2001 5.4 triton

Last week got my oil changed, coming off the oil change I went to start truck..nothing. Had to go WOT to get truck to start(no fuel smell in engine bay)

week goes by no issues

Today i get P0171 - lean bank 1

I had issues with vacuum leaks before, but the fact that I had to go WOT to start a
week earlier makes me believe this could be fuel related. Any input?


**Edit, on second thought..going to replace the fuel filter.

 

check the vac line elbow on the back of the TB. I believe these are known to crack and fail causing a vac leak.

 

gonna hit that with carb cleaner before heading to pepboys for a filter
ty

 

Sometimes having to give some throttle to start can be the iac valve sticking.

 

no dice on fuel filter(I assumed this, needed to be done anyhow) I shot some carb cleaner to the 90, couldnt tell a difference..can't even hear a vacuum leak. going to try the IAC

 

Been driving with the truck running like **** as i've been busy, going to take off the TB to get to that 90 tomorrow morning..going to clean TB while i'm at it. Any things I should beware of when removing TB? I'm in my GF dads garage and I don't want to end up pouring **** all over his floor.

 

tend to agree with IAC as a culprit.

when removing the Throttle body housing ( presume this is the 1st time for your truck)...I have had good luck with loosing the big nut on the EGR steel line up near the EGR valve itself 1st , it like a 28 or 32mm...this would be the hardest thing to crack loose & best to have the throttle body secure when loosing. The rest are all either 8mm and 10mm you will need a swivel to get to some of the bolts.

OH yes...SOME throttle body housings have coolant plumbed to the Passenger side...kinda looks like vacuum line T ( some kinda cold weather option) and there is vacuum lines that do go into it as well. this surprised me, actually I forgot and didn't stop to look closely when doing this myself recently. IF you only have 1or 2 vacuum line on the side of the throttlebody on the PS then you probably don't have this "option" if so then its like 4 lines...just note if the vacuum lines have clamps or not if so then beware they might have coolant.

otherwise just take your time and have a extendable magnet to help retrieve those bolts the slip away. and some shop towels

 

Thanks!! Got it off no problem, it was suprisingly clean. No blocked ports etc. I just bought a new IAC cause i felt like spending 40 bucks I can't find any issue as far as that was concerned though. Additional info so I have something to look at if this doesn't work. The truck is bucking between like 1200-1700 RPM almost feels like its starving for fuel. If i let off the gas the bucking stops. Idle remains pretty constant 650 but as soon as i hit the gas no power and bucking.

 

What got hit w/carb cleaner?

 

I sprayed out the TB and ports, egr ports. Got me scared now:o

 

no worries...it is just that the IAC does not like carb cleaner...now it cleans it very well, but tends to dry things out too much or is toxic to the little solenoid that activates it. WD40 seems to be the cleaner of choice for the IAC.

Did you ever get your truck running better?

 

Hopefully he did get it running properly. the bucking he was talking about sounds like my water in #4 coil problem. it bucked specially when i stepped on gas. might check plugs and coils????