TDI mpg vs engine temp

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lloydy
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Re: TDI mpg vs engine temp

Post by lloydy »

I don't think it is a exact science when they open. I know someone else runs at 87, I'm at 90 and your at 95.
Time is a drug. Too much of it kills you

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lloydy
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Re: TDI mpg vs engine temp

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Success! Cut in the adapter and T3 sender, i ended up cutting back the plastic sheaf on the wires to the tdi sender and removing the two wires from 2 and 4 on the plug and fitting them in the T3 plug. The adapter fits in with just about no free space on a syncro due to the tank, 2WD will have a lot more space i would have thought.
Image
Image
gauge and scangauge now in perfect harmony
Image

Thanks to Simon for the help sorting out the parts needed for this.
Might not seem a lot to some people to have the gauge reading right, but i feel happier knowing up is 90 :D
Time is a drug. Too much of it kills you

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keith
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Re: TDI mpg vs engine temp

Post by keith »

Nice work Lloydy....

My ahu runs cool.....I'm sure my vag com figs were around 79......only bit I'm not sure about is what you had to do with the wiring.....

Its got me interested... :ok
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lloydy
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Re: TDI mpg vs engine temp

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Hi Keith, if you mean the wires i fitted into the T3 sender, its quite straight forward....
If you find the coolant temp sender, mine was held in with a clip on the coolant manifold on the head, you will see it has 4 wires going into it, two are for the ECU so it knows how hot/cool the engine is, and two go straight to your temp gauge in the dash. From what i have found heard, the resistance isnt the same as the T3 gauge. When you pull the plug off the coolant sender you will see it is marked 1-4, numbers 2 and 4 are what go to your gauge. I removed them from the plug and fitted them to the T3 plug/sender. Now the gauge reads right
Instead of removing them from the plug, you could find the original wires from the jx loom which are probably in that black box in the corner of engine bay and extend them to the new T3 sender, but i think it was neater what i did.
Doing this on it's own won't make your engine run hotter, you most likely need a new stat.
If you end up doing it and want some more pics, just ask
Time is a drug. Too much of it kills you

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Re: TDI mpg vs engine temp

Post by jed the spread »

How you finding the MPG so far Lloyd?

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lloydy
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Re: TDI mpg vs engine temp

Post by lloydy »

Nothing to report yet, only driven it a couple times to the shop and back. This Salisbury weekend should give me some idea. To be honest though, reading up on it you really don't want a cool running engine if you want it to last. Lots of nasties apparently, condensation in the oil for one.
The gauge was surprisingly out, with the tdi sender just to the left of the led was 77 degrees(which was the temp I used to run at), now I'm using the T3 sender, 77 is only just out of the white section
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Re: TDI mpg vs engine temp

Post by Cableguy »

Early figures suggest 38 mpg for mine:-)

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lloydy
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Re: TDI mpg vs engine temp

Post by lloydy »

is it tomorrow you pick it up? Or was it today?
38mpg is good, i'd be happy with that, sadly 4WD eats a few mpg's. Just out of interest, do you know what temp you are running at? And did he fit a new stat?
Time is a drug. Too much of it kills you

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Re: TDI mpg vs engine temp

Post by Cableguy »

Picked it up on Monday. Temp sat at 72 to 78 all the way home. Mainly driving at 65/70. Is also running bigger nozzles. Have a couple of things to fix still:-/
Reversing light stays on all the time, not sure why?? and glow plug light flashes. Forums say this means a fault on the ecu, but the scan guage shows no faults.
Doesn't affect the performance and goes out when I press the brake pedal.

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lloydy
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Re: TDI mpg vs engine temp

Post by lloydy »

Glad you got it at last beggers belief that you still need to fix bits. Sounds like you haven't got a new stat in as your running pretty cold.
For the reverse light, maybe the switch is jammed?
Strange with the flashing light, have you got the pedal switches fitted? Could be a bad brake switch?
Time is a drug. Too much of it kills you

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Re: TDI mpg vs engine temp

Post by Cableguy »

Yes Will check the brake switch. Seems wierd that it doesn't throw up a code though.
Re the stat, the donor car ran at a constant 90 so not sure why it's now running cooler. Will get a new stat anyway, there's very little antifreeze in it, so may as well sort that at the same time.

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lloydy
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Re: TDI mpg vs engine temp

Post by lloydy »

He sent me off with no antifreeze, so feel lucky you got some! :lol: as for temps, the gauge on the donor car is designed to read 90 from 70-100 (or there abouts) so you can't really use it as a accurate reading
If you want to try my brake switch your welcome to pop over, I'm off work next week
Time is a drug. Too much of it kills you

Cableguy
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Re: TDI mpg vs engine temp

Post by Cableguy »

Awesome, thanks. I have a couple of days free next week, I'll whizz up and have a butchers :ok

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lloydy
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Re: TDI mpg vs engine temp

Post by lloydy »

No worries, I'll be out on Monday, rest of week I'm around
Time is a drug. Too much of it kills you

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Re: TDI mpg vs engine temp

Post by Cableguy »

Just noticed I have a missing wheel nut too.
FFs

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