VDO GUAGES

[Jozi]

If there's anyway I can help with the m52 end of things let me know. I might be pulling the engine from the car and putting it in a stand over xmas.

[Grrrmachine]

When it's out, can you look at the oil filter housing and let us know if there are any blanking plugs on there?

[DanThe]

No blanking plugs on M52 housing, but you can fit the standard adaptor into the oil switch location and use a temp sender and twin function pressure switch. I have done this in the past on S50's but dont have any pics unfortunately.

[Grrrmachine]

Thanks Dan. I thought that was the case.

So here it is people, the definitive guide on VDO Gauges. What they do, how they work and how to get them into your E30:

http://www.e30zone.net/e30zonewiki/inde ... VDO_gauges

[j2b]

Thanks Dan. I thought that was the case.

So here it is people, the definitive guide on VDO Gauges. What they do, how they work and how to get them into your E30:

http://www.e30zone.net/e30zonewiki/inde ... VDO_gauges

Well appreciated thanks

[capri_rob]

Just won a set on Ebay

Bit more than I wanted to pay buy hey ho its Christmas

Will do a proper write-up with pics when I get round to fitting them

Dan might need your help

[j2b]

Just won a set on Ebay

Bit more than I wanted to pay buy hey ho its Christmas

Will do a proper write-up with pics when I get round to fitting them

Dan might need your help

I had a touch with mine at £20 but they are getting a bit scarce

[TouringMatt]

I got a spare banjo bolt and dripped/tapped the end for the temp sender, removed the oil pressure switch, replaced it with a braided line and used a t-piece to mount the gauge sender and pressure switch on the inner wing.

Seemed to spend on fortune on it too

Looks messy, kinda fits with the theme of the rest of the car lol

[DanThe]

I was thinking exactly the same, mount the temp sender in the banjo bolt for the oil cooler take off
Then just an adaptor for a twin function pressure switch

[daimlerman]

Sensors fitted very neatly for me.....

[capri_rob]

Going to order the T piece for this hopefully tomorrow.

Looking at the pressure switch thats there currently it appears to have one of the square plastic fittings ( like on the fuel injectors and blue temp sensor ) for the wiring rather than just a single spade connector ( which is what the VAG pressure sender has for the tell-tale light on the dash ).

Means chopping the OEM plug off by the look of it - Am assuming its just a single wire inside and I can just put a spade connector on it ?

[Grrrmachine]

As the Wiki article states:

"At this point, you should have a loose plug on the engine loom from where you removed the Oil Pressure Switch. Take a small length of wire (2-3") and add a male spade connector at one end, and either a female spade or ring terminal at the other. Use this new wire to connect the Oil Pressure Switch plug to the WK terminal of your Oil Pressure Sender, so that your dash light works properly."

You should be able to fit a normal spade terminal into the existing loom plug no probs, so you don't have to chop it.

And let us know how the T-piece fits; are you getting one of the LMA ones?

[capri_rob]

So the OEM plug on the loom for the factor pressure switch is just a normal female spade connector hence the "extension" with the 2-3" wire with a male spade connector on the end ?

Cool - I hadnt pulled it off so just assumed it was the same inside as the blue/brown temp sensors etc.

Yes getting one of the LMA T pieces - will probably order it from demon tweeks.

[Grrrmachine]

It is the same plug inside as the injectors, but there's only one pin (the other side should be blank) so yes, it'll work like a female spade. Might need a bit of electrical tape bodgery to hold the new wire in there tight, but that's better than cutting the loom.

If your T-piece fits, I'll be ordering a load in; I've got 5 sets of senders and gauges here

[capri_rob]

I'll see what I can come up with and take some pics.

[appletree]

All I'm saying is that when I used a 150c sender with the normal Audi vdo gauge (other other vdo gauges might be different) my Gauge read 130 at normal operating temp and with a laser temp gun it was running just over 80c at the filter housing as you might have expected.

Here's the link to the thread about it

http://the-corrado.net/archive/index.ph ... 32b0f111c6

Well done getting the temp sensor, there special 0-180c rather than the normal 0-150c which as I found makes you gauges read 130c at 90c.

There not to dear from Audi though. pt # is 049 919 563B if any ones interested.

I've fitted mine in the vents to, but went for oil temp, oil pressure an boost

Appletree the set I'm looking at says it comes with the 0-150c sender - why would that give an incorrect reading if that sender and gauge came from the same car ? Surely if it gives the correct readings in one car it will do so in another ?

[daimlerman]

Going to order the T piece for this hopefully tomorrow.

Looking at the pressure switch thats there currently it appears to have one of the square plastic fittings ( like on the fuel injectors and blue temp sensor ) for the wiring rather than just a single spade connector ( which is what the VAG pressure sender has for the tell-tale light on the dash ).

Means chopping the OEM plug off by the look of it - Am assuming its just a single wire inside and I can just put a spade connector on it ?

If you examine my photo on the previous page,you will see that I extended the original oil pressure switch wire by about three inches,it's the bit of white wire going to the bottom of the T piece.Not sure if my original oil pressure light switch is a BMW part,it has a tag on it for a standard push on female connector which is protected by that rubber boot.I cut off the spade female and soldered that bit of white wire on,with a suitable connector at the 'ther end.

[capri_rob]

Just ordered the T-Piece & Adaptor from Demon Tweeks for mine. Will update this thread with how it fits with the standard Audi sensors and pics.

Now just got to sort out putting the wiring in place and we should be good to go

[TouringMatt]

Just ordered the T-Piece & Adaptor from Demon Tweeks for mine.

Same place i got mine from, surprisingly helpful when i ran into problems

[capri_rob]

Have ordered based on the part-codes on the Wiki so we shall see if they're right !

Just got to get some copper crush washers now.

[Grrrmachine]

All I'm saying is that when I used a 150c sender with the normal Audi vdo gauge (other other vdo gauges might be different) my Gauge read 130 at normal operating temp and with a laser temp gun it was running just over 80c at the filter housing as you might have expected.

I've got four different 150c gauges here, and a batch of sensors arriving this week. I'll perform a basic test (boiling water with a mercury thermometer!) and see what Ohm-readings those senders give, and how it affects the gauges.

[capri_rob]

As per my earlier posts has anyone fitted gauges/senders which were removed from the same car ( rather than buying them separately ) ?

Can't see why they would show correct readings on one car and incorrect readings on another if they are a matched pair.

The temp sender I have does not seem to have any markings on it although I was assured by the seller that it came from the same car the gauges were out of. Time will tell I guess

[capri_rob]

Ok super quick delivery of the T piece and adaptor from Demon Tweeks - ordered yesterday afternoon and arrived this morning.

Have encountered a small but niggly issue.

The "long" T piece is fine and will enable the chunky VAG pressure sender directly on the side.
The only issue with this is that the thread on the VAG sender is quite long, and even with a copper crush washer in placeit probably blocks off 50% of the hole that the oil will flow through to get to the end mounted temp sender.
Using as thick a crush washer as possible may help but you'd probably need 3 of them stacked on top of each other to space it out enough for unrestricted flow through the T piece.

Second problem is that the "short" adapter piece is about 3mm too short for the standard VAG sender unit - again looks like this will need at least 2 x crush washers on top of each other to space it out.

I may just order the longer one.

Pics to follow so you can see what I mean.

[Grrrmachine]

If you look at the bottom of the pressure sender, it's a tiny pinhole that serves as the oil channel. Considering oil pressure can go up to 6 bar if needed, then as long as there's a small gap through the middle of the T-piece, then that's all that's needed.

If the oil channel in the T-piece is reduced to 50% diameter, that should be more than enough to get hot oil to the temp sender at the end too.

And the "short" adapter is what's converting the T-piece end hole from M12 x 1.5 to M10 x 1.0, correct? Are you saying that the temp sender therefore won't screw in fully to the adapter?

[capri_rob]

Heres the pics :


This is the "short" adapter - the temp sender has the shorter of the 2 threads and even that won't go all the way in ( it will however go in the side of the T piece without interrupting the oil flow )



This is how its supposed to go together yes ?



With the pressure sender in the side you can see how much of the thread is exposed to give unrestricted oil flow through the T piece - would need at least 2 probably 3 crush washers to fill the gap.



With the sender screwed fully home you can see how restrictive it is.

I have sent the short adapter back to DemonTweeks as they have said they can exchange it for the longer one.

As the pressure sender has the longer thread I think it may make more sense to put that in the new "long" adapter in the end of the T piece and the temp one in the side.

Then got to figure out the wiring on the gauges.

The original VAG loom is still in place which includes a relay ?

The voltmeter is easy but on the oil gauges there is a +, - anda G wire on each one

Tracing the wires from the temp gauge I'm guessing + and - are just power supply and earth and "G" is for gauge ? - I.e the feed from the sender ? as the "G" wire on the gauge loom corresponds with the offcut on the sender ?

Sorry if this sounds a bit longwinded but I want to get it right without shorting the gauges out

[TouringMatt]

Wiring sounds about right, dont know about that relay?

I ditched the loom that came with mine and made my own,

+ = ignition switched 12v to all
- = earth to all
G = sender from engine bay

Im sure that if you put 12v to the gauge terminal is just reads max

I didnt use crush washers on my senders (not OE ones though) as they have a slight taper on the thread, just used some PTFE tape on the threads

[capri_rob]

Ok think I've figured the Audi Loom out as follows :



The largest white plug in the pic is the main Power feed :

To this plug
Red/Blue stripe appear to be Power from the car loom to the cigarette lighter
Brown = Earth
2 x Grey with blue stripe = feed for illumination of 2 x bulbs with instrument lights - connect to existing car illumination feed
Thin grey/brown stripe wire to relay ?? Igntion on feed to relay ?
Black/Blue stripe - ignition on power feed to gauges

Longer wire at bottom of pic can be connected to your existing E30 Cigarette lighter & illumination
Secondary bulb off this loom can be used for ashtray illumination

Beige plug :

Green with black stripe - to Temp sender in engine bay
blue with white stripe - To pressure sender "G" terminal

The only one I'm struggling with is the wires to the relay.
This appears to only control the illumination so not sure if its actually needed although Audi must have put it there for a reason.

2 x Grey/Blue stripe wires feed the cigarette lighter/ashtray bulbs
Grey/Red stripe wire feeds all 3 of the Gauge bulbs
There is a single grey/brown stripe wire which goes to the relay and terminates at the big white plug. Not sure on this - possibly provides power to the relay when the ignition is switched on ?

[capri_rob]

This relay is doing my nut in

Power for the instrument lights comes in from the car loom to the 2 x Grey/blue stripe wires in the main white block.

These go into the relay ( power in when lights on )

Coming out of the relay grey/red stripe sends power to gauge lights

So the third relay terminal grey/brown stripe is this an earth ?

Whats the point of the relay ?

[Grrrmachine]

Relays are easy, but that's not what you've got there. The big chunky plastic thing is a slave dimmer unit, and most of the wiring around it is pointless; you're much better off pulling the loom of the gauges and making our own, simpler connections between the sender terminals and the bulbs.

Robbed from a Golf forum:

Wire colors on the VDO gauge harness are:

Blue / black - Switched 12V (terminal 15)
Brown: Earth (terminal 31)
Green / black - Oil temperature signal
Light blue / white - Oil pressure signal
Grey / blue - Illumination
Red / blue - cigarrette lighter feed (not needed)

Cut off the white plug, not required on a Golf, some also have a lighting relay fitted, you can cut this out it 's not needed.

Locate a switched 12V supply, and connect the blue / black wire.
Found mine at the ignition switch and spliced in.

Locate a good earth, and connect the brown wire.

The voltmeter is now operational, as are the oil pressure and temperature gauges, though the latter 2 need a signal

[Grrrmachine]

As for the senders, that all makes sense to me rob. I'm surprised that the short adapter isn't long enough to accept the temp sender, but that's the only problematic part as far as I can see. Shame though, and I'll make a note of it in the Wiki. Might even get onto LMA (who make the part) to let them know.

Don't worry about the pressure sender restricting flow though; with 2-5 bar the oil will have no problems getting through that hole to the temp sender.

For the actual wiring, you're pretty much spot on. The + and - on the gauges is just power and earth respectively, then you run a single wire from the sender to the G pole on the back of the gauge.

Out of curiosity, what's the length of the threaded part of your temp sensor?

[capri_rob]

The threaded part of the temp sender is 9mm, the threaded part of the pressure sender is 12mm.

Thanks for the explanation on the "relay" thats not a relay !

So if I fook it off the lights will still dim anyway via the existing E30 headlight switch.

Does it make much difference which sender goes in the side and which one in the end ?

Starting to think if the "long" adapter will accommodate the full thread of the pressure sender I'll put that in the end and the temp one in the side.

[Grrrmachine]

Senders:

Makes no difference how you place the senders. If you consider how small the hole is on the pressure sender, and how high the pressure is in the engine, then that one will work as long as it's got a sealed oil supply, no matter how small.

The temp sender is just a heat resistor; it'll change temp just because the whole lump of metal (t-piece, adapter etc) will get hot. It will never be 100% accurate, because it's outside the engine, but it'll be good enough.

But if your 9mm temp sender doesn't fit into the adapter though, the 12mm pressure sender definitely won't

Wiring:

Link all your bulb live wires together, and feed them to the bulb in the ashtray. Then they'll dim with the headlights.

[capri_rob]

But if your 9mm temp sender doesn't fit into the adapter though, the 12mm pressure sender definitely won't

I have sent the short adapter back to DemonTweeks as they have said they can exchange it for the longer one - cost is the same - it went recorded delivery today so hopefully if they get it tomorrow and send the long one straight away I'll have it for Saturday

Fingers crossed that it will accept up to a 12mm thread depth and all will be good.

Thanks for the wiring info - will do pics as I fit it all up

[Grrrmachine]

Ok, I've appended the data in the Wiki so that the "short" adapters are no longer recommended. If the long adapters don't work either then I'll hunt for an alternative.

Sorry for that confusion

[capri_rob]

Not your fault - the "short" adapters may be OK for aftermarket senders - until a few more people do the job we won't know.

Demon Tweeks customer service were fine about exchanging it anyway.