1.9D TDC/Tacho sensor

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white exec
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1.9D TDC/Tacho sensor

Post by white exec »

Am now sorting out niggles (and essentials) on the newly acquired 19D Millesime.

One of the faults is a dead tacho.
Think I have found the thin cable that comes up from the sensor (pretty much invisible and inaccessible, down the back :( ) - it looks as if it connects at a brown 3-pin connector, just ahead of the firewall, and behind the battery.
Three cores from the sensor: red, green + screen
Two cores leading towards cabin: brown + brown

Have used a spare ABS sensor to send some cam pulley revs to the tacho, and can get the instrument to read 1000rpm.
However, the TDC sensor seems open circuit - infinity resistance reading between red and green, so presume the sensor is duff, or a broken connection down the back.
What should the d.c. resistance of a good sensor be?

The sensors all appear to be NFP, but which is the one for the 19D?
5918 75 TDC sensor
1920 C3 Engine speed sensor
(Presume 5918 80 Engine speed sensor is for the petrols.)
Last edited by white exec on Wed Oct 21, 2020 4:28 pm, edited 1 time in total.
Chris

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Re: 1.9D TDC/Tacho sensor

Post by rutter123 »

Plenty on ebay delphi units for about £20 seems to fit all XU5/6/7/9/11 and many more
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white exec
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Re: 1.9D TDC/Tacho sensor

Post by white exec »

Done a lot of trawling of ebay and other sites and catalogues.
Can find sensors for XUD9A diesel 1993-, but not for 1992.
Febi 37022 is an example - shown as ok for the engine, but not compatible for that year.

Can anyone help with a definite seller, or confirm the OE Citroen pt.no. (see above) so I can search on that?
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Re: 1.9D TDC/Tacho sensor

Post by IanE »

I have the same problem: the rev counter doesn’t work because the sensor needs replacing. I found these two sites which sell parts: https://www.rexbo.de/ and https://www.daparto.de
You define your vehicle, including the specific engine and then a list of parts are shown for that vehicle. Google can translate the site into English. One of the difficulties I found confusing was the difference between the speed sensor and the rev counter sensor, but I believe the rev counter is called a ‘crankshaft sensor’ or ‘Nockenwellposition’ (German). Searching for your vehicle and a camshaft position sensor results in
https://www.daparto.de/Nockenwellenposi ... ypeId=8909

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Re: 1.9D TDC/Tacho sensor

Post by white exec »

Ian, I think that second one (with the right-angle mounting lug) might be the wrong one.

A few problems in finding replacement diesel tacho sensor...

Even Servicebox, having entered the correct VIN, then goes on to list - under 'Sump' - Engine Speed Sensor "1905L and 16S". This isn't helpful, as 1905L is ambiguous, as I read it - petrol or diesel? [5918.80]

Next listed is "1905L" [1920.C3] Engine Speed Sensor. Again, petrol or diesel?

Lastly, TDC Sensor [5918.75] Could this be diesel?

A trawl through lots of aftermarket sites shows the first two are short/stubby sensors, with a right-angle mounting bracket.
The last one looks like the correct thing: long probe, to be mounted in the circular clamp.

Googling 5918.75 throws up a good few vendors, length quoted as 30/35mm, and resistance as 71R or 100R, and showing the long cylindrical body.

What could be relevant is that some of these sensors are intended as ignition timing/triggers on petrols, while others are used for tacho feed (diesels). Presumably important to get the right one.
_____

I'm likely to go for the 5918.75 for our XUD9A, but might not mount it in its original flywheel position, which is pretty well inaccessible. Will look at mounting it for operation by the camshaft (hydraulic pump) pulley, which runs at half camshaft revs. Flywheel, SFAIK, has two trigger notches at 180deg, so would fit the camshaft pulley with a 4-slot disc.

I did something like this on our old '89 19RD when I added a GTi tacho to that, with a small RS hall-effect sensor and an F-to-V driver added to the tacho (voltmeter) instrument, which worked well. Simply relocating the correct sensor for this one should be much simpler.
Chris

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white exec
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Re: 1.9D TDC/Tacho sensor

Post by white exec »

5918.75 confirmed as the correct one for the XUD, and NFP from Citroen.
Have ordered an FAE 79156 from Mister Auto, equivalent to OE pt.no.
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Re: 1.9D TDC/Tacho sensor

Post by markviney »

Hi,have only just seen this,may have a NOS 591875 will check tomorrow if you're still interested , thanks Mark

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Re: 1.9D TDC/Tacho sensor

Post by white exec »

Hi Mark,
Thanks for picking up on this. I'll let you know if I get stuck. Hopefully the replacement now on order will sort it . . . expected later this coming week.
Thanks again.
Chris

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white exec
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2003 Toyota RAV4 2.0 D4D
x 14

Re: 1.9D TDC/Tacho sensor

Post by white exec »

Sorted \:D/

Fitted the FAE 79156 from Mister Auto today, and the tacho now works as it should.
The item came boxed in an EFI-Bougicord carton, coded 79156F, correct dimensions, lead, connector etc etc.
d.c.resistance is 71R, in case anyone needs to check theirs; my old one had gone open-circuit.

Getting to the little bugger was a bit involved, as it was completely invisible, despite lights and mirrors.
Resorted to unbolting the hydraulic pump and its alu mounting block, and moving the pump aside.
This allowed the sensor to be seen, and unclamped.

Some ham-fisted 'erbert had, at some point, replaced the HPP pump, but made a right pig's ear of the cabling in that area, unnecessarily tangling and mis-routing speedo cable, sensor cable, throttle cable, etc., all of which is now sorted. Only the clutch cable took a sensible path. Hoping for a steadier speedo needle when the car gets on the road!

Handbrake cables
Yesterday replaced the handbrake cables with new. Old ones hopelessly stiff, although without any external wear.
Pushed a quantity of 5W30 down the new cables before fitting them.
Haynes' recommendation to stand on the footbrake to allow the handbrake self-adjust to operate worked out well.

Starter relay
Tomorrow, aiming to fit a relay between IGN sw and starter solenoid, to take the load off the IGN sw.
Will likely mount next to the glow-plug relay, and divert the existing trigger cable to the relay coil.

Radio/CD
Original door speakers pooped, so will replace with Pyle PDMW5.
Dash piezo tweeters have arrived, and have made up a pair of crossovers.
Will post some photos when the audio is all sorted.
Sony radio/cd HU is on the Xmas wishlist.:roll:
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Re: 1.9D TDC/Tacho sensor

Post by rutter123 »

To adjust handbrake cables stand hard on brake with engine running and pump handbrake a few times this should adjust it accordingly and bring it to less than 6 clicks on the ratchet before biting.
90 BX Tzd turbo 294k SORN undergoing major surgery
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white exec
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x 14

Re: 1.9D TDC/Tacho sensor

Post by white exec »

rutter123 wrote:
Wed Nov 11, 2020 9:24 am
To adjust handbrake cables stand hard on brake with engine running and pump handbrake a few times this should adjust it accordingly and bring it to less than 6 clicks on the ratchet before biting.
That's just what happened - worked a treat. :)
Chris