Hi Folks, I have a 99 PSD, and cannot find the glow plug relay to test it to save my life. I suddenly developed a hard starting truck when cold (25 or so degrees out), it acts like it is the relay. I have a manual that shows it, but I cant find it at all. I have found 2 solenoids, one behind the fuel filter, and the other on the front pass. fenderwell. Thanks for any help. Has anyone else had this relay go bad? I should be covered under warranty, but I'd rather save the time if possible....

 

If it is still under warranty, take it in and get it fixed. The solenoid is on a bracket attached to the right bank cylinder head. What if that is not the problem?

 

I figured that is where it is, but it looks just like a starter solenoid. The stuff I show makes it look smaller, with a double plug instead of the two small posts.

I DID, however, find my lid to the fuel filter loose. Not enough to make it run bad, but enough I think it may have leaked off enough to cause a hard start, especially when the truck sat for a day and a half. So far, it has started out in the cold OK. I am still keeping my appointment with the dealer, though. Ever seen this happen?

 

Yes, it looks exactly like a starter solenoid. Did the loose fuel filter lid leak any fuel into the valley? If so it could have gotten a little air in the system causing a hard start condition. The glow plugs draw about 40amps each so if you had a clip on type ammeter across the battery cable while somebody else turned the key on for the first cycle in the morning it would read 320 amps (give or take 20). That would effectively test the solenoid and the glow plugs at the same time.

 

Hi Joe, there was a bit of fuel in the valley, but I am back to square one. It started in 15 degree weather, then the next day at work, I had to plug it in to get it started. I am thinking maybe a crack or bad internal connection somewhere in the GP system. Thursday it goes to the dealer. Good Idea about the amps, I'll try that today. Do you know anything about the relay looking like a starter relay, but the manuals showing the different looking one? I figure an update, maybe? Thanks for the help...

 

I don't know what kind of manual you have but there was an update on the glow plug solenoid (95 or 96 I think). The earlier style was smaller and had a modular plug-in for the small wires (it looked like a motorcycle starter solenoid). When you get ready to start it, leave the door ajar so that the dome light stays on and when you turn the key, activating the glow plugs, see if the dome light dims some as they cycle. If it doesn't take off and run with a reasonable amount of cranking, turn the key off for a couple seconds, then back on again to cycle them a second time. The dome light should dim ever so slightly as the glow plugs cycle. If it doesn't, either the solenoid is not cycling or it is not making the circuit when it does cycle. If your luck is like mine, as soon as you get within 50 yards of somebody who can fix it the problem will go away and not reappear until you get it home, making you (me) look like a recent escapee from a mental institution.

 

Hey Joe,

The plugs seem to cycle after the truck fires, the dash lights dim just a bit until it warms up. That update would explain the difference in illustrations of the relay. My manual is a Haynes, and I am not impressed. Thursday will be the day, and you are so right about the problem quitting in front of the shop. I thought I was the only one that happened to.

Also, before I hit the dealer, have you heard about a leaky oil pan seal on PSDs in general? I picked up a small overnight leak about 2" in diameter on my floor, thought it was my drain plug, but it is coming from the rear seal area. My LT. at work had the same problem, and his turned out to be a front pan leak. Any advice?

 

Well Joe,

went to the dealer today and he replaced the same relay I had tested and gotten voltage off of. He said it may have cracked and been intermittent. 100.00, but she should start this time. Asked about the oil pan gasket leak, and the service manager kinda flinched and said he had done a couple. Time to push on and beat the 100,000 mile game. thanks for your help. I miss my old 360 with points, plugs and stuff I can work on....
Dig