Welcome aboard, and hopefully your truck problem has been answered. Sent from my iPhone4 using Tapatalk
Okay so I bought the sensor. Can someone point me in the right direction to changing it. I'm pretty good with mechanics just point me in the right direction Tap Tap
Changed the sensor seems like it helped a little it hasn't died yet but it still runs rough as hell at an idle Tap Tap
Nm it still dies. I did notice there was a vacum under there that was just capped of with a screw but I didn't see were it coulda went Tap Tap
Not a good thing it was capped off, goes to something more than likely that needs vacuum. Could be a multitude of possible things, Vacuum leak, clogged fuel filter, fuel driver module, fuel rail pressure sensor, clogged injectors. Kind of hard to pinpoint an exact cause. If ya feather the throttle, does it run better over 3,000 RPM?
Yeah it runs perfect passed 1000 if I hold it to a thousand it's cool. When it starts it runs at 1000 then drops to about 700 kicks back up to 900 drops to 600 kicks up to 800 and so on until it hits 0 and dies then it starts right back up and repeats. It's good for maybe a min then it dies. The previous owner took it to Goodyear and they said they fixed it but it still does it. I think they are the ones that capped off the vacuum Tap Tap
Capping vacuum lines isn't a fix. Unless you got a new bad TPS, those "fly by wire" 5.4 3 valve engines aren't supposed to have an IAC (Idle Air Control) but the symptoms you describe make it seem like the problem to me. Can anyone else comment on this ? Do you have the diagnosis time and a compression tester? This would help isolate what is giving the problem. If all cylinders are within spec compression at least you will know compression isn't the problem and you get to see the condition of the spark plugs. Yet some are scared of pulling plugs for fear of breakage, the "if it ain't broke don't fix it" theory. If a plug is going to break, better on my dime than what a shop may try to charge to fix it during a tune up. This may or may not be the solution, just a suggestion. I assume no claim of responsibility.
i'm leaning towards spark plugs. i know, why would it be that, but he's having issues at low rpm, after being high for a bit (driving conditions). when was the last time you did a tune up? clean air filter and swap out plugs? that 3 valve shouldnt be doing that if you swapped out the TPS
well it's interesting it only under 1K. Idle is around 400 if I remember. I'd be interested in see what the fuel pressure is at both.
