Fuel gauge problems [Archive] - Dodge Ram SRT-10 Forum

: Fuel gauge problems


2002srt10
01-18-2010, 03:19 PM
Well I had a fuel gauge problem today while driving with 1/2 tank of gas and 173 miles on the tank. My fuel gauge dropped to "E" and low fuel light came on. I went and filled truck up with 14 gal's of gas and when i started the truck gauge went to about 5/8 of a tank. Has anyone had this happen to them?

ViperJeff
01-18-2010, 03:28 PM
Actually the first time in 5 years I've even heard this one

Let me do some reading and see if I can find any clues

V2

2002srt10
01-18-2010, 03:37 PM
Thanks. I had something like this happen to my wifes C-5 vette but the vette is known to have this problem and there is alot of info on the vette fuel gauge problems on the web.I did a search for fuel gauge problems on the SRT-10 but came up with little info.I just added techron fuel additive to the tank.I did that with the vette and after the 3rd treatment the vettes gauge started working again.They say sulfur in the fuel can effect the chevys sending unit.

ViperJeff
01-18-2010, 03:38 PM
Well, from what I can tell is the signal goes through the PCM. I guess the first thing I would try is disconnecting the battery for a few minutes and letting the PCM reset (no, it doesn't reset the tune).

Then start her up and see how she reads

2002srt10
01-18-2010, 03:40 PM
Thanks will go do right now!

ViperJeff
01-18-2010, 03:47 PM
Looks like the signal sent to the PCM is a percent full signal. I think I remember seeing that your truck has the SRT-10 dash, so all the systems should be compatible.

Is your truck throwing any codes?

2002srt10
01-18-2010, 03:51 PM
I can't remember if when turning key on if all gauges would ramp up to max and then drop back to correct readings like my vette.I just turned key on and tach and speedo only ramped up to half scale and then dropped to zero but gas gauge just went from empty to 1/2 tank with key on and my tank is full minus about 34 miles.

ViperJeff
01-18-2010, 03:55 PM
2. INSTRUMENT CLUSTER
Perform the Instrument Cluster Self Test as follows:
Turn the ignition off.
Press and hold the Trip/Reset button.
Turn the ignition on.
Observe the Fuel Gauge during the Self Test.
The Fuel Gauge pointer should pause at each of these following positions: E, 1/4, 1/2, 3/4, Full, and back to E.

2002srt10
01-18-2010, 03:56 PM
How would I know if there are codes? I have no lights on dash or anything.

ViperJeff
01-18-2010, 03:59 PM
Lets do the Instrument Cluster Self Test first and see what happens, then I'll take you into the world of codes

2002srt10
01-18-2010, 04:02 PM
I did that and all gauges jumped up and back in stages including fuel. Then display came up with C-code then a 00 00 in display.

ViperJeff
01-18-2010, 04:08 PM
So I take it that the The Fuel Gauge pointer paused at each of these following positions: E, 1/4, 1/2, 3/4, Full, and back to E.

With that know, the PCM, wiring from the PCM to the Instument Cluster and cluster are good.

That leaves the wiring from the PCM to the fuel cell and circuitry in the fuel cell.......

2002srt10
01-18-2010, 04:11 PM
I can't recall if when I turned the key on before this happened if all gauges swept to full range and back or not like my vette.

2002srt10
01-18-2010, 04:14 PM
I left neg wire off the batt. for 5 min and reconnected and still have the same readings.

ViperJeff
01-18-2010, 04:15 PM
Hopefully someone will jump on and answer that question. I don't remember mine ever doing a full sweep when I turned the key on

ViperJeff
01-18-2010, 04:15 PM
How good are you with an ohm meter?

2002srt10
01-18-2010, 04:21 PM
The dash is SRT-10 but the overhead display is 02 ram. The compass and outside air temp work as does the trip meter but the mpg and distance till empty were always off "not correct" but fuel gauge always worked.I have put 1,300 miles on truck in under a month with about 5 fill ups and never had a issue until today.

ViperJeff
01-18-2010, 04:25 PM
Doing more reading, the "00" "00" on the odometer is OK

Back to reading

2002srt10
01-18-2010, 04:27 PM
I have a fluke 27&87 and a fluke 333 clamp amp meter along with a megger ect.I am a HVAC/R tech by trade plus I work on Johnson control DDC systems.If I know which wires to check and what ohms should be I can figure it out.

ViperJeff
01-18-2010, 04:32 PM
While I'm looking for the wires, here is how to check for codes

http://www.srt10forum.com/forums/showthread.php?t=10557

2002srt10
01-18-2010, 04:45 PM
Ran codes got nothing just ------- then done message. I should have run them before disconnecting the battery for 5 min but gauge is still around half tank.

ViperJeff
01-18-2010, 04:49 PM
Well, at least now you know how. If there is a constant failure, any codes will come right back

and they would be

P0460-FUEL LEVEL SENDING UNIT NO CHANGE OVER MILES - SRT10
P0462-FUEL LEVEL SENDING UNIT VOLTS TOO LOW - SRT10
P0463-FUEL LEVEL SENDING UNIT VOLTS TOO HIGH - SRT10

ViperJeff
01-18-2010, 04:51 PM
I wish I could help more, but my 2004 docs don't show the pin outs for what I'm looking for. I have the pin outs for the 2005, but as you could guess, I can't guarantee they are the same

V2

2002srt10
01-18-2010, 04:58 PM
Is there a plug at or near the tank that I could check with out trying to find it in a main harness under the hood?

2002srt10
01-18-2010, 05:03 PM
For now I will run the Techron fuel system cleaner in it and maybe it could be trash on the sending unit.If that don't work looks like I will need a new sending unit. Thanks for all the great info. I am going to go to dinner and burn some gas out of her and see if it drops to zero again.

2002srt10
01-18-2010, 05:09 PM
Its been a rough week. I also had a right mag fail on my plane this week.Still waiting on a new one to come in so I am grounded.A few weeks ago I had to replace a tranny seal on the Vette.I am afraid to go start the bikes now as repair funds low this month.

ViperJeff
01-18-2010, 05:13 PM
Dam dude, you better call a cab

ViperJeff
01-18-2010, 05:15 PM
While your out to dinner, I'll type up the 05 pinouts


You can still do a continuity test, if it passes, at least we have the right wires and we can go from there

CoupeDeAce
01-18-2010, 06:49 PM
You might have to pull the pump from the tank. I had a '05 Cummins come in with a similar problem, and the float had fell off the arm inside the tank. It won't throw any codes because the arm will still float, but just slightly lower, therefore giveing a lower reading on the gauge then what is actually in the tank. The arm slides against a contact plate, as it rises your gauge drops and vice versa.


That's just another idea.

2002srt10
01-19-2010, 08:16 PM
Well I put 100 miles on this tank and its at 1/4 so I will run it down until "E" and see how many miles are on it.I will refill the tank and if it goes to 5/8 or so and no codes come up I will go with the float falling off idea.Anybody know if the tank has to come out to get to the float?

ViperJeff
01-19-2010, 09:27 PM
Bad news, the answer is yes.....


I think the only other option is to remove the bed

V2

SpudRacer
01-19-2010, 09:44 PM
Umm, I'd opt from dropping the tank, personally. But that's just me!

da1chief
01-19-2010, 10:56 PM
But Tom, just think.... 6 bolts and you could lift the bed right off. All that new fresh serface to clean and paint, new bushings.... you could reach areas never before cleaned... :)

SpudRacer
01-19-2010, 11:08 PM
Don't tempt me... good thing my truck isn't here right now!

da1chief
01-19-2010, 11:36 PM
It's just sitting at Tony's.. You could run down there this weekend. Pull the bed, Steam Clean, Touch Up paint, new bushings, bed back on Sunday back home sunday evening :) :) :)

Don't think about that "Dirt/Mud Dauber Nest" betwee the Bed and the Frame. :D

SpudRacer
01-19-2010, 11:48 PM
Don't think about that "Dirt/Mud Dauber Nest" betwee the Bed and the Frame. :D

Man, you'd be lucky to even find a speck of dust between the two and you know it!

But the interior, that's another story. You should of heard Tony laugh when he saw the state of my dash right now... I haven't quite got it back together yet.

da1chief
01-20-2010, 12:15 AM
I know Tom, just having some fun... Heck as clean as your truck is.... The Wolf is clean but nowhere near in your class... :) Don't worry a couple of weeks after you get it back and no one would ever know it... :D

CoupeDeAce
01-20-2010, 01:26 PM
Well I put 100 miles on this tank and its at 1/4 so I will run it down until "E" and see how many miles are on it.I will refill the tank and if it goes to 5/8 or so and no codes come up I will go with the float falling off idea.Anybody know if the tank has to come out to get to the float?


Usually, there are two bands supporting the tank, 4 total bolts. There might be a heat shield or a skid plate you might have to remove first. Make sure you have support under the tank when you drop it. As soon as you start lowering it, disconnect the fuel lines, the connector for the pump, and fill nozzle. Then it'll just drop right out. Now, it can be done without special tools, but it is a good idea to get the special tool to take the pump off and on. There is a large plastic retainer that seals the pump down onto the tank. Once everything is loose, the pump will slide out. This will allow you to visually inspect the pump, and test the fuel level sending unit. All you would have to do is isolate the pump from the tank, reconnect the electrical supply, and start moving the arm back and forth and have someone watch the gauge. If it doesn't react like it should, you have found your problem. If it does react correctly, then you have to go back to the wiring and you just learned how to R&R a fuel tank and pump.

2002srt10
01-20-2010, 04:01 PM
Thanks for the info. I am going to run the tank down till the fuel light comes on then top it off and if the gauge only goes to 5/8 again I will know the float is off. I will then run it for 250 miles then drop the tank while it is light and repair float.Who knew a few holeshots would knock the float off the arm LOL. Really I have a bad habbit of topping off the tank to get a round number at the pump and may have filled it up to high causing a issue MAYBE just a guess. The truck has no codes and passed the cluster test and the gauge does drop as I drive so sounds like float is the issue.Once again thanks for all the info.

da1chief
01-20-2010, 09:21 PM
Just to be safe, you may consider securing a gallon of gas in the bed just in case the thing is off and the light doesn't come on.... That would be a bad thing.... :D

SpudRacer
01-21-2010, 07:35 AM
Especially if you're stuck putting in regular gas instead of premium.

2002srt10
01-21-2010, 06:35 PM
Not a bad idea to carry some gas just in case but gauge reads lower then actual so light should come on at around 160 miles on tank. I have ran truck to about 260 miles from full tank to get light on when gauge was correct.Some gas in a can would be better then feeling like a smacked ass on the side of the road.

CoupeDeAce
01-21-2010, 06:41 PM
I think the light comes on when you have about two gallons left in the tank, if it's functioning properly. I think. Thats' about 15 miles or so... Well, the way I drive.

da1chief
01-21-2010, 09:47 PM
Just remember the Military 7 P system.....

Proper Prior Planning Prevents PI$$ Poor Performance :D

Works in daily life as well :)

viperhauler
01-21-2010, 09:55 PM
it's a breeze to take off the bed, btw...almost a no brainer....

2002srt10
01-27-2010, 05:09 PM
Well I talked with one of our school bus garage guys today and we are going to take the bed off next saturday. He just did the same to one of our chevy 1500 trucks using 4 poles [ 3" black iron ] and the bus lift.He makes it sound easy just lift the truck unbolt the bed disconnect wires then lower lift with poles holding bed above frame. We will see if it goes as smooth as he claims.

2002srt10
02-22-2010, 04:48 PM
Well I did not get to take off bed yet because of the snow here in the mid-atlantic.I was going to do it this week but I took the truck out today and the gauge started working! WTF! I had the truck out a few days ago with 175 miles on my tank of gas and gauge at 'E' and warning light on. Well I went out today and the gauge started working again reading about 5/16 th of a tank. I had added a bottle of techron fuel system cleaner to tank a few weeks ago and had only run the truck a few times and 175 miles. I went to autozone today and added another bottle of techron then topped off the tank with 19 gal of 93 oct. gas.By this time truck had 194 miles at the fill-up so looks like 10 mpg on that tank. The gauge went to full after the fill-up so float must still must be on the arm in the tank.I am now thinking sulfur on the fuel level sensor in the tank.I will be keeping a close watch on this and will use the trip meter as a back up.Does anyone have any thoughts on this?

CoupeDeAce
02-22-2010, 07:27 PM
Well, I think you are right. Your sensor must have been dirty. Sometimes that happens. Maybe try different Gas Stations or something, I don't know?


Just keep an eye on it. Try instead of filling it up, put in gallons at a time. Like, 14 gallons even, so you know you should be on the half tank mark. Also, something might have just gotten lodged in there on the arm, and finally broke free or something.

ViperJeff
02-22-2010, 10:59 PM
Good News!

2002srt10
03-08-2010, 04:40 PM
I ran truck for just over 220 miles and had a little over a 1/4 tank on the gauge. I filled it up and it held 19 gal even and the gauge went to the full stop.after about 30 miles the needle was still on fill but off the stop pin so it appears to be ok. I did the math and come up with 11.62 MPG. How does this compare to others milage? I would say I drove it normal during this tank full with a 4500-5000 rpm pulls in second and third gear every now and then but other than that I drove like a normal person. what is the true realistic milage for the srt-10 in real life driving with a mix of in town and highway driving?

CoupeDeAce
03-08-2010, 08:39 PM
I get about 9 1/2 in town and my little cruises out into the countryside. I drive the ever loving juice out of her, though. So you are doing pretty good.