Hi,
I have a 1998 1500 recently the gas gauge started flickering, Then it just started going nuts. After checking with a few other people i ended up changing the fuel pump and float. Guess what, it still flickered after this. I had gotten a good working gauge cluster. I installed that and to much amazement the flickering stoped. About an hour or so later it started flickering again but this time its flickering with the needle stuck in the full position. I do somewhat have a full tank of gas. I did check some connections under the power break booster that came from the fuel tank, but did not find anything loose. Ive never had any problems like this before with the truck. I do have an after market alarm system. Any more ideas on where to look to fix this problem is greatly appreciated. this is making me nuts LOL

 

i would recheck your cables from the gas tank
i ahd that problem too on my 88 turns out that the ground wire for the pump was shot so to speak the ground wire had came off the loom
so i just cleaned a part of the frame real good and then i put a new loom put it on the frame and it worked out great
if that dont work there maybe a fuse for the guage cluster somewhere
i no in my 05 crown vic that was the problem with the gas guage not working
so check the ground wire for the pump it should be located on the backside of the filler neck on the bed
clean take the negative cable of the battery before disconnecting it
clean the surface with a wire brush or even sand paper to get it real shiney and then reconect the ground wire then reconnect the negavtive cable and go from tehre
also did you make sure all the connections on the pump were good as in the plugs if they are loose it may cause the same problem

 

Thanks for the response. i checked fuses, all are good, the ground strap on the filler neck is ok. when you say loom, where about on the loom? when i put the new pump in it gave me a new 4-wire plug in that i had to splice and crimp. ireally dont like doing this, Id rather solder the connections but im sure the crimps are ok. Ill recheck the grounds and the plugs.

 

when i say looms i mean like the ends that are on the ground
and as fro you said you crimped the old onto the new
i have learned from trial and error that sometimes when you think your crimp is good its not
as i have found the hard way a few times when i was wiring my strobe lights in my car and bruned up a wire or too
also the old plugs maybe dirty take soem electrical connector cleaner to them and see if the dont help
and one more thing to think of mabe there is a short in one of the wires soemwhere along the frame
i would suggest starting from the wires you had to crimp and use a mult meter to see if any voltage or ohms are goin thru the wires im not sure as to what should be goin thru there as i dont have schematics.
so i would start there
also check all the plugs on the dash panal you said was good there may be something loose.
i hope this helps and check the fuel pump relay it may be bad or going bad
again you may need a mulitmeter fro that also
again i hope this helps

 

Today i was able to work on it a little. Checked the ground that runs from the fill tube to the frams. A-ok. Checked the ground that was in the rear bolted to the frame.A-ok. I wire brushed this stuff so it s good. Whats happening now is when i start the truck the gas gauge is perfect. then 20 seconds later it starts to flicker crazy. Still need to check crimps on fuel pump. I may just solder these. Running out of options as to what it is.

 

that would be the best bet is to solder them for a better connection
it sounds like its almost fixed but there is still a short maybe its from on of the crimps you havent soldered
keep us posted
and also when you put the new pump in this may sound silly but did you have alot of resistance while placing it thru the whole on the fuel tank
if so it may not be setting in there right when i had to replace mine in my 05 car i had not noticed that the float was stuck cause it wasnt down in the tank all the way where it should be i loosend up all the bolts and fiddled with it till it came loose then put it back in the right way
and also check your plugs on your fuel pump the are on the outside maybe the plugs are dirty or loose as the clips on them are very easy to break
check both male and female ends
if everything is still goin crazy after that i will be stumped also
one other posibility to check is the filler neck make sure it is all the way inside the tank that can cause air to get in there and may cause it to go crazy too

 

Will solder the ends this weekend. When i put the new pump in it was a little taller but it was spring loaded. Just like the old one. Pump is held in place by a large snap ring. Pump is sitting good. Ill recheck plugs. The new pump came with a new style 4 pin plug. it was all horizontal. Old plug was 4 pin but 2 up 2 down. I need to check the after market alarm system. read someplace that could cause issues. Dont know how ttrue this is. Im also thinking of trying to run a whole new ground wire but not sure what goes where.

 

yes i also read that somewhere
the ground wire should be black but sometimes the factory uses different colors

anyway the ground wire should be easy to folow it down form the filler neck if you replace the wire splice it so as you have enaugh room to put a wire connector on it i would say about an 2 inches from where the wire goes into the pump
let me no what ya find out as i am doing alot of reasearch about this problem

 

Have done just about everything. Found some more body grounds.Its all starting to point to the computer. Which will suck if it is.

 

i feel ya there
i have to get a new trans for my truck its gonna suck my overdirve is slipin and then yesterday the rest started to slip