 2001 Ford couldn't fix my windshield wiper problem (they wouldn't shut off) and a guy told me to pull the plastic cap off of wiper motor and clean the contacts.

 

[randy123]

the ecm will only take .5 mv......if its reading 6 to 7 you have a short some where....most likly its pin 60 in the ecm.. have the tec do a key on and key off and see if the volts change pin 60 is the ground for the ecm... its touching a power wire in the harness somewhere...and i would say its the trans harness because of the trans and spedo problems.... randy

 

[davekc]

It sounds like two different issues. The waterpump issue is seperate from the transmission unless it is over heating or there is blockage in the transmission coolant line. If so, that would only affect the shifting, not the speedometer. I am refering to the shift selenoid.
Ford had numerous service bullitins on transmissions with moisture entering the electronic shift module. Both listed items are not considered part of a transmission rebuild. I agree with Randy that on the ECM test, this may or may not show up.
Heat and moisture make it a difficlt repair to diagnose
I would replace electronic shift module and electric harness to ECM for this part.
Let use know how it goes







Davekc
owner
21 years
PantherII
EO moderator

 

[greg334]

Really dumb question; where is the ECM located? GM put the gas ECM under the left side under the hood. What happens is that water and washer solution drips down onto the ECM and corrodes the connectors. The weird things that happen when it starts to short out the ECM, wow. Fortunately the diesel is located under the dash.

 

[davekc]

ECM on most Fords is under the hood. Not sure on the vans? Most of the corrosion, heat and moisture issues are at the module or connections. This is located on the side of the transmission. Our county maintenance mechanic has replaced all of them on Ford police cars over two years of age. Same module is used on the vans.




Davekc
owner
21 years
PantherII
EO moderator

 

[randy123]

the 5.4 and the 4.6 water pumps have a problem...i have been a master cert tech for 13 years and i changed at least 50 water pumps on ford vans...hardly ever any chevys or gmc...its the belt that kills the pumps...it side loads the bushing on the water pump and it will leak only when running...shut the van off and it will stop.. so pressure checking the system will show normal...also some times the intake will crack right at the bottom and leak..(only when hot) i have changed many intakes on the trucks and a few vans...


one of the land star drivers just got a new van and the pump went at 15,000 miles...at 22.000 the ac pump went...as to the trans.. the speed sensor is a magnetic pick up if the fluid has small pieces of metal in it it will mess up the calabration and that will fight the ecm...the ecm will read throttle being applied and the speed sensor will read no movement or slow movement... when the van sits over night the metal in the lube will fall to the bottom...when you drive it it will warm up and the lube will thin out and start to move the metal that has settled at the bottom... the best thing to do is let it sit over night and pull the diff cover and run a magnet along the bottom of the case...if their is metal, the most likley cause of this will be the wheel bearings... you can also pull the speed sensor and see if it has metal on the end...

 

[highway star]

Waterpumps are definately an issue on the 7.3. The one I have now has been on there since 2/04 and is the best one I've had, ever.

 

[bryan]

HI
The problem was one of the engine's wiring harnesses was laying on the altenator.They said the sensor wires were picking up interference from the altenator.Thus sending the wrong signals to the computor.So they wire tied it to the dipstick and now it fine.3 months, $4800.00 in repair bills and about $12,000.00 of lost income.One wire tie priceless.Good Luck and Have A Happy Easter