New code & hard time filling gas tank.

[Mike65]

The newest issue with my wife's 99 Sport is we got a p1450 code & when we stopped to get gas on Thurs the filler kept kicking off. The attendant had to stay there & hold the handle to fill the tank. Back in the summer I replaced the vapor canister purge valve under the battery, the vapor canister, & the vapor canister purge valve on the vapor canister. The old metal line was badly rusted so I ran a new line. From what I have read online p1450 means unable to bleed up bleed fuel tank vaccum. What can I look for/check out?.

 

[boominXplorer]

Id start by checking the lines coming from the engine going to the vapor purge valve for collapsing.

 

[Mike65]

:UPDATE: I checked all the lines & they all look good so I had my wife try a different gas station & the truck filled just fine. I also had the PO171 & PO174 l/s & r/s banks lean codes. I did some checking & it seems a common problem is the DPFE sensor causing the EGR valve to allow extra air into the engine because it is not closing properly due to the DPFE sensor not holding vacuum. I did all the electrical checks & they all were OK, when I did the vacuum checks the sensor will not hold vacuum on one of the ports. I ordered a new DPFE sensor & the 2 vacuum lines & replaced it this past weekend & so far after 3 days no CEL. Keeping my fingers crossed.

 

[BrooklynBay]

Check the intake manifold gaskets for leaks. Those codes usually point to that area.

 

[410Fortune]

171 and 174 both banks lean
99 sport SOHC
intake plenum O rings are suspect
I would plan to replace both upper and lower intake plenum O rings
Good time to consider upgraded thermostat housing
Also a VERY good time to replace auto chain tensioners...since you have to remove the upper intake and thermo housing to do the drivers side tensioner
Use ONLY Ford tensioners

 

[RickOTR]

Error Code P1450 means the fuel tank is unable to bleed up fuel tank vacuum, and this has nothing to do with the fuel pressure sensor at the engine. The most common cause of this code is simply a defective Fuel Tank Pressure (FTP) sensor

 

[koda2000]

Just a thought...
There recently was a poster on the Sport Trac sub forum where the poster was having a hard time filling his fuel tank w/out the pump clicking off. It turned out his filler neck had a screen in it and it had become plugged with debris preventing good fuel glow. I know none of my Explorers or Mountaineers had a screen in their filler necks, but his ST did. I suspect my ST also has this screen as I've never been able to siphon its tank.