I normally just replace them as they go bad, but I don't bother to remove the injector lines either so there is no efficiency for me to do them all at once. I pretty much treat them like light bulbs and replace them when they burn out. I usually have a couple of extra new ones around anyway. After you get to know the engine, you will know when you have a bad one by the way it starts.

Does anyone have a GP reamer I could rent for a decent price?!

James

__________________
1987 Mercedes 300SDL; SOLD
1985 Mercedes 300D; SOLD
2006 Honda Pilot - wife's ride; 122K;
1995 Toyota Land Cruiser - 3X locked; 182K

Merc,

The GP does not have a short, it is open, I.E. infinite resistance. If the GP had a short it would blow out the GP relay fuse.

The failure mode of a GP is almost always an open circuit like a burned out light bulb. In 35 years of MB Diesel use, I only had one GP thet had a short and that was a series loop type GP in a 220D.

NO, U don't have to replace all the GP when one burns out. They are parallel plugs and work independently. I always keep a spare GP in the car and replace as necessary.

P E H

James, while you are at it, take a close look at the inside of the sockets in the plug and at the mating prongs on the relay.

If you see any whitish or greenish powder, you have corrosion on the contact surfaces.

Corrosion can prevent current flow to a good GP, and it will act like it is burned out or the wire is broken.

A few sprays of electrical contact cleaner (NOT WD-40) and 6-12 plug-unplug operations will clean the contacts.

For stubborn corrosion, you can clean the socket with a pipe cleaner, or some light emery paper. You don't want to scrape much metal, just remove the build-up. Also, wipe the pins on the relay connector.

It is an well worth the time.

Yes - you're right... I meant to type OPEN...not a short... THanks.

__________________
1987 Mercedes 300SDL; SOLD
1985 Mercedes 300D; SOLD
2006 Honda Pilot - wife's ride; 122K;
1995 Toyota Land Cruiser - 3X locked; 182K