Various Engine Sensor Woes

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bmouthboyo
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Various Engine Sensor Woes

Post by bmouthboyo »

Background Info
My van was originally a DG but in the early 90's a previous owner was on of the first people to put a GTI in a T25. As such I have a 1.8 Golf Mk1 DX Kjet GTI engine.

At present the dash red light flashes continuously, oddly unless I turn on the headlights then it stops!?!

Anyway I wanted to check I have the correct senders to work with my instrument panel, which I assume is the original DG wiring.

I have 6 sensors

Number 1: On the rear of the ending head

Image

I have no idea what this one does but I assume its the oil pressure switch. I am not sure how to test if this is what is giving me the red flashing light issue?

No 2: On water flange on rear of head
Image

Another unconnected one which I assume is water temp of returning radiator hose?

No 3: On a hose junction on the front of the head


Image
Image

This one seems to work. My temperature does sit about 3/4 of the way up however so wanted to check its the correct sensor. All it seems to say on it is 'B310'

No 4: On the top of my oil filter housing
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This is not in use and seems the top is broken. I am hoping to replace and use with some Audi VDO gauges I sources a while back

No 5: on the side of my oil filter housing
This one is unconnected and seems to be leaking a little. I assume this is another oil pressure switch from the Golf. I hope to replace this with an oil pressure drum in future for use with VDO gauges.

Image

No 6: Under coolant tank
Unconnected / no wires to connect to it ? :( Wouldn't the DG originally have had this wiring?

Random

I traced the wiring from No 3 Sensor to a junction box and it connects here:

Image

The other wire next to this just connects to an earth! Is this right?

Summarise
So basically what sensors should I be using?
What should I do about the coolant presence sensor?
Any ideas why using the headlights will make the red light stop flashing.
How can I expect the red light to act when not using a coolant presence sensor?

Sorry for the long post but I like to be thorough :ok
Last edited by bmouthboyo on 02 Aug 2017, 19:35, edited 2 times in total.
1983 Autosleeper Trooper - 1.8 Gti Conversion

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Mocki
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Re: Various Engine Sensor Woes

Post by Mocki »

Can't answer the bit about that senders are what , I don't know .....

However , Red flashing coolant light I can tell you this....


The flashing red light in the temp gauge has two functions ....
1. If the gauge is above 3/4 and it's flashing it means over heating
2. If the gauge is below 3/4 and it's flashing , it means low coolant in the header tank.

If it's say low coolant , and you can see the header tank is full to the brim ( not the number plate flap top up tank) then it's an electrical issue , and simple fault diagnostics will need to be employed !

Red flashing coolant light self tests when you switch the ignition on and then goes off ......

The system is very simple....
The headertank ( the one in the engine bay ) should always be full to the brim, and the top up tank ( behind the number plate flap) should be full to the max mark when cold. When the engine is up to normal running temp the coolant expands and is pushed into the top up tank, when the engine cools down the coolant is sucked back into the header tank

Headlights stopping the coolant light could be as simple as a bad earth, but normally it works the other way round, and headlights or brake light make them flash ..... someone will be along soon who knows more for you .....
Steve
tel / txt O7947-137911
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bmouthboyo
Registered user
Posts: 428
Joined: 29 Apr 2009, 17:11
80-90 Mem No: 9396
Location: Bournemouth

Re: Various Engine Sensor Woes

Post by bmouthboyo »

What about when the light is flashing the whole time?

My van is an early 83 DG, would it have had the coolant sensor? I have never seen any wiring for this and cannot find any cut wires leading to the main loom.

Also on a side note, should i swap to using my Gti engine Oil Pressure switch as the requirement will be different I guess?

Thanks
1983 Autosleeper Trooper - 1.8 Gti Conversion

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