2000 7.3 F250...know a few mods were made before I bought it last year...cold starting sumbich last two winters...replaced glow plugs last year but not gpr - something about trusting automotive professionals (smh)...went to replace gpr three days ago and bam!, two gpr relays with one being pigtailed. Tested with a idiot light (derka derka derka) and the old original showed good with the add on showing foul. Replaced the add on with the gpr-110 and it started that day...next day was like crapping poopsicles - NOGO. In a fit of anger, I said screw it and pulled the original gpr and put the replacement in place. Now when I turn the key I am getting a vibration and sound from black box behind starter relay? on the passenger side fender well and still goose eggs on the gpr. Yesterday I bought a real fricking test meter and attempted to test the gpr...battery lead reads titty sprinkles but the opposite lead is all over the place like Ray Charles piloting a chopper while riding the white dragon. Add the damn sound from the black box and I am in the running for Dysfunctional Veteran.

 

When you say two GPR's...........Is this a California model rig with an AIH. Yes they were built with two.

They look Identical.

Way too many things to address here so let's just send you to the cold start thread so you have an abundant amount of info to isolate your issue.

Search, "Cold start" in the window above. This is one of the main topics in the forum.

If you don't have enough to get you going. Post back.

Denny (Check and clean every connection)

 

Below is a link to a cold start thread.
https://www.ford-trucks.com/forums/1...rt-issues.html

The 2000 model year has two relays side by side. One is for the glow plugs and the other is for the AIH air intake heater.

Next, the sound that you are hearing is probably the vacuum pump running. These trucks rely on that vacuum for a few things: locking and unlocking the ESOF hubs on 4x4's and for the mix doors on the heating and a/c system.

If that is it, then no worries there. It should automatically cycle off after about thirty seconds unless you have a vacuum leak.

 

Welcome to the forums! Thank you for your service!

Below is a link to the GPR relay modification. If you have to fix it, you may as well only have to do it once.

Welcome to guzzle's White-Rodgers (Stancor) GPR replacement Mod Web Page

 

The CA emissions model would have one relay for the IAH, and a control module for the glow plugs. The 49 state version has two relays, one of which is taller than the other.

 

You guys are as good as titty sprinkles...

Been through the Cold Start thread...at least 11 pages before I started going bat guano crazy...

As to the relay references...correct on the front (towards grill) being the AIH relay. Behind that (towards firewall) was the original gpr. Attached to the gpr mounting post towards the driver side, was a single bolt mounted secondary gpr (relay) that had a larger gauged wire piggybacking from the original battery lead to the secondary. There was also a red smaller wire piggybacked from the grill side small post to the secondary gpr. To note, the blue wire grouped with the glow plug wires (yellow and brown) was running to the secondary gpr as well. In jhl's picture, the secondary gpr was where the number 9 is pictured.

Jhl, you are better than titty sprinkles. The sound is the vacuum and it does shut off as you said. The sound however, is a damn knifehand to my hearing...or what little is left.

This forum has been a blessing...before I joined and since. The truck is still hard to start but sounds much better. Believe the starting is related to swapping out the fuel filter while waiting on responses and reading this worthless Chilton. Friend related it to priming the system after running out of fuel. I also believe I need to replace the batteries. They act up in the winter draining much faster than normal. Life at 7300' elevation in SW Colorado sucks in the winter...when you rely on your PSD. To note, Lurch has 233000 miles...I got him at 205000 miles.

 

Life at 7300' elevation in SW Colorado sucks in the winter...when you rely on your PSD.

Change to Rotella T6 (or any full synthetic 5w-30) at your next oil change, if you have not.

(I live at 7000' in Colorado...)

 

Steve - Absolutely love the Rotella T6. Use it exclusively unless I send the wife to get oil...than it is the T5.

Suppose I should look this up on the Cold Start thread but...running the multimeter over the gpr posts shows 14v at both little posts and the battery large post. GP wiring side shows 0. This is buenos, no? Truck has been running about 10-15 minutes.

Good news...ran some jumpers to the truck via my buddy's Jeep...sumbich started right up after getting the fuel pushed through.

 

1. As mentioned, synthetic oil in the winter.
2. GPR test: Meter across the large posts on the GPR, set to volts DC. Key off - 12 volts. Key on (when first starting) - 0 volts. Antyhing other than that, more investigation on the GPR is needed.
3. Grounds: Meter set to Ohms. Probe on battery 1 ground and the block, zero ohms. Probe on battery 2 ground and the block - zero ohms. While the batteries have a common positive connection, the ground connections are separate.
4. The last link in my signature has a concise list of things to check for hard/cold starts.
5. It has been my experience that our batteries last about 4 years on average in very cold climates. After that point, the GP load on cold batteries can make for hard starts.

I take good care of Stinky, but I recently found a weak ground on the block to one of the battery cables - and it took a lot of work to get the connection solid. I imagine that after 13-16 years, I won't be the only one discovering this issue.