Fuel Sender Replaced - SES Light Still On

[Redfern]

I have an '04 EB 4.0L. A few months ago, my fuel gauge dropped while driving, the SES light came on and I had the code pulled. The code said the fuel sending unit was bad. I recently had it replaced, but after driving less than 25 miles the SES light came back on - with the same old code. Replacement unit has been re-checked and verified as good, but the SES light remains on. Battery was replaced today (getting old anyway), but SES came back on after just 5 miles. Haven't been to the dealer, and my local repair guy now thinks there's something wrong in the instrument cluster and the wiring for the SES light. Anyone experience anything similar? Thanks.

 

[05_moutianeer_mn]

A Flex fuel V6 has a fuel sender with a float and a electronic resistance sensor that measures the resistance of the fuel to determine how much gas is in the tank (possibly for message center miles to E indication) then down line under the hood they have a Flex fuel sensor (very expensive, hundreds of dollars) I think determines how much Alcohol is in the gas. E85 or E10 or E zero. The engine still needs to know in order to set the fuel trim map (ie Flex fuel).

I’m attaching a long story of my fuel gauge and Check Engine Soon story (Saga).
It may or may not help.
Long story short is try to add some Chevron Techron fuel system cleaner at about 150% to 170% recommended dose .
About 3 bottles per full tank .

So I bought a 108,000 mile 05 mountaineer with a 4.0 L v6 FFV.
It had been sitting for about 9 months and when I picked it up the miles to empty was less than 100 .
(meaning the fuel sensing units were operational)
so I put about 6 gallons into it and drove it a few times put in one bottle (treats 12 gal) of Chevron Techron fuel system cleaner.
drove it around some more.
I put 10 more gal
(avoiding the sticker shock of a full fill and not wanting to dilute the CT cleaner I put in)
Drove it around some more. All fuel sensing units were operational.
Decided that it could use a Trans flush at the Merc dealer and while it was there asked them to replace the fuel filter.
Got it all done and drove it around town and after running 3 start and stop errands the Check engine soon light came on.
Ran another errand and while idling in a parking lot the fuel gauge drops to below zero and the miles to empty indicated ___ .
So I turn off the motor and restarted it 2 or 3 times and the fuel gauge came back.
I drove it to the gas Station ( I was in the neighborhood) and filled it up (7.2gal).
I turned on the truck and the fuel gauge went straight to below zero and miles to empty indicated ___.
And the Check engine soon light was on.
Took it back to the Merc dealer and the fuel gauge had came back but the light was on so I asked them to read the code and clear the light and I was not paying for any of it.
They said it was illegal to clear the light.
But they would check it out.
I got it back and the CES light was off and the fuel gage worked.
I asked what the code was and they said fuel sensor.

They did say to put in some Cheveron Techron as the gas sometimes has high sulfur content and will cause fuel sensors to malfunction.

I had heard of this before and put in another bottle of CT .

I estimate at that point I had about 2 bottles in a full tank which is what the bottle recommends.
the fuel gauge went back to below zero and the CES light came back on.
So I just drove it that way .
I went around a freeway clover off / on ramp right hand turn at about normal speed (25 to 30 mph) and at the end of the turn the fuel gauge came back to 7/8 th s full.
CES light still on.
Next time I drove it the fuel gauge went straight to Below Zero.
And stayed that way for a few day and as the tank level got to about ¾ it came back on with the CES light still on.
I put in anther bottle of CT and drove for a few days.
Using my trip miles I decided to gas up at 180 elapsed miles with 12 gal to get me to ¾ tank.
Gage still ( at 15 mpg , I could use a stil) below zero.
CES light on and miles to E was ___
Put in another bottle of CT and drove it for a few days .
The gauge came back in between ½ and ¾ , CES light still on and miles to e fluctuating as I drive.
For a while there as I drove it was adding miles to empty.
Drove it for a few days.
Needing gas again at 152 elapsed miles I put in only 9 gal.
And another bottle of CT.
Gauge and miles to e still intermittent and stabilizing function at about ¾ tank.
Drove it some more.
At 169 elapsed miles I filled the tank with 14.9 gal
The Gauge responded immediately and the mile to e indicated a full tank 300 plus miles to e.
CES light still on.
I dove it some more
So after a few days the CEL went out by itself.
I didn’t think that was possible but it did happen.
Now every thing (Knocking on Wood).
Is all perfectly normal and operational.

 

[ShawnTRD]

So how many bottles of CT was that? I think it's cheaper and easier to replace the Fuel Sender.

 

[imp]

I have an '04 EB 4.0L. A few months ago, my fuel gauge dropped while driving, the SES light came on and I had the code pulled. The code said the fuel sending unit was bad. I recently had it replaced, but after driving less than 25 miles the SES light came back on - with the same old code. Replacement unit has been re-checked and verified as good, but the SES light remains on. Battery was replaced today (getting old anyway), but SES came back on after just 5 miles. Haven't been to the dealer, and my local repair guy now thinks there's something wrong in the instrument cluster and the wiring for the SES light. Anyone experience anything similar? Thanks.

Forgive my stupidity, but, SES must be "Service Engine Soon"? Is this type warning used along with, or in place of, the "CEL", "Check Engine Light"? Perhaps the optional "message Center" dash uses SES instead? imp

 

[BigRondo]

Forgive my stupidity, but, SES must be "Service Engine Soon"? Is this type warning used along with, or in place of, the "CEL", "Check Engine Light"? Perhaps the optional "message Center" dash uses SES instead? imp

Steve, a wise man once told me that there is no such thing as a stupid question, just stupid people that ask questions. You know I am just kidding. :

I believe that all of these acronyms are for the same purpose:

SES - Service Engine Soon
CEL - Check Engine Light
MIL - Malfunction Indicator Light

Basically, your engine is throwing a code, better get it fixed!

Hope all is well and you are applying plenty of sunscreen.

Take care, Rondo

 

[imp]

Hope all is well and you are applying plenty of sunscreen.

Take care, Rondo

Ha! Nephew begins a stint (USMC) tomorrow at Ft. Leonard Wood (MO), about 75 mi. NW of our place (now vacant!); yesterday it was -3 degrees there! Yesterday we swam in an outdoor pool here (AZ)........you should try completely retiring!!!! imp