Hi Everyone,

My '05 Excursion recently started having rough idle and some loping when started cold. It seems to run good and idles pretty good when it warms up. I'm also getting a P0488 code (EGR Throttle Control Circuit A Range/Performance). I do have a BPD EGR and I don't recall if that would throw a code alone? I'm taking a trip next week and want to get it straightened out. Does it sound like an EGR valve issue?

I also thought about a battery issue, I know that can cause weird problems. I have Duralast batteries and they always seem to fail at about 2-3 years. I took it in and they say it tested good but I'm not always sure with them. Long story, but when cranking for longer than normal, the cranking power would drop quite a bit. Checked battery and had some corrosion. Cleaned and upon further inspection, the positive post is a bit eroded at the base and sunken in. The voltage was about 12.35 after sitting all night, a couple of the cells were reading lower than the others (about 50%, other 75%) when checked specific gravity. I tested voltage after batteries had been in the truck overnight, then unhooked from truck when testing.

I also thought about a glow plug/harness issue. The truck cranks for awhile before starting, 5-6 seconds sometimes, but not all the time. It starts up pretty quickly when warm. That's been going on for some time.

Anyway, Just wanted to get some advice before I take it in, I may not have time to mess with it myself. I will try to get a video of the rough start after cools down.

Thanks,
Steve

 

What is the IPR and ICP cranking when cold?
FICM reading just after it fires up cold?

Any glow plug codes?

Might be something as simple as injector stiction. For that you can try some fresh 5W40 synthetic diesel rated oil if you are not already, and some Archoil AR9100. Works wonders for many folks with stiction.

If you are not deleted could be as simple as a dirty EGR valve.

 

No glow plug codes. I will get check IPR and ICP readings later. I think the FICM is ok, always reading 47.5-48, but I'll check right after start. It's a 6 phase BPD FICM. I do have the Atlas 40 tune plus Gearhead tunes. If I recall, the previous owner had the BPD EGR installed, don't think it's deleted.

I was originally thinking stiction too. Changed oil yesterday, Rotella T6 with 8 oz of Rev-X. Didn't seem to make a difference. I have had a lot of oil leaking for awhile, no surprise. I haven't tracked down the source of the leak(s) yet.

Forgot to mention before, I have been getting intermittent check engine light for awhile. It eventually goes off, doesn't happen too often. I generally don't pay too much attention to the the CEL with all the mods.

Thanks,
Steve

 

One more thing, on occasion, I will smell exhaust fumes while driving. I believe that's a sign the EGR valve is sticking. I'm thinking about ordering a new valve rather than cleaning just to save time, of which I have little.

Edit: Just ordered an o-ring/gasket kit, going to try to clean EGR valve.

 

Okay, so I pulled the EGR valve and cleaned it, still rough idle when cold then smooths out. Anyway, the upper portion of the valve was gunked up. I have a BPD EGR and oil system. I have had a lot of oil leaking somewhere, going in the valley it seems, haven't dug into it yet. That's been going on for a long time. Attached a pic of the valve when removed.

 

Lol, yeah that one needs a cleaning and new o-rings, they look chewed up?

 

Got it all cleaned and new o-rings. I think I probably have an issue with the EGR throttle body/plate, need to take a look. If it's sticking, that would probably explain the rough idle at cold start. I have 222K on the clock, so some things need to get done. I'm waiting on my wife to get a new car then I get her 2011 Explorer as a back up car. Need to get the Ex in to a local shop that specializes in the 6.0. I don't have time to tear it down. Need to track down that oil leak. Going to clean the valley soon. There's so much oil build up that it smells of burnt oil after driving. No a good smell for the garage!