S3C Lambdas

[Marc C]

Long story short... Car has lambda wiring which has been chopped off way back in the loom for some reason, which I plan to re-instate as afaik the ECU is correct for an S3C, but I have no idea which sensors are correct, all I know is that it should be a three wire sensor with and 18mm thread. Does anyone know the correct original make and part number for these sensors?, or should I just go with the 'universal sensors' that google throws at me.

Also, the car came with S/S manifolds which were for a non-catted car (ie. the long ones) I was going to drill and boss these just past the three into one bit. Any reason why this shouldn't work?

ATB

Marc

[Marc C]

Yes it's definitely as S3C and has the original engine in it, I think Neil (whose comfy seats you now sit on I think , which reminds me I still need to find some seats!) had issues as well, as the car had an assortment of spares when he got it inc. ECUs and manifolds and AFMs. What I think happened was that whoever owned it before Neil has tired to de-cat it and made a bit of a hash of of it, and not only tried to remove the cats but also re-instate the AFMs and an earlier ECU, which explains the home brew wiring.

As of now I have installed the correct ECU (one for a Lambda car, at least I think I have) and am in the process of reinstating the Lambda wiring which has been cut out near the grommet, as the car came with S/S manifolds from a non-cat car I was going to drill and boss these...

Problem is, as the car didn't have any lambdas when I bought it and i'll be honest the only S series car I've ever seen in the flesh is mine one, I have no idea which sensors are the right ones... and google doesn't help by only giving me these 'universal' style sensors on my searches.

If the universal ones are the right ones then great, as they are nice and cheap, but I suspect that originally it was a Bosch or NGK or something

[Marc C]

AutoAndy said:

Not sure if you could just add onto a non-cat manifold or not...it would. Make sense that you could.

That was what I thought, as long as there are roughly in the same place ie. just past the three in one pipe union, the only variable I'm not sure of is how far into the gas flow the sensor should sit, never having seen an actual S3C manifold it hard to be certain but based on the piccys on here it look like it should be no problem, would prefer not to have to splash out on another set of manifolds and decat pipes.

[Marc C]

v8s4me said:

Seen this post?

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

Last entry.

Thanks for the link, alas I already have XJS seats ... but I don't like um

Really want either Chimeara seats or good original S seats, in black or maybe that dark red colour

[Marc C]

Thanks LawrieS for the info, gave me a good starting point, so I spent the morning on the internet and doing a bit of ringing round instead of working, and so far I have worked out that the original lambdas were 3 wire Bosch 3000 series (258003122 and 258003123), no idea why they have different numbers for each bank, but these are hard to find and are not listed under any Ford engine that I’ve looked for…

The difference between a three wire and a four wire is the earth, three wire sensors have two white heater wires which are not polarity specific and a black signal wire, four wire sensors have an additional grey earth wire, and can be used if you run a dedicated earth. The three wire ones earth through the exhaust apparently.
Sierra’s have (25800)3097 listed for 1988-89 cars, which changes to 3294 for 89-93 cars, Granada’s list as 3294 for 1992 then switch to four wire ones post 92.

Best info site I found was http://www.lambdasensor.com/main/ford1.htm

Spoke to a chap on the phone who said that I could use the ‘universal’ style ones, but that they are a bit crap and don’t last anywhere near as long, Bosch ones are rated for 100,000kms. He also reckoned that the differences in part numbers were down to the loom attachment clip supplied as opposed to the actual sensor itself.

So I did a google for the part numbers and one of them threw up tvrgit’s website (Feb 14) who has already been there and done all the research, he used 3294 sensors, be interesting to know if he has had any issues and if these are now an genuine alternate part.

[Marc C]

Not of any use to me 'cause I don't have any at the moment, but chap I spoke also pointed out that if I was have idle troubles, running rich etc that the problem may be that the lambda sensor is not earthing with the exhaust via its body due to corrosion and the ECU is dropping into a default/limp home setting and that a clean up of the threads can sort it out.

[Marc C]

tvrgit said:

I don't post here so much these days, for various reasons, including offering advice that was ignored among apparently random guesses, until an "expert" said the same thing.

Well in that case 'many thanks' for confirming the details of the sensors, I shall start shopping for them, well at least I will when I get paid as they're not exactly cheap.

As a side note, sites like you own, the threads on here and various other sites that people put time and effort into really are a godsend for real amateurs like myself... when you read a manual that you know is written in english but may as well be in mandarin for all the sense it makes... the ability to post a question, read your blog, refernce tvrsseries.com amongst others makes it possible to actually have a go at doing a job yourself which is half the fun (the only fun in my case) whereas without these resources, I at least would find it near impossible!

ATB

Marc