Hard to Start: 7.3L Diesel

[Nugget Hunter]

I have a 2002 F350 that is hard to start with the first start in the morning. It will start then it will die. I will do this about three times and then it will run fine and start fine the rest of the day. Is this a glow plug problem?

[mrjohnwayne]

Sounds like it is a glow plug problem. What are the ambient temps in the morning and throughout the day. Are they close to the same? How long after the first start/drive will it sit before restarting?

How many miles are on the truck. could just be the relay and not the actual glow plugs.

You can test the relay to see if it is dropping to much voltage.



it is on top of the motor behind the ac compressor. there are 2 relays. The first is for the AIH system. The second (furthest from the front) is the glow plug relay

the wire with the boot is the feed wire (bat). The wire "circled" is the feed to the glow plugs.

hope it helps

[Nugget Hunter]

It looks like you have got me going on the right steps. Let me try to answer some of your questions.

The mornings are cool for Oregon summers: 45-50 but afternoon's are 70-85.

Once it starts in the morning it seems to start well for the rest of the day.

I think what you are saying is put a volt meeter on the power in and also on the power out to the glow plugs. Should they be the same???? 182,000 miles

Also thinks for the picture; it's better than words.

Jerry

[mrjohnwayne]

yeah if it is that cool in the mornings and warms up to the 70's-or 80's during the day to me it seems like the glow plugs aren't warming the air in the combustion chamber enought to promote combustion.

Yes if you test those 2 poles they should be identical or a small variance in voltage with the key on. Key off there should be no reading on the glow plug side. also with the key off check the resistance between the too to see if there is any. With the key off there should be none.