98 XLT 3.0 5 speed 4x4, got this from my nephew cause he was heading home one evening and it would pop and backfire when he would have to stop but would fire right back up and go, said it done this a few times and next morning it wouldn't start just cranked

So he was told converters where stopped up and cut the exhaust off it and didn't fix it and it sit for a few months as he's not mechanically inclined and got tired of it

​​​​​​I'm sortof sure I have it figured out but not 💯 percent LoL but I did the 50/50 test I had read about here over the past few days and fires up and dies, well after thinking about it that's what I had it doing before I added ether to the booster vacuum line, so I decided to clean the plugs and not sure about the 3.0 as this is my first but I've never owned a Ford that didn't have to have Motorcraft plugs to run right and this has ac Delco plugs in it and looked ok but wasn't gapped right and 4 of the 6 plug wires when removing them the connector stayed on the plug an one was missing half of the connector,

So that is first on my list to see if it will fire and run with plugs and wires replaced, main question I guess is they put a fuel filter on it and cut the lines on both sides and put fuel hose and clamps on it which he told me they done that about 6 months before it quit on him and never had a issue with it, But the IAG (I think) they also had a bolt out and had it turned about halfway which we already replaced but he swears it was that way when he got it which he had it a few years but I can't think of anything to make you have to open it like that other than it going bad,
have pressure on the Schrader valve off the fuel rail but due to neighborhood can't even lay under it and hear the fuel pump come on, as that was my first thought.
Any thing at all you may have discovered and want to pass along is truly appreciated, thanks in advance

Skinny
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Welcome to the forum

If its starts and then dies after 50/50 test then spark is working and timed, the fuel injectors are not opening, assuming you are correct about the fuel pressure

Will it keep running if you keep adding fuel manually?

 

Not sure, I got it to start before by feathering the throttle and kept it running when I got it to pull it on to the trailer when I picked it up but I had to hold it to the floor till it idled up and feather it several times to get it loaded, I can't say how much pressure it has on the fuel rail as I just mashed it and it shot fuel out like a cannon, then turned the switch on for a few seconds and repeated 3 times and it would do the same, don't have a pressure gauge other than for tires.
this is the reason I'm wondering if plugs and wires may fix it or as you said injectors possibly having issues? I did check the wire on the coil and battery reading 12.4 switch on it read 11.2 if that is something I need to concern with as well.
Thanks for the response Ron D, I've learned a lot and remembered a few things from your responses I've read the past few days

 

How old is the gas in the tank?

If you have any pressure in the fuel rail it should start and then stay running.............................unless fuel is bad or injectors are clogged

In 1998 the computer runs both spark and injectors, so if spark is working it would be a long shot that computer is not opening injectors


Long shot
Unplug the TPS(throttle position sensor) and try to start
it's a 3 wire sensor on upper intake, on throttle plate rod
If TPS is shorted computer will shut off fuel injectors but leave spark on

 

Thanks, I'll unplug the TPS and see what it does, if the same then I'll see how it does keeping fuel added after I get it started, I have to assume that the gas is about 3-4 months old but I did add some fresh to it as well, didn't think about that to be honest I added some to just make sure it wasn't out, I'll also check all the fuses and relays while I'm out there, I'll let you know how it does in a bit, thanks again

 

Ok Ron, it fires right up misses and dies, with and without the TPS plugged or unplugged, they have replaced the plug on the TPS which makes me wonder if they wired it wrong when replacing the new pigtail plug for it? I've a brown and white striped wire and 2 grey wires one with red stripe and 1 I don't remember what the stripe color of the other is but the pigtail has 3 solid white wires but it has 0 throttle response

 

Oh forgot, I believe the light is burnt out for the check engine because it doesn't come on at all, my son who originally was going to buy this truck got codes for it but didn't write them down but he said don't remember the codes but that it wasn't on when he put the code reader on it, and he cleared ones that were on it

 

Buy a $10-$15 OBD2 bluetooth code reader, works on ANY Vehicle sold in the US or Canada since 1996, its the LAW, so not a Ford or even Ranger thing
And works with any bluetooth phone or tablet/laptop to read and clear codes
APPs are free or $5 for more advanced operations

I used an ELM327 for many years, had no complaints, few years ago I got the BlueDriver because I wanted to get transmission codes and chassis/body codes as well, but truly not needed as a first OBD2 reader

That would be the best way to narrow down any mis-wiring or sensor issues since you don't have a CEL at this time

 

Finally confirmed today that fuel pump is working, but had to open the gas cap to hear it so maybe it's just weak and not giving the pressure it should but doing plugs and wires tomorrow afternoon so I'll post any changes if any, and I've got a OBD2 on the way as well, I truly appreciate all the help cause I'm scatter brained lately

 

Found out the fuel pump is supposedly original but who knows, have a fuel pump and OBD2 Bluetooth reader coming tomorrow as well as plugs and wires so will post what I have once I get the exhaust welded back on and those parts replaced,pump is last because of my own curiosity

 

Ok only has one code and it's the TPS, P0122 so maybe something in the way they wired new pigtail?

 

P0122 Throttle/Petal Position Sensor/Switch A Circuit Low Input

Yes, either its mis-wired or TPS is failing

New now means NEVER TESTED, not "it works" so grain of salt on any "new" part now-a-days

TPS top wire should read as 5volts key on
Lower wire should read as Ground
Center wire is the signal out
All 3 wires connect to computer

The top wire and lower wire are shared with other sensors so you will see same wire colors, Grey/red and Brown/white

 

Ok, I'll check voltage and make sure they are wired correctly and post the results in a bit, thanks again for the help

 

Well checked the TPS plug an the brown n white striped wire had 5.3 volts and the silver red stripe wire showed as ground, but I did replace plugs and wires with Motorcraft plugs and car quest wires and after a few attempts of start an die it fired up and ran like brand new so cleared the codes waited 2 hours and fired it up again smooth as can be so after a bit I plugged the code reader back in and fired it up and now it's only code is to the O2 sensor which I figure will be fixed once I weld the exhaust back on tomorrow and hook up the one he cut the wires off of and hopefully takes care of it, thanks again Ron D for all the help so I could get it done!

 

Good work

Thanks for the update, it will help someone else down the road