Hey guys,

I know this seems like a common problem on here but I thought I would run it by you and see what you think. My truck (2006 F150, 5.4L) has been idling rough and stalling out whenever I reverse up my driveway. My driveway is a bit of an incline and I notice the problem only happens when my foot is basically all the way off the gas... it then starts to sound like a diesel engine. This only happens at very low idle (i.e. reverse up my incline drive way or the other day when i was idling very slowly in a parking lot). I cleaned the MAF and had the spark plugs changed but that hasn't solved the problem. I also had it scanned but no codes came up, two mechanics have yet to provide me with an answer of what could be wrong. Anyone have any suggestions of what I can try next?

Thanks!

- Matt

 

I would check fuel pressure first.

If your engine has the IAC device check that too. Typically a failing or failed IAC will throw a code though---scan your PCM to see if there are any pending codes or others left in memory.