I have a 2005 6.0, and this issue just started today. While driving through town at about 30-35mph, the engine kept cutting out for a split second and then recovering. I noticed the RPM needle dropping each time. I turned around to head home, but it completely died at 30mph. I didn’t lose 12v power, just coasted to the side of the road, and it started right back up. I drove home without issues. Sat in the driveway, idled and revved fine.
Nothing has been done to it recently. About a year and a half ago, I replaced the injectors, glow plugs, glow plug harness, glow plug controller, FICM power supply, and new tunes.
No codes, no leaks, and nothing else unusual. I didn’t notice any issues with oil or fuel pressure when this happened. FICM voltage seems fine.
Any ideas on what I could check that wouldn’t trigger a CEL? My only thought right now is to let it idle in the driveway and try moving around some plugs and harnesses (thinking about the FICM and CPS harnesses?). If it was the FICM or CPS themselves, I’d expect a code, right?
I had something similar happen with my truck, and it turned out the EGR got stuck. The truck started running rough, cutting in and out, and then died. I turned it off, started it again, and it worked fine. I replaced the EGR valve, as they can get pretty clogged up, especially with city driving and heavy idling.
I had a similar issue when my crank position sensor failed. The truck would stutter, and eventually, it stalled while driving. After replacing the sensor and pigtail, it was like new. The tach dropping out could be a clue.
It sounds like the FICM connector locks might have broken. The connectors can back out, and the harness sits on the driver side valve cover, which can cause it to ground out. Try pulling on the engine harness while it’s idling, starting at the PCM on the inside driver side fender and working over to the FICM on the driver’s valve cover.
@Pat
This happened to me twice, on two different trucks. Once it was on the FICM itself, and the other time on the computer side. The broken tabs let the connector work loose.
I’ve been dealing with random surges and finally decided to look into OBD2 scanners. I went with the Vlinker FS since it’s Forscan approved. I’ve been using the CarScanner app and it’s been helpful to read electrical values and see what might be dropping out. My issue is intermittent, so it was all just guessing before, but this could help.
Start with the fuel and air systems first, then check the FICM. After that, you can look into the oil-related components. It does sound like it could be an electrical issue, but start at the basics first.
Just throwing out an idea here: Have you checked the fuel pump relay? It’s located in the fuse box under the dash on the driver’s side (left side). It’s soldered onto the board and can’t be replaced easily, so you’d need a rebuilt or used fuse box from eBay. Sorry if my terminology is off, I had to replace mine a while ago.
I had a similar issue, and it turned out that the IPR pigtail was frayed. No codes at all. I ended up replacing the pigtail and valve while I was at it.
Oops, no one has asked yet—are we dealing with a 6.6 Duramax or a 6.0 gas engine? You’ve mentioned both, but you can’t have both a FICM and glow plug module along with 70psi fuel pressure. Not sure how your AI didn’t know that trucks don’t come with both.
@Orion
Huh? I’m clearly talking about a 6.0 Powerstroke, which does have a FICM, glow plug module, and with the blue spring kit, I’m getting 65-70psi fuel pressure. You do realize there’s a 6.0 Powerstroke, right? This is a FordDiesels forum.