Hi I picked up my first diesel (2000 f250) and currently trying to smog it for the title transfer. Anyway it came with a tuner so I returned it to the stock setting and the CEL immediately came on. It is throwing P0677, P0675, P0674, P0673, P0672, P0671.

I live in CA so it's never too cold but some mornings I have a hard start and white smoke. But the white smoke goes away after the initial start and after the truck has ran I won't have a hard start the rest of the day.

What's weird to me is when I put it back on one of the custom tune settings the CEL is no longer on and the only code I got was P0380.

Could this be as simple as a bad GPR?

Thanks.

 

Welcome to FTE!

P0677 Glow plug #7 circuit failure.

I do not have a listing of the other codes as to what they are. I believe California trucks have a different relay than the rest of the trucks across the country. A faulty relay would cause hard starting when cold. How long does the Wait To Start Light stay on the first time you try to start it in the morning? 5 seconds, 10, 20,?

 

I messed up. The codes are all the same just on different glow plugs. P0677-P0671 (except P0676). Any idea why I could be getting circuit failures on all plugs?

I would say the WTS light is only on for about 5 seconds.

 

You may have a problem with the UVCH (Under Valve Cover Harness) that supplies electricity to the Glow Plugs. Or, you may have faulty glow plugs. If you end up doing GP's, use only Motorcraft. Other brands are known to swell in the heads and break off when you go to remove them. Thus, requiring a head removal.

 

If it is a Cali truck you should have something that looks like this GPCM:




If it is a 49S you'll have something that looks like this GPR courtesy of PaysonPSD:





Wiring diagram for both:

 

In the People's Republik of Kalifornia seller is obligated to smog, not buyer.

That said let's fix your problem.

Where are you located?

Need to remove or hide any chip switches.

Could just be plugs not seated on the GPCM.

Any other mods?

 

I'm an idiot and didn't know it is the sellers obligation to smog. To say the least that ship has sailed. I'm located in Corona, CA.

I didn't get a chance to look under the hood last night to see which type of GPCM I have but I plan on checking the connections later. A bad connection makes sense because I'm getting a open code for each plug(except for #6). Do you think they could all go bad at once? If they were bad I should always have issues firing, wouldn't i?

I hope it's not the UVCH. The truck is a monster 10" sitting on 39s. I imagine it will be a nightmare trying to remove the valve covers. It sure would be nice if it's just the connection at the GPCM. But I doubt I have that kind of luck.

All I know is Tuner, intake, exhaust. They were all on the truck when I bought it.

 

If it really comes to removing the covers.... A couple of old blankets and a step ladder.... climb up, toss the blankets on top of the engine, stretch yourself out over the thickly laid blankets, and wrench those covers off.

I (and many others) have spent many hours laying on top of the engine like that, and it's a cheap and almost comfortable way to do the job.

 

I'm sure I'll be fine im just being a puss. I have a bunch of old couch pillows I use to lay on.

 

Oh and for the P0380 code anyone know what side circuit A is?