2008 6.4 water in fuel light?

sam · February 13, 2008

I have this truck that came in and the customer is complaining about the wif light on, so i changed the fuel filters and drain the water seperator. he returns and says that is came back on, so like on the 6.0s i ordered the fuel header, while installing it i found a lot of gel/water in the lower part of the hfcm, cleaned it all out and replaced the header. drove it about 10 miles and no light, after the customer came and got it drove it 3 miles and the light came on, truck left but is coming back on thurs. have yall seen anything like this, can i get just the sensor or do i need to get the whole pump, have not seen any tsbs or ssms, or did i miss something.

hitechmech · February 13, 2008

starting to see this more frequently on new vehicles mostly (low mileage) and finding water in fuel tank. once fullt cleaned out no more problems

hitechmech · February 13, 2008

starting to see this more frequently on new vehicles mostly (low mileage) and finding water in fuel tank. once fullt cleaned out no more problems

sam · February 13, 2008

SO i need to drain the tank and clean the lines fill with known clean diesel to keep this from happening. the vehicle only has 14590 miles on it.

Jeff_ · February 13, 2008

Any software updates for the instrument cluster? I think 04's had a similar deal for which there was a reflash.

sam · February 13, 2008

when i get it back in here i will check for updates and see if there is water that will drian out of the seperator, Keep all suggestions comming.

LARRY BRUDZYNSKI · February 14, 2008

Sam the question I have does your customer usually have full tanks or partially filled where condensation can form in the tank? If it forms on the top of the tank it won't always drop down into the fuel, which could be the reason for the comebacks.

Keith Browning · February 14, 2008

Sam, I realize that this is a 2008 truck that you are working on but the basic concern is the same as prior Super Duty trucks. We have seen a lot of that cheesy build up in the water collection chambers which reduces the capacity of water it can hold. But removing the manifold and cleaning any contamination out is only a part of the repair. Inspect the WIF sensor for corrosion and sediment that could cause the light to stay on. The WIF sensor is serviceable on 6.0L level HFCM assemblies and I am thinking it might be for a 2008 as well. Please access and review TSB 06-22-12 for details on the procedures. The TSB wont cover a 2008 model truck and the part may not be applicable for a 2008 but it will give the general idea. Warranty will not cover a new manifold under a warranty if the sensor is avaialble... I imagine the same is true for a 2008 but if the sensor is not available then I guess you will need to replace the manifold.

sam · February 14, 2008

i have already replaced the manifold, the sensor is not in the manifold on the 6.4 like on the 6.0, i beleive it is at the front of the pump, but parts does no have a listing for the sensor,

Bruce Amacker · February 14, 2008

Yes, it's in the fuel pump housing on the front side just under the pump itself. It does not appear to be serviceable. /forums/images/%%GRAEMLIN_URL%%/shrug.gif

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Good Luck!

sam · February 15, 2008

thanks guys for all the help i will let you know what i end up doing to fix it when the customer brings it back.

Keith Browning · February 16, 2008

i have already replaced the manifold, the sensor is not in the manifold on the 6.4 like on the 6.0, i beleive it is at the front of the pump, but parts does no have a listing for the sensor,

As we can see by the pics the HFCM has been changed a lot! I have only drained the bowls on a couple but I did not snoop much. Good pics Bruce!

sam · February 16, 2008

I tried to get the housing and ford says that it is obsilete, so i ended up ording the pump so when it gets here i will put it on and then explore the old pump and housing before i turn it in to parts.

sam · March 10, 2008

ok its been awhile, but the truck came back finally, i replaced the fuel pump and reprogramed the pcm and ic. it has been about 2 wks now and no word of it. i think i fixed it.... we will see.

BrunoWilimek · March 10, 2008

TSB 07-24-04 still applies to these 08 trucks. It involves removing the mushroom vent cap from the fuel tank and replacing it with a length of hose. The vent cap is in a location that allows melting snow to pool and be sucked in as water into the fuel tank. This may help keep the problem from re-occurring.