Hot start issue

[yourm0m1]

okay story goes like this.....few months ago i thought i ran out of gas one day gauge was low and idiot light came on before i parked at a grocery store. came outside within 5 minutes truck cranks but no start, decided it was fuel and go gas later in the evening and it started fine. weeks later does it again, figured out the driving conditions matter. if i drive for more than about 30 minutes and at least on the highway so 60mph+ then park it wont restart until about 30 mintues of being cooled down.....i am attaching a picture of the original issue that i thought was the solution some sensor not sure what it is maybe someone can point it out but there is 2 hoses connected the one to the right in the image had a large hole melted in it and the plastic loom covering the wires directly next to it being held by my finger had melted also, seems that the loom caused the hose to melt....well i replaced the hose and thought all was fixed, nope.....still happens

basically i get crank but not actual start, seems like fuel is being cut off. i can press the gas pedal and have no resistance, the truck sputters for a few seconds then dies. i am now thinking it is the ect sensor, i am concerned though about that loom of wires, it looks like the ect sensor wiring runs through that same loom so im wondering if the wires themselves are the issue and not the actual sensor.

no i have not tested fuel pressure but i do hear the fuel pump. temp gauge on the dash functions normally usually cool

sorry for the long post, just looking for info on that wire loom really and if the ect would cause my issues above

98' sport ohv btw

http://img339.imageshack.us/img339/7734/truckz.jpg

i have lurked here for years thanks for all the help guys, just did the 00m12 fix last weekend on my moms explorer and it was a piece of cake and solved 3 error codes and rough cold start

 

[gtyates]

Are the wires themselves actually melted or just the plastic surround?
As far as the hot start issue I had that as well. A new ECT sensor solved it for me. Mine had not gotten quite as bad as yours yet as I was still able to start it "hot" but it sputtered and ran rough until I hit the accelerator. If your gauge always reads cool you might want to replace the sending unit as well. Both the ECT and sending unit are just below the throttle body. Sending unit is on passenger side, ECT is on driver's side. Easy 10 minute fix. On my truck, since new, the gauge has never gotten above about 1/3 the way up and the sending unit was replaced twice.

 

[yourm0m1]

the wires themself are not exposed just the plastic loom is melted...i plan to check continuity later with a multimeter just to make sure....my theory is that the hose that melted had a reaction with the plastic loom one day at a certain temp but my whole hot start issue was occuring right around the same time period so i wonder if they are related thats all, i need to check the color of the wires on the sensor to see

the coolant gauge isnt "always" cold it does climb to almost the middle when im on the highway doing 70+ so i think it is fine, one thing though i noticed there is only 1 wire on that sensor is that normal? it operates so i figure its fine.

 

[gtyates]

The sending unit for the guage is 1 wire, the ECT is 2. As far as the melting issue, that hose next to the wires is coming off of the EGR line so it does get hot for sure!! The sensor where the 2 hoses conects is the DPFE (or EGR) sensor. Those go bad over time due to moisture build-up inside them. When it goes bad it sets a fault code for insufficient egr flow, P0401 IIRC.

 

[yourm0m1]

cool, thanks for all the info....since the ect is only $15 i plan to change it sunday...and get my engine bay cleaned up

 

[2000StreetRod]

DPFE hose & ECT sensor

Did you replace the hose to the DPFE sensor with the correct item (high temperature hose) or did you use fuel line or something similar? If you did not use high temperature hose then it will soon melt and then exhaust gas will flow out of it and melt the insulation on the nearby wiring. The hose is easier to replace by unscrewing the DPFE sensor rather than trying to bend the hose to fit.

The ECT sensor screws into a brass bushing in the plastic thermostat housing. The bushing can spin in the housing when you try to remove the sensor and then leak . I suggest that you apply something to remove surface corrosion at least a day before trying to remove it. The replacement housing is very expensive from Ford. Also, there should be a small compression O ring between the sensor and the brass bushing. Don't misplace it or forget to install it.

 

[yourm0m1]

i used hose from autozone that they sell by the foot....ill look closer and see what is was and look to see if they sell high temp hose, i didnt think about that thanks....

thank you for the tips on the ect sensor also! any suggestions on removing surface corrosion?? im guessing a can of coke like used on battery corrosion wont work??

 

[2000StreetRod]

Solvent

You might try P.B. Blaster, WD-40, or any type of penetrating liquid/rust solvent.

 

[ranger7ltr]

The ECT sensor screws into the intake manifold on the OHV...

Unless your ECT sensor is super corroded, you should not have any issue replacing it...Don't forget to use eithe liquid teflon or teflon tape on the threads so it doesn't leak...And I would recommend replacing both the ECT and the temperature gauge sending unit since you have to drain some of the coolant to replace one so replacing both kills 2 birds at the same time...

And if the lines either melt or blow off the DPFE sensor you might have a problem with exhaust flow being restricted...I have used regular vacuum line on mine for almost 18 months and it is still as flexible as the day I installed it...

Oh and on the no start... Have you changed the fuel filter yet? The behavoir sounds like the engine is starving for fuel under load...And I would test the fuel pressure too.. Just because the pump runs it doesn't mean enough fuel is getting to the injectors...30-45 psi is nominal...

 

[gtyates]

When I changed my ECT sensor it was very easy to remove actually and mine was original to the truck. The new one I bought came already covered with teflon tape on the threads. In my case it did solve the hot start problem. But my truck had been FULLY analyzed twice. Also my fuel pressure was perfect.

My only remaining concern for me is some tranny shudder I am not liking.

 

[yourm0m1]

well i thought i had it fixed by replacing that $15 part....went over a month with no issues. i just drove 1300 miles stopping for gas 5 times and never had an issue, then today i drove around town running errands stop and start 2 times. arrived home unloaded and 5 mins later would not stay on, basically same issue like someone said above it seems starved for fuel. back to the drawing board i guess.....

i dont have the tools to test fuel pressure so that will be a later test i guess....what about the dpfe, can that part get hot and cause the vehicle to not get fuel? how about maf or iac?

thanks for the input guys

p.s. the check engine light is not and has not been on in years since i replaced the 02 sensors

 

[yourm0m1]

well it looks like it was the fuel pump all along....it has kicked the bed now to where letting it cool down it wont start still....actually it is cranking constantly but not starting, i am also not hearing the pump turn on....i have swapped relays and checked fuses so i think im just going to drop the tank tomorrow.....ill try to test the pump to verify but im just going to put a new one in

 

[yourm0m1]

new fuel pump and it ran!!

thanks for all the help guys

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