Thread: Disco Black spark plugs?

Hi Boxer

I just had a quick look at that site and what they mean is they tested the non cat map (what we have in Oz in one form or another), the cat map (yanks) and the TVR map. They all have the 14CUX computer but the fuel mapping is different on the chip to suit the vehicle/application.
So our computers are fine. All you need to do is fit the sensors and wire them into the existing computer.
Also need to change the tune resistor to select the USA tune to enable the sensors.

14CUX diagnostics-Good news/bad news.
Fuel economy 3.9 with O2 sensors

There are a few but I had a post in one of PhilipA's threads that had photos of my install but can't find it anywhere.
PhilipA did a pdf of his install that can be sent to you. It should probably be in the Files/Projects section but isn't at the moment.

I'm pretty keen on fitting O2 sensors now, yet right at this point in time I'm having a bit of luck with it. Having checked the CO voltage before it was very high at 3.4V from memory, so that explains the 9:1 AF ratio yesterday. So I got to work on it last night and adjusted it down to 1.1V and the car seemed to be running nicer.

This morning I rigged up an Autometer AF gauge I have sitting patiently waiting to go on my turbo car and welded up a probe similar to the ones on dynos. The new idle mixture was around 15.3 ish. Having taken it for a drive it was doing about 14.6 on light throttle accel, 15.6 on cruise and no worse than 11.4 on hard accel.

Will fill up the tank tonight and see if I can get a rough idea of L/100 in the next two days.

Might have to wait off on that Microtech afterall.

Then again, we had discussed installing one that does fuel and timing... then accidentally slipping a turbo under the bonnet.... Maybe one weekend when I have more time

Did this thread just get hi-jacked?

I was just wondering what could cause my plugs to get so black.

Oh well.:

Boxer,

I was kind of interested in heading down the route of retro-fitting lambda sensors, but since I've had a play with the MAF I can't see there is any noticeable affect on the low range driveability (assuming you're not a long way out like yours were). I don't believe there is any effect whilst moving as the ECU will be operating on a fixed map.

So, what are the benefits? Emmissions and fuel economy? At AU€0.23/litre economy isn't an issue in Qatar and am I going to make so much of a difference to global warming by fitting them??

Ben

Big Guy,

Are the spark plugs black "sooty" or "wet"?

Sooty: running too rich or ignition system problem. Could be the MAF - do you have a cat? Could be the O2 sensors.
Wet: Is it oil or petrol?

Ben

Originally Posted by big guy

Did this thread just get hi-jacked?

I was just wondering what could cause my plugs to get so black.

Oh well.:

3 days is a long time to leave a post---
but all of the above info should be usefull if you are trying to repair it.

Originally Posted by big guy

Did this thread just get hi-jacked?

I was just wondering what could cause my plugs to get so black.

Oh well.:

Sorry mate, will revert back to the other thread about idle probs.