missing lambda relay? help please

[Stick Insect]

I'm off on Sunday on a 2,600 mile rally around the French Alps. I have got the car running again after many years. I was told by the rolling road technician the car was running lean. It was suggested by a friend that the 12volts may be missing from the lambda sensor. I've not had time to check yet. The car was bought as a damaged repairable 21 years ago and so I don't know if anything is missing.

The panel in front of the drives knee shows the relay in position 12 to be for Lambda sensor. no relay is present.
Should one be there?
what is the number please?
I have attached a photo, the holder referred to has a purple identification band.

[Error404]

Hey there! Long time

I had this relay holder empty on my 7A too.
Have you checked the fuel pump and injectors are delivering correctly after all those years?

[newsh]

Hi David

Long time no see

I think the car is a 7A right?

Welcome back and glad the car is back on the road

[S2central.net]

Those stickers would be in fiction section of any decent library. There is no lambda relay in the S2 but there is a specific fuse for the lambda heater. Check fuses 24 - 28 as I cannot remember which one it is.

[Stick Insect]

Hi error 404 ( Alex if I recall?) I hope my spare engine is going well!, Hi john and Paul,
thanks for the prompt reply, I will have to have a look at the sensor and check if there is 12 volts there. I have fitted the undertray for the first time in 21 years of ownership. just in time to need to take it off.
The car has done only 21,000 from new, the MAF and injectors have been cleaned
The car is a coupe Quattro 20V. 7a engine.
I'm entered in a rally called the November Sun Run http://www.15-50ac.org/
It's my 4th year. The last three years have been in my Morris Minor. the run back from Monte Carlo Last year included 530 miles cross country in 14 hours. I though I'd cheat and do it in a real car this year.
Still got to fit heated recaros on Gold Mk3 electric seat brackets ( need modifying)
sort out a dragging rear caliper
fit aftermarket cruise control.
and most importantly fit the radio!.
any thoughts on the weak running appreciated. A new bosch Lambda sensor has been fitted.

[S2central.net]

If new lambda probe doesn't fix things, then it's either MAF or fuel pressure. Could be a weak / old fuel pump despite that amazingly low mileage. I would need to hit the library to find any useful data on the 7A engine diagnostics.

[S2central.net]

Lambda heater fuse is number 28 on the 7A but I doubt that is your problem

Did the RR Man say you had lean running at cruise and part throttle or just wot ?

[Stick Insect]

Thanks Paul,

the fuel tank and pump is out of Clive A's old S2 as it didn't fit his short Quattro project. I have a new pump and will give that a try.

The rolling road technician mentioned the lambda was slow to respond. which still could be down to a lazy fuel pump...
Good suggestion.

David