Thanks for the sticky.... After a rushed summer of having the truck in gear and rolling before the wait to start light was out, having to give my truck candy to start it come the first cool days of fall is a bit aggravating.
Last year it fired right up down to zero or however cold it got here in Upstate NY in the winter, and I never thought to plug it in.

GPR seems to be indicated as it started as an freak problem that suddenly became normal. It smokes like a steam engine at both ends when it balks about starting.
Back when it didn't have this problem, it would blow a good puff of white smoke upon starting and almost immediately clear to a more transparent blue which usually clears up when I remember to put fuel additive in...

94 PSD as it came from the factory except for being told of the installation of a couple used injectors and a splice job under a valve cover that was done before I got the truck.
190k miles.

 

Hello FTE Friends!! Was having some cold start issues with my truck, but after getting on here and reading some of the posts, think I've solved my problem. This has got to be the best web site ever!! Thank all of you for your knowledge and experience on the PSD, KEEP UP THE GOOD WORK.

 

Yes, Many thanks; while it was a conversation with another passenger on the train several weeks ago that tipped me off in this direction, it was this thread that confirmed it for me.

The old relay seemed to still be working fine when the truck was hot, but I did a voltage reading accross the main posts after it had sat overnight and found the open voltage to be 12.51 volts; and it did not vary when my sister turned the key on and the relay snapped "shut". Open circuit Ohms on the load side of the relay measured .5.

I needed to have the truck fixed by the next day, and as non of the hometown (PY) parts stores stocked it, I found that Geneva had them at Advance Auto Parts ($74) and Friendly Ford ($94).

The guy on the train told me he changed his relay annually, and I hadn't in the three years I owned my truck so I thought I might save a trifle in the long run if I spent the extra $20 for the box that had the Ford decorations on the outside - now for a little rant - When I spend $94 for a relay that I know it would not cost $10 to produce at the local Rochester Delco plant (or some similar place) does it come with a little dollar store styled sticker that sez, "made in Mexico", and even then, they can't afford to pack a new set of nuts with it? The least they could do to bolster my confidence is to have an oval stamped in the plastic relay housing!

I'm certain that the cheaper you can get this relay in your hands, the better, for they probably all get punched out at the same place anyhow. My old nuts were quite burned, and as the old relay disintigrated as soon as I started to mess with it, they were a bit of trouble to reclaim. [/rant]

Truck starts like a charm; the other day when it was in the teens, she shivered a bit more, and smoked more like a self respecting diesel should.

 

You, and esp. the guy on the train, would save a lot more by buying a Stancor relay, and taking care of it for good.

Annual relay replacement?

 

I don't know if I'd replace the GPR annually unless I was having serious starting problems with it. My old (two years old) NAPA GPR 110 is starting to slack off on cold-weather starts. When I'm ready to replace it, I'm going with a Stancor relay.

Glad to hear you fixed the problem.

 

Stancor is Highly recommended, I've had mine for 6yrs with no problems (Knock on wood)

Robb

 

I'm sure he wasn't changing it more than he had to... lol. But I agree, especially for the prices ya'll are saying you can get the Stancor relay for in the first place. I just wasn't in the mood to wait a couple days and possibly fool around with fitting it.

Just double checking, you say you wire that thing the same as the OEM style, and still fit it nicely under that IDI Powerstroke facade? I reckon I'll get one coming for a spare when the cash thaws out sometime. Things always work better and last longer when a superior spare is on hand :wink:.

 

Some people claim that their Stancor doesn't fit under the "Darth Vader" cover, but I've done two, and they both fit fine. And yes, you wire it in exactly like the OEM. Neither the "coil" (small terminals) nor the "contact" circuits are polarized; that is, it doesn't matter which big-lug wire goes on which big lug, and same goes for the smaller wires.

Corollary to Murphy's Law; and conversely, within a week after throwing out a spare part that "you'll never need...", the original part fails.

 

Is there any problem with turning the switch on and leaving it on too long warming up the glow plugs? Can you burn anything out? My wife had my teenager start the truck this morning. Zero dgrees. battery was run down - I'm not sure what happened. Next time I'll just tell her to wait till I get to it.

I threw the charger on it and put a block heater on the oil pan it started nicely after 1/2 hour and after running it for about an hour it seemed to clear out pretty well.

 

Glow Plug relay is controlled by the PCM...generally will stay on for a max 2 minutes...unless you turned the key on, and off every two minutes to cycle, eventually that will drain the battery some and probably tax the glow plugs....I am sure there is an eventual duty-cycle life time for these plugs...have not seen that number...

 

Well, my 96 7.3 is getting hard to start in the morning again, now that it's cold (and I live in Phoenix). I was looking at the Haynes manual at troubleshooting the relay and from what I read, the relay was only used on the earlier 6.9 engines. They speak of testing the Control Unit. Is that the same as the relay?

 

There's a guy on the Saturn site I tread occasionally, who recommends the Haynes manual for wiping your hands while working on your car, so you don't get grease on the FSM pages. If you can't get your mitts on an FSM, the info you find here or on any of the diesel-specific forum sites will be better than the Haynes.

The OBSes have relays. The California-bound trucks have a shunt on the relay that distributes the power separately to the two banks, and the PCM somehow monitors this. But the relay itself is the same. It's not a "solenoid" or "control module", it's just a simple normally-open relay (okay, Stancor sometimes gets faincy and calls it a "contactor").

 

Fleetsidebob,

Welcome to

I agree with the above comment. If you need to replace the GPR, you might consider a Stancor unit. You can do a search for it and read about the pros and cons.

My NAPA GPR-110 is several years old now. When I'm ready to replace it again, I'm going with a Stancor unit.

 

Before you go replacing parts. Try jumping the Glow plug relay with a screwdriver across the large terminals for about 30 seconds. Jump in the truck really fast and try to start it. If the truck starts nicely, you have a bad relay. If it doesn't start, glow plugs are the culprit.

 

I missed that post completely.

The early 6.9 engine had a controller that screwed into the coolant jacket to regulate the glow time by engine coolant temperature.
Ideal setup, but unfortunely it also had a bad habit of failing in the ON position, toasting your glow plugs.

The 87 6.9 and all of the 7.3 IDI engines used a solid state controller that sensed the resistance of the glow plugs to time the glow cycle.
Down side, the glow plugs came on every time you turned the key on for at least a couple seconds and when two or more glow plugs burnt out, the system was disabled.
That system was also very picky about the glow plug resistance, anything outside .5 to 1 ohm per glow plug altered the glow time.
Both of those systems had a trouble shooting guide. (the old style 6.9 system was three pages long)

The Power Stroke glow time is controlled by the PCM.