Fuel gauge issues

[Polly Grigora]

ric355 said:

Here's an image of the connetions.


I can confirm that the 0-250 ohm range is correct for the gauge, with 0 ohms being full and 250ohms being empty. I can say this with absolute certainty because I have previously tested my own original gauge using the resistor method I described earlier.

You sir are a star

[Polly Grigora]

Tyre Smoke said:

I did sort if do that. Stuck my multimeter on ohms and read the sender unit. Original was goosed, well, ok to halfway, then a broken wire. The new one was great, 6 ohms empty, 190 ohms full. But we now know it should be 190 ohms empty, zero (or rhereabouts) full.

But and it's only a small but but matters much

New sender reading 190 Ohms for empty doesn't match the above information

This tells us that in the future having replaced the gauge with a known fully functioning gauge the reading will be incorrect

Or am I missing something?

[ric355]

Polly Grigora said:

But and it's only a small but but matters much

New sender reading 190 Ohms for empty doesn't match the above information

This tells us that in the future having replaced the gauge with a known fully functioning gauge the reading will be incorrect

Or am I missing something?

As I said earlier, you need to match the sender to the gauge spec. 190ohms is only 75% of the range so if the sender was working the correct way around you would only get a gauge range from full to 1 quarter.

(Not sure if the new sender you are referring to is the one that appears to be the wrong way around or a second new one from a TVR supplier).

I still think it's unlikely that your gauge is faulty but we'll find out in due course.

[Tyre Smoke]

No, on the dace of it, you're not. But to clarify...

I thought my sender was faulty because I took it apart and discovered a broken wire or two on the windings of the resistor. So I bought a replacement from ebay not realising at the time that the TVR sender worked in reverse to most 'normal' fuel set ups. So I've ordered a new TVR sender from Racing Green. I know this will be correct when it arrives.
In the meantime, to confuse things further my gauge was not doing consistent things. Testing it would confirm it working correctly, five minutes later it was doing the opposite. I concluded for the sake of £40 I'd buy one from Ebay. So, in short, having confirmed the wiring between tank and gauge is all good, I will fit a known good gauge and sender this weekend.
Hopefully that will be an end to the saga.

[Polly Grigora]

Tyre Smoke said:

not realising at the time that the TVR sender worked in reverse to most 'normal' fuel set ups

But does it work in reverse to 'normal'?

Information from ric355 proves the gauge and sender to be the same as the majority are

ric355 said:

Here's an image of the connetions.


I can confirm that the 0-250 ohm range is correct for the gauge, with 0 ohms being full and 250ohms being empty. I can say this with absolute certainty because I have previously tested my own original gauge using the resistor method I described earlier.

[ric355]

Tyre Smoke said:

not realising at the time that the TVR sender worked in reverse to most 'normal' fuel set ups.

I think 0 ohms = full is the most common one and therefore what I would consider 'normal'.

[Tyre Smoke]

Ah, okay then. The one from ebay being reverse of that.

[Gladers01]

Tyre Smoke said:

Ah, okay then. The one from ebay being reverse of that.

If you filled the tank up and used the reverse sender from ebay presumably the gauge would read somewhere between empty and one quarter full if everything else is in working order, and as you use the fuel the gauge would move towards the full position, how green is that ?

[Tyre Smoke]

Exactly. A useful anti theft device

[Tyre Smoke]

Replaced the sender unit and all working properly.

The sender needed a bit of fiddling with, it was showing ¼ tank when the sender was 'empty' so had to adjust the stop with a pair of pliers. Other than that, 10 minute job.

[LucyP]

Which is what a TVR specialist would have taken. You started on 7th February. It's now the 21st! And three pages worth of posts on here. Sometimes taking it to a garage is the best option.

[QBee]

LucyP said:

Which is what a TVR specialist would have taken. You started on 7th February. It's now the 21st! And three pages worth of posts on here. Sometimes taking it to a garage is the best option.

I say this regularly on PH.
Never before in the field of human conflict has so much been said to shoot one person down in flames.

[Tyre Smoke]

Except I enjoy working on my own car. I like the satisfaction of completing a job. I also work, eat, sleep and have a life.

Why should I take my car to a 'specialist' when there is nothing specialist about a V8 TVR?

You might consider three pages of me using trial and error to be a waste of time, but I have saved m6self a fortune and learned a lot in the process.

Quite honestly your condescension is boring. This is a car forum for enthusiasts. It started as a TVR centric forum for the sharing of fixes and ideas. You don't like the thread I started on my fuel gauge? Don't read it. I received a lot of useful and practical advice and pointers along the way. Not only was my sender u/s but so was my gauge. OK, so it cost me £20 for a sender from ebay that was no good, but I'm sure I'll find a use for it somewhere sometime. But even allowing for that, it's cost me the grand total of £80. How much 'specialist' labour and parts would I have got for that?

[ric355]

Tyre Smoke said:

Except I enjoy working on my own car. I like the satisfaction of completing a job. I also work, eat, sleep and have a life.

Why should I take my car to a 'specialist' when there is nothing specialist about a V8 TVR?

You might consider three pages of me using trial and error to be a waste of time, but I have saved m6self a fortune and learned a lot in the process.

Quite honestly your condescension is boring. This is a car forum for enthusiasts. It started as a TVR centric forum for the sharing of fixes and ideas. You don't like the thread I started on my fuel gauge? Don't read it. I received a lot of useful and practical advice and pointers along the way. Not only was my sender u/s but so was my gauge. OK, so it cost me £20 for a sender from ebay that was no good, but I'm sure I'll find a use for it somewhere sometime. But even allowing for that, it's cost me the grand total of £80. How much 'specialist' labour and parts would I have got for that?

I wouldn't rise to it if I were you. Just take a look at that person's post history, and it will tell you all you need to know.

[Tyre Smoke]

Thanks mate. And thanks for your previous input. Very helpful!

[Polly Grigora]

Nice fix, well worth the effort

[SwanJack]

Tyre Smoke said:

Except I enjoy working on my own car. I like the satisfaction of completing a job. I also work, eat, sleep and have a life.

Why should I take my car to a 'specialist' when there is nothing specialist about a V8 TVR?

You might consider three pages of me using trial and error to be a waste of time, but I have saved m6self a fortune and learned a lot in the process.

Quite honestly your condescension is boring. This is a car forum for enthusiasts. It started as a TVR centric forum for the sharing of fixes and ideas. You don't like the thread I started on my fuel gauge? Don't read it. I received a lot of useful and practical advice and pointers along the way. Not only was my sender u/s but so was my gauge. OK, so it cost me £20 for a sender from ebay that was no good, but I'm sure I'll find a use for it somewhere sometime. But even allowing for that, it's cost me the grand total of £80. How much 'specialist' labour and parts would I have got for that?

Well said, my sentiments exactly and Tthe process you went through will help others !

[TarquinMX5]

Tyre Smoke said:

Except I enjoy working on my own car. I like the satisfaction of completing a job. I also work, eat, sleep and have a life.

That's obviously where you've gone wrong

[Tyre Smoke]

Dammit!

[Tyre Smoke]

Small update. New sender went in, gauge ( the old one) appeared to be working fine so I left it. Yesterday, went to Bristol and back, bloody gauge reading full all the time.
This morning, swapped the old gauge for the new one and working perfectly. Except the logo on the new gauge is different to the others. I wonder if it comes apart so I can swap bits over...

Well, with alot of careful prising, the silver bit will come off the front of the gauge. And yes, with a small flat blade screwdriver, bits will swap over. So, now I have the new gauge with the old face that matches the other gauges and it's working perfectly.