Diesel Bombers - Need Help! 6.0 wont crank or start.

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- Ford Powerstroke 03-07 6.0L (https://www.dieselbombers.com/ford-powerstroke-03-07-6-0l/)

- - Need Help! 6.0 wont crank or start. (https://www.dieselbombers.com/ford-powerstroke-03-07-6-0l/123871-need-help-6-0-wont-crank-start.html)

Quote:

Originally Posted by bismic1 (Post 1148847)

Possible. Also, a shorted fan clutch can even prevent it from cranking without blowing fuse F2.22.
Fuse F2.12 is for power to OBDII port (and the cigar lighter).

Does the cigar lighter plug work?
Does the fuel pump come on when the key is turned to on (not cranking)?
Do the injectors buzz w/ key on?

Just an fyi - an electrical short in the fuel heater circuit, the transmission range sensor, or even the shifter handle can cause a no-crank. So can a shorted out v-reference circuit (at any of the sensors that have a v-reference circuit).

Also fyi - The PCM controls the ground for the start relay that is on the fuse panel under the dash. It is a pink wire if you need to locate it. If the OCM doesn't sense neutral or park from the TR (range) sensor, it will not ground the start relay. So, if you have power on two posts at the relay, but no ground ... it is either a PCM issue , the wiring (pink wire circuit), or the range sensor or its circuitry.

got to work on it this morning and first thing I check is fuse is 22, holding my breath......... bam it was blown!!!!!! Thank you Bismic you are the man!!! I replaced it and gave it a crank.... booomm it cranks again!!!! So relieved but she was cranking slow so I put it on a charge meanwhile replacing fan clutch. Gonna head to the auto parts store or Home Depot for some hard plastic sheathing to ensure the wire is extra protected! Still need to verify we get her to start after the battery charges, I’ll try it.

Glad to have helped.

Quote:

Originally Posted by bismic1 (Post 1148915)

Glad to have helped.

so, I got everything installed and it took a good 3 second crank to get going. Finally it fired up and running kinda rough and then soon settled in to a good idle. OBD is working again and i have connection with sct tuner abs obd code reader. All was clear no codes. I got low oil pressure on the dash read out and the needle is all the way down, checked the oil and it was not reading on the dip stick. I must of poured in about half a gallon to top it off. Tried again this time it started faster, but still no reading on the needle and low oil pressure on the message. Took it for a drive and the MPH needle is not moving either, but everything else is working. Checked for errors on the obd2 but it is clear. I cleared it just in case but no luck. She’s running fine, coolant is 198 oil 204 cruising around.

There is a very good chance that it is simply the oil pressure switch. It is not very sturdy and can fail when bumped. Often times it leaks a lot of oil when it fails. Check the connector first though ... it may have just been disconnected.

Oil pressure switch sending unit --- part # F81Z-9278-AA. There is an o-ring seal on it. Don't over tighten it, the threads strip easily! Just an fyi - the threads are 7/16 - 20 if you want to rih up a manual pressure gauge to check the pressure. The dash gauge is just an on/off switch indicator. If the oil pressure is over 7 psig, the dash gauge will register normal.

Oil pressure switch sending unit connector - WPT439 for Motorcraft (or 3U2Z-14S411-MHA)

I highly recommend getting an OEM sensor vs an aftermarket (I also don't trust EBay or Amazon for sensors - even if they "claim" that they are OEM).

Regarding the speedometer ................ do you have cruise control?

Ok I will check the OP switch connector. I dont have presence of any oil leaks, and this is the first time seeing this alarm. I do have a very slow persistent coolant leak that is making its way down to drip from my starter and from the front of trans which i am determined to find that source next. As far as the speedo, yes i have cruise control.

Since you have cruise control, I would tend to think that the lack of speedometer is an instrument cluster issue.

I would bet that you end up needing an oil pressure switch.

Quote:

Originally Posted by bismic1 (Post 1148963)

Since you have cruise control, I would tend to think that the lack of speedometer is an instrument cluster issue.

I would bet that you end up needing an oil pressure switch.

sorry were you asking if the truck is equipped with cruise control or if the cruise control is working ?

My question was (reworded) "Is cruise control working??"

Quote:

Originally Posted by bismic1 (Post 1148971)

My question was (reworded) "Is cruise control working??"

Ok, so magically the speedo came back online and i tested cruise control it is working. weird I didnt touch a thing. So truck sat for a day, and when I attempted a startup, I noticed the Oil Pressure needle move to the middle for like 2 seconds and then fell down. I tried to reach in there to verify if the plug was loose, but its was really an awkward position to reach into with my hand as well as using an extension to push down on the plug. All subsequent startups continued with needle not moving and staying down. I just thought it was peculiar that i had some life in it for a couple seconds.

Sounding more like an instrument cluster issue now, since you have several issues that really only have the cluster as a commonality.

Sorry that it can't be a more definite diagnosis, but that's the nature of internet troubleshooting.

One thing is for sure, you have oil pressure, otherwise your truck wouldn't start. If you could prove to yourself that there wasn't a problem w/ the oil pressure switch or pigtail, then I would be a lot more confident that the issue was the cluster.

CircuitBoardMedics do repairs on Instrument Clusters and would probably give you some troubleshooting help by phone.