• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

NEW FUEL PUMP,GAS GAUGE NOT READING ACURATLY!?

1

1990Pioneer

NAXJA Forum User
Location
Denver, Colorado
Hello all, I have a 1990 Cherokee Pioneer. I just had a total of 3 New fuel pumps installed consecutively. When I brought the Jeep to the shop my gas gauge worked fine as it always has. After the first fuel pump was installed I noticed immediately that the gas gauge was all over the place, not accurate, moving while I was at a stop etc..I topped off the tank on the way home and it didn't even read full, it would go to 3/4 then 1/2 then up and down a little when stopped etc...long story short...the mechanic installed another pump to get the gauge to work properly saying that they are made cheaply. That one didn't help the problem, he ordered another one (#3) from a different manufacturer , installed it and guess what?! SAME PROBLEM. He told me the only way I could be fixed is by installing an OEM fuel pump. Obviously at this point Im having a hard time believing that 1 out of three fuel pumps wouldn't fix this issue. The old fuel pump was original and needed to be replaced because it was defective and the Jeep was running like cr$p. The gas gauge hasn't worked properly since it was replaced.. Any thoughts or suggestions would be greatly appreciated.. Thankks again.
 
Unfortunate, one of the downsides of using inexpensive parts is the lack of quality that goes with the price. The fuel level sender is mounted to the pump and your Mechanic is probably correct in that you will need to buy a better part to resolve the issue.

Some parts just need to be sourced from reputable locations. All of the Sensors on the engine are prime examples.

That being said, you can go through and verify all of the electrical connections. From your post, the symptoms remained the same with each of the replacements. The question I have is, did the symptom remain exactly the same or, did they vary. If the symptom was exactly the same the sender may not be the root cause. If the issues changed with each pump installation then, there you are. Marginal quality. Makes one wonder just how long the pump motor will last if the manufacturer can't even get the fuel level sender right.
 
The fuel level arm can also be bent to more accurately reflect your gas level. The crap Airtex I have had to have that done. Also, it has less points for the level sender. The stock one had 20 or so, the Airtex had like 7
 
The symptoms remained exactly the same with all three fuel pump assemblies. I brought it to the mechanic because I just had back surgery, the Jeep was running very rough. We knew it was probably the fuel pump. The gas gauge never had any issues unitl after the first pump was installed.
 
i used a cheap replacement and did no thave this problem, the pump goes in the assembly so what you change is the pump itself not what reads the fuel level
 
88_cherokee said:
i used a cheap replacement and did no thave this problem, the pump goes in the assembly so what you change is the pump itself not what reads the fuel level
Click to expand...

Not always. It depends if you buy just the pump or the whole assembly. Figuring that the mechanic replaced the "pump" because of a gauge issue I would think its the whole assembly.
 
You may want to detach the fuel pump wiring harness connector from the fuel pump and examine the connector pins/cavities closely for corrosion and bent pins. Plug the old pump back up to the chassis harness connector, and using a helper in the cabin, slowly move the float up and down to see if the fuel quantity indicator follows consistantly. It may be that the problem is in your chassis wiring, not the pump module (?).
 
I UNFORTUNATELY do not have the old pump. I will get on the creeper this morning and check all the connections and the ground at the gas tank etc... I will let ya'll know what I find....
 
Wow that sucks... you are in the magical land of rust free jeeps though. I would hit the local pull a part and get a new sender, you want one from an 87-90 with the same engine as you have. Then just put the new pump and strainer from the assembly he installed into the used sender assembly.

And don't let mechanics throw out the old parts anymore...
 
Talyn said:
The fuel level arm can also be bent to more accurately reflect your gas level. The crap Airtex I have had to have that done. Also, it has less points for the level sender. The stock one had 20 or so, the Airtex had like 7
Click to expand...

Interesting!
 
Curious, did the new fuel pumps solve the crappy running performance?
 
I replaced my fuel pump a while ago with a brand new Bosch pump assemble. I had a little bit of an odd fuel gauge before hand, it wouldn't always go to the Full mark even when I filled it. It would never bounce or act funny, just not reflect a completely full tank. The new Bosch assemble acts the same way which I thought was odd. I figured it was the actual gauge and not the sender and decided not to worry about it.

Edit, I replaced the pump because of a leaking check valve, the gauge issue was never a real concern.
 
Ecomike said:
Interesting!
Click to expand...

If you have ever looked at the sender you will know what I am talking about. The arm with the float rubs against a circuit board with "fingers" on it. The stock has many, like 20 or so iirc. The Airtex only had like 7 or so.
 
Absolutely ! When the new pump was installed, it purred just like a kitten again. It's running great. I filled the tank yesterday. The gas gauge needle never reaches the full mark, it hangs around the 3/4 tank area. I was driving down a paved hill yesterday and I noticed that it was sitting on the full mark until I leveled out, then it went back to 3/4. Agrivating. I checked all of the connections to the sending unit etc, all looks ok.
 
It may be applicable it may not, but I had the same issues with a YJ. It eventually turned out to be the contact strip at the gauge cluster. A clean pencil eraser, some quality contact spray and a clean rag, all was good again.

It is such a tiny signal, that any connector almost has to have some influence, corrosion, oil, whatever.
 
The new pump did indeed solve the crappy running issue! Its purring like a kitten again. I filled the tank yesterday. The gas gauge stayed around 3/4 of a tank. I noticed as I was driving down a fairly steep road that the gauge was on full. When I leveled out at the bottom of the hill, it went back to the 3/4 area. I'm psyched that it's running good again, just very agrivating about the fuel gauge. I got spoiled I guess! Lol! I checked all the connections at the sending unit, all looks ok.
 
You must log in or register to reply here.

Similar threads

R
Fuel Gauge Troubleshooting
2
Replies
26
Views
4K
Rob Mayercik
R
P
Fuel pump will not prime
2
Replies
35
Views
222
Patrick dimel
P
WGxj
1997 XJ 4.0L AW4 Long Crank Problem
Replies
5
Views
89
Tim_MN
Tim_MN
Ecomike
87 Renix XJ No fuel, No brake lights, cranks fine
2
Replies
27
Views
863
Anak
Anak
Z
1990 renix electrical issues
Replies
3
Views
85
cruiser54
C
Back
Top