It seems that just a couple years ago I replaced the intank fuel pump on my truck.Thot I'd be good to go for quite awhile.Not.After a tune up in the fall,it was running great.Then it started cutting out a little when under a load,Goin' uphill at hiway speed and such.Checked the coil and such, everything is up to snuff. So I figure the fuel filter is gettin' plugged up a bit,not lettin' enough fuel thru to run at higher speeds.Go to NAPA and get one,gotta wait till I get my daughters car out of the shop,waiting on parts.It was -13 this morn.ain't layin on the ground outside today to change the filter.Anyways, went to town this morning to order lumber and windows for an addition I'm building and on the way home the tuck dies on me.I'm thinkin' I should have changed that filter when I tuned it up.So I turn the key a few times to push some fuel thru the plugged filter,maybe I can make it home.After about twenty ties,it stumbles a few times but never really starts.Then I remember when the other pump went out I had to whump the bottom of the tank with a 2x4 and it would start.Did that and sure enough,it starts.I guess that having to drain 3/4 tank of gas and dropping the front tank doesn't bother me so much as the fact that I gotta spend another 175 bucks for another Chinese made fuel pump. Oh well,at least I had a chance to vent a little without the wife yelling' at me. Sorry I vented on you guys, but at least you won't give me a good yellin'.

 

Hell man, I know how you feel. That kinda thing happens sometimes, as you know, and the my solution for parts like that is buy one with a lifetime warranty.

My Airtex unit (it's the entire Fuel Delivery Module) from AutoZone has a lifetime warranty. Yeah it's still a pain to change it but at least I won't have to buy one again. Paid ~$130 for it, but I don't know where you are so maybe prices are different by you.

What shape are your bed bolts in? If they look good (like they ain't fixin' to snap on the first try) then just pull the bed, or do what I do and use a 2x4 to prop it up while you work underneath. Use antiseize when you put the bed bolts back in, so it'll be easy going next time you want to remove it for whatever reason.

 

Hey Dixie, thanks for the reply. I thot about raising the bed last time but I have a bed sled kinda thing in thereThat's kind of like a big drawer back there I put all my tools on/in.Keeps me from havin' to crawl all the way up front to get stuffMaybe I'll just see if I can drive it long enough to burn up some of that gas before I do the deed.It's -13 today,so the gas will go down pretty quick.I live in west central MN for some odd reason.HaHaAt east my shop has a wood stove to keep the chill off.

 

Nothing like a nice wood fire when it's cold out. Here in Florida 40 is cold for me, nevermind -13! No woodstove but I do have a fire pit out back. I DO like it when it's cool out though, it knocks the skeeters down and you can actually park out by a lake or whatever and not get ate up. And, you can just leave beer in the truck toolbox... stays cold all night long!

 

Dont pull the tank

get yourself a couple Cam style the down straps.

Hook one end to the frame, the other end to the cross member to cradle the fuel tank. Pull them tight.

Then undo your fuel tank straps

Hit the cams to allow the tank to drop slightly so you can undo the filler neck.

Then hit the cams so more to drop the tank far enough down to remove the fuel pump/sender(it doesn't have to go far)

Then put your new one in.

Pull on the tie downs, attach filler neck

Pull further attach straps.

DONE

Takes about 30-40 min

 

Sounds like Brad has done this a time or ten.I got all kinds of straps,last time I made a cradle with a piece of old diamond plate and some long carriage bolts,kinda like a tranny jack setup.Worked pretty good,but that has long since been recycled.Seems easier than messin' with rusty bolts. There will still be a couple to deal with but ain't nuthin' gonna happen till the saturns' outta there. My 48 has dibbs on the other side of the shop. Thanks for the advice guys.

 

Well,after not really wanting to replace the fdm on my truck I figured I better do some chekin' on stuff. Started the truck and it ran for about 2 mins. and died. Wouldn't start up again. So I figure I'll change the filter and that will help.Broke my little tool doin' it but I got it done.Don't know why the tool broke, it was all of -13 this morning.Ha,any ways I relieved the pressure at the fuel rail and barely got a dribble out of it before I did the filter. I just used my pencil to push the valve in. After the filter change it shot all the way up to the hood.Guess I got good pressure now .Went to start the truck and no go. Pluged the block heater in for about 2 hours and it did start. Ran pretty rough too.I never like to give it any throttle right after it starts, my OCD I guess.But it died a couple times and started right up but I had to give a bit of gas to keep it goin'.Now it's 11:30.Gotta go to work,jump in the van and off I go.Back from work now,trucks been plugged in for 5 hours now ,started right up and idled .But still very rough.Walked around to check the exhaust and it smells pretty rich on the gas side of the spectrum.I just did a major tune up two weeks ago.Could this be a stuck injector or maybe the IAC has gone bad? I kinda stumped on this one,any ideas or suggestions would be greatly appreciated.Thanks guys.

 

It could be a stuck IAC, a quick way to check is if you can keep her running smoothly just by giving it throttle, then you know that the IAC is unable to supply enough air.

But in your case, even giving it gas manually doesn't result in a smooth running engine, and the exhaust smells of gas too, so you got other problems. Get those fixed, then we can re-test for a bad IAC if you're still having idle problems.

I still think you're on the right track with a bad FDM. Just cause it makes pressure doesn't mean it's within spec... my 97 Thunderbird 4.6L had a failing fuel pump. Started, idled, and ran great all the way up to just over half-throttle. Past that, she'd sputter and couldn't make any power. A UPS truck could've beat her in a drag race at that point.

On the other hand, my 91 Ranger started, idled, and ran great up to 100% throttle until one morning I went to turn a corner. Let the clutch out and she flat out quit running... engine didn't even try to fire again. Did some checking there on the side of the road and found no fuel pressure. Fuel control circuits appeared to be working, so I got towed back, pulled the pump and found that it had locked up solid.

So, in my experience, fuel pumps die whenever the hell they feel like it, with warning if you're lucky but no guarantee that you'll get one. Smacking the bottom of the tank with a 2x4 and being able to start the truck right after is definitely not coincidence... that's a sure sign of a dying pump right there.

 

Well I pulled some codes today.Too cold to work,-25 this morning.Anyways, I got KOEO 173,and 327. Also KOER 172,538,and632.173 says HEGO always rich and 173 says HEGO always lean.Not sure what the HEGO is.The 538 is my bad I guess, and the 632 is prolly cuz the little wires down in the column for the OD cancle button are broke again. The 327 says EVP or DPFE circuit below minimum voltage. What does all this mean?The EVP has to do with the EGR valve I guess, but the DPFE I dunno. Any help would be greatly appreciated.

 

HEGO = Heated Exhaust Gas Oxygen (Sensor) aka "o2 sensor", it's a probe in your exhaust manifold and/or pipes that measures the amount of oxygen in the exhaust. When the computer sees a lean (high oxygen reading) condition, it tries to correct it by injecting more fuel with each injector pulse. When it sees rich it injects less fuel. That's why if you have a vacuum leak, it'll cause the o2 sensor to read lean and waste gas. How old are these sensors? When they get old they usually fail in a way that makes them stick at one reading.

EVP = EGR Valve Position (Sensor), a sensor that physically measures the position of the EGR valve pintle (the actual moving part of the valve). The code is telling you that the computer sees less voltage (signal) feedback from the sensor than it ever expects to see. I'd start by checking out the connections near the sensor. EVP sensor would be on top of the EGR valve itself. If you don't have an EVP sensor, then you have DPFE instead.

DPFE = Differential Pressure Feedback-EGR (Sensor). Sometimes this is used instead of an EVP sensor. It measures the differential pressure in the EGR pipe which lets the computer estimate how much flow is going thru it. Same problem as above, the computer sees a low signal coming back from this sensor. The DPFE sensor would be found near the EGR valve. Looks like a cast aluminum part with 2 black hoses that run to the EGR tube and a single (3-wire?) electrical connector on it.

 

Thanks Dixie, I knew what a o2 sensor is but I never heard it called a HEGO.Typed in acronymns at the search bar and got a list 'bout 3 feet long.The IAC is still pretty new,last year I think but it could still get plugged up somehow.A little carb cleaner will fix that. The O2 sensor is the original maybe,I haven't replaced it. I'll have to check out the EVP/DPFE sensor tonight after work. Thanks for all the help.

 

Dixie - was this for the 96 F150 in your signature? did you replace the FDM for the front or rear? what was the airtex part number? and anyone have any feedback on the airtex brand? lifetime warranty is great, but if its going bad every year on me, that warranty is going to loose its appeal real quick... thanks.