Mitsubishi Delica Owners Club UK™

[andyman]

It doesn't matter what size wheels/tyres or what ratio diff you have, because the speedo works off the tailshaft rotations. Definitely find a different way to check if your tacho is accurate. It is electronic, so plenty of fault possibilities.
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Andy C L300 Super Exceed - over 100 smiles per gallon!

[Google]

[peter_rookie]

hi Andy,
thx mate. just don´t get the hint....
if you say the speedo reads from the tail shaft you mean it would show same speed at same revs independent from gear ratio or wheels. that I understand.
but where does the tacho read the rpm from? what sensors or else can be checked?
I thought if I let them be read from the engine block and compare the reading from there with the tacho it should show if all is equal or not.
the calculation I did should be pretty accurate but understand the wheel circumference has no impact then. but the wheel sizes are not so far off from one another and without the wheel size can´t get to a reference point.
anyways following your logic it should just not matter which wheel size, rev/sped ratio should read the same. and here I am again being far off by ca 400revs at 62mph.
van is at the garage since yesterday so waiting for results....

[Lewis]

Speed sensor is a small electrical unit, on the passenger side of the transmission, slightly short of where the driveshaft is fitted in.
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[peter_rookie]

thx Lewis, I already replaced it and didn't change a thing.
but I read the speed from GPS and speedo and that is a pretty accurate match.
the issue is that the tacho read is too high. even in idle it is 900 while I think 600 to 700 would be normal.
so I am still puzzled about the revs and wonder what could cause the wrong output.

[Lewis]

Mitsu set the factory idle speed at 800rpm.
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Copyright is retained for all my photos. Please don't copy them without asking permission
Do not blindly go where the path may lead you. Go where there is no path and leave a trail that others may follow!
ルイス

[andyman]

So question is, what sensor are we looking for, crankshaft, camshaft or other? My L300 shows 3,000 rpm at around 115 kph/70mph in O/D, - if I can find a long enough flat, downhill or get the wind behind me!
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Andy C L300 Super Exceed - over 100 smiles per gallon!

[peter_rookie]

and here are the results....

Sensor reading vs Tacho
1000 vs 1004
1500 vs 1522
2000 vs 2018
2500 vs 2568
3000 vs 3060
4000 vs 4108

so, no real finding here considering the narrow margin from 2000 to 3000

so back to the riddle.
why does it rev so high???

[andyman]

You have now proved that your tacho and speedometer are reasonably accurate. Short of some anomaly in the gearbox, I cannot think of another reason why yours revs higher than others when locked up in overdrive. Both the L300 and L400 have 3+O/D gearboxes. On occasions, when accelerating gently at between 40-45mph, in my L300, mine will appear to shift into a gear between 3rd and O/D (I can feel and see a definite drop in the revs. As I continue to accelerate gently, it will perform another up-shift between 45 and 50mph, into O/D, and will stay locked in that for further acceleration, with revs increasing in proportion to road speed, unless I either accelerate hard (kick-down to 3rd) or ease off, when the torque converter unlocks at around 40mph, and the vehicle is then effectively coasting, with little or no engine braking effect. I can't explain this transient, fake 4th gear, perhaps insufficient pressure and torque to fully lock-up the torque converter? Slightly harder acceleration makes it accelerate in the normal 3rd gear until it drops solidly into O/D at 50mph or thereabouts. 50 in 3rd is 3,000rpm in the L300.
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Andy C L300 Super Exceed - over 100 smiles per gallon!

[peter_rookie]

thank you again Andy, you describe more or less what my Deli does.
also feel like having a ghost gear and this did not bother me as my Toyota Prado acts the same, very much the sane gear box 3+OD, Aisin Warner, there it is called 343F..
only that the revs in the Deli are higher. which I cannot figure out :-(
i was so hoping the tacho was off...
Anyways we are taking it on a trip the following weeks. will try monitoring the conundrum further.