I have a 2002 f-250 7.3 Powerstoke that won't fire. It has 200,000 mile on it. It did this about 3-4 weeks ago. Crank and crank and no fire. My water light didn't come on but thought what the heck. I drained the filter/water seperator turned the key to the on position 3-4 times then turned the ignition on. It fired up. I drained the filter this time to no avail. I bought the truck in 08. I was thinking it might be the cam sensor, but the previous owner had the cam position sensor replaced. Heard they had a recall on them and that the new grey ones are OK.
Any thoughts are greatly appreciated,
H20 Dawg ><>

check engine light on?
any smoke while cranking?
is it spinning fast or slow?

How old are the batteries?

It could still be the cam sensor a good code reader will tell if thats the case since it should set a dtc.

Replies so far. I don't recall the check engine light on. The engine symbol would come on when I turned the key to the on position (as with all my check lights), but I think it went off before I started cranking? It was spinning good when I first tried it but started slowing down when I gave up (I checked it with a volt meter just a minute ago-both batteries are @ 12.11 volts. I didn't have any smoke while I was cranking. I do have a chip/code reader. I guess that is my next job. It is a SuperChips Max Micro Tuner 1705. It was installed on the truck when I bought it and I have never changed the level or done a diagnotic on it. Oh, the batteries are from Aug. of 2010. I guess I need to get the book out on the code reader and hook it up.

Read the codes (if any) and put a battery charger on since they are getting weak. If no codes then you'll have to determine why you are not getting fuel into the engine since thats likely going to be whats keeping it from running. If its eletrical codes should be present so I would check for fuel pressure at the filter header while cranking and make sure that the engines getting correct fuel pressure.

I'm betting weak batteries.

I guess ChuChu1 gets the bow.

I've had a lot of things going on and just now had time to put the jumper cables on them. Whalah!!! Fired right up. Anyone that can't get the Ol' diesel fired up might try to give it a boost. I only run this truck to pull the boat. My next job is to go have them load tested to make sure they are good (they still have warranty on them).
Thanks ChuChu1

I had a 7.3, and when it wouldn't start I was talking about it at work and a guy said to check the batteries. I told him it turned over just fine. What I didn't know was the batteries were getting weaker so slowly, I never noticed it. Two new batteries and wow! Then it really turned over. Three years later, same thing. Wal Mart didn't make much on the sale, actually got 4 batteries for the price of two.

Another little trick I was taught was to give the 7.3 a shot of WD-40 while cranking it, and most of the time it will crank up. Just remove the duct to the air cleaner and spray it while cranking.

crank sensor or low on oil , low oil wont allow the injectors to work properly

Check out powerstrokehelp.com. They have a lot of videos that will help. You can learn almost anything about a powerstroke on that site.

or oil that is thin or dirty!

when was your last oil change?

Thats actually a bad idea it will put holes in the top of the pistons.

Yes and No

WD-40 is better than either
your safe spraying it as long as you don't over do it, but your correct, if it is overused, you will schorhc a piston or blow a h/g

I've got a 2000 7.3 and a few years ago the engine would occasionally just shut down at a stoplight. Had it checked and it was the cam sensor. The best news was when I learned that the cam sensor was a recall item and was thus replaced for free.

Old wives tale. It was standard procedure for starting the old 6.2 Chevy diesels after changing the fuel filters. Of course if you spray the whole can and then try to start it, you may cause some damage. I guess I should have simplified it, and wrote to start cranking the engine, THEN spray WD-40 into the air intake TILL IT FIRES! Then STOP spraying. I do hope there is no one stupid enough to use either.