Back on the road but paranoid

Yesterday I resurrected my gelled TDI.

I recharged the battery (Do I need to replace it after it got run down? Is a recharge adequate?)

While the battery was charging I added more fuel I had warmed up inside the house and added some additive.

In the engine bay I replaced the fuel filter and re-installed the engine cover. (I noted that the engine cover does a good job of shielding the injector pump from wind. It may make a more significant difference in cold weather than I previously thought.

After all this a few cranks and I'm back in business.
Now I am paranoid.
I logged my commute with the VAG monitoring fuel temp (Group 7?) and it steadily rose the whole trip. The outside temp was 38F. Fuel temp rose from 20.7c to 32c

I still have questions about the automatics fuel cooler. Does anyone else question why a device that cools fuel in the return line a good thing?
I imagine that warm fuel returning to the tank and filter keeps the system warm. What good is a 4" x 10" radiator on the return line under the front passenger seat. I am resisting an urge to cover this thing or bypass it in winter. Does anyone have any insight?

Also has anyone confirmed that new fuel senders have larger check valves than the original ones?
When I couldn't start the car the problem was definitely between the tank and the fuel filter.

BTW I rented a GEO Metro while I was down and feared for my life in this thing. What a drastic difference in solid feel and quality between these cars.

Torque: We missed you this weekend at the GTG...

But we did ALL watch your appearance on Chronicle!

I'm glad to hear that you've got your car back... I would just double dose on antigel...

Or better yet, try to find some Power Service Arctic Express Antigel... I've got some of the PSAEA for biodiesel and I'll let you have some if you can't find it anywhere else. This stuff is super concentrated and needs only a 1:500 additive ratio. It's supposedly recommended for B20, but does wonders on B100 and one can only imagine that it must have an even bigger effect on Bzero.

Also, I would INSULATE your FUEL filter... I ran a thermocouple to my filter and I've found that the filter cools considerably while at highway speeds as compared to in town driving. If that doesn't work, then I would look at bypassing or insulating that fuel cooler. If you need or want some help, let me know...

I could not attend the GTG as I was out of town. even if I were here my car was still dead at the time. It is pretty heavilly dosed with addatives right now and I ordered the primrose products (Powerflow 509) which should arrive soon.

I thought about insulating the fuel filter but am concerned I may limit heat gain. Perhaps some sheilding from wind would be better but for now I am leaving my VAG hooked up and monitoring all my driving.

Bypassing the fuel cooler seems like a no brainer in cold weather but I am very curious why it is there to begin with. I don't want to mess with any clever VW engineering just becasue I don't understand it.

I thought about insulating the fuel filter but am concerned I may limit heat gain.

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<font size="2" face="Verdana, Helvetica, sans-serif">How so? I'm talking about wrapping insulation around the outside of the filter to keep the fuel inside warm, and therefore ungelled. I'm willing to be that 90% or more of the cases of "gelling" are simply fuel filters clogged with wax crystals from fuel that is below the cloud point but still above the gel point...

The T-valve system will still function as before, and the valve should align to the tank even sooner than before since the closed loop fuel system will retain more heat.

I don't want to mess with any clever VW engineering just becasue I don't understand it.

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<font size="2" face="Verdana, Helvetica, sans-serif">I agree with you here... that's why I recommended this as a second level modification...

I'll give the insulation a shot. I have some meant for engine compartments I bought a while back. The temperature is dropping again so if there is a problem it will come back.
Rather than bypass the fuel cooler I may just wrap it up to protect it from wind. I'll continue to get some information on why automatics need this thing and not manuals.
While the automatic has been fine I really wish I put my foot down and did not compromise on the transmission with my better half. I'd be enjoying better mileage and less maintenance.

Story goes that the auto's use smaller injectors generating more heat in the fuel. Hence the fuel cooler. What hasn't been proven/disproven is whether the fuel cooler has an internal bypass function when cold.