[N8tiv34]

my father passed down his 2002 F250 to me... im having some issues with it now.... . i replaced all eight glow plugs about two months ago, and the GPR a couple of weeks ago and still is having a hard time starting, it starts up when i plug in the heater, and runs great after that.... any thoughts?

 

[N8tiv34]

also when i went ro get my GPR i seen two parts under Glow Plug Relay, i was wondering if there are two sets of GPR's haha

 

[klhansen]

There are a couple of flavors of GPRs. Mainly the difference is the position of the terminals after you mount it.

I think I put a listing of GPR part #s in my Hard/No Start post in the FAQ subforum (link in signature).

I've had OEM GPR's last as little as 4 months. Now have a Stancor relay installed, which should last much longer than any stock size relay.

There are other reasons for hard starting, such as weak batteries, starter, etc. The engine needs to spin at 100 rpm min to start. Slower causes less compression which is where the heat comes from to ignite the injected fuel. Plugging in does a couple of things. It thins the oil a bit, relieving some of the load on the starter, and it heats the engine, giving the cylinders a higher air charge temp before compression heats it up more.

 

[N8tiv34]

cool thanks, also i was reading there that... there could be a problem with the "PCM circuit" that tells the GPR to activate? where would that be located?

 

[woodnthings8]

First thing you need to do is to verify the glow plug post is getting power with the key on. This will only be for a minute or so. Check the post when the engines cold as when oil temps are warm, they do not activate.