Help with High CO2

[eng530]

Having a problem with high CO2, about 9.5 at 2500 rpm and the lambda reading out of the limits of the gas detector on the low side.

Have tried...
fitted new o2 sensors
tried replacement air flow meter
tried replacement ecu
fitted new temperature sensors
fitted new spark plugs

but still get the same readings. Car runs fine otherwise. We think it is getting too much fuel but struggling to make any progress. Car seems to flood itself sometimes.

Not sure if this is common fix but relay on the fuel pump was bypassed long ago to overcome a previous problem but dont have full details why....

Any suggestions

[blitzracing]

It could be a failed be a failed catalyst matrix, but you need to take a couple of steps backwards in your fault diagnosis, and dont throw parts at it on the chance that you may fix it. Firstly beg borrow or steal (or even buy) a fault code reader and plug it in .

https://delta.securesslhost.net/~shenglt/catalog/i...

It should throw a fault code for chronic over fueling, if the ECU cant keep the mixture within tolerance. It wont throw a code if it just runs rich once in a while however. Also get a test meter and measure across the black (+ve) and white (ground wire) from the Lambda sensors on both sides with a warm engine. Easiest access point is to pull up the extension plug / cable on each side under the fuel rail. You should see it cycling 0 to 1- 1.2 volts at about 1/2 second intervals at idle. It should continue to do so as you take the engine to 2500 rpm, (and beyond) although the switch rate will change. If its stuck at 1 to 1.2 volts on either side it shows over fueling, and the ECU should be showing a fault code. Generally over fueling can be caused by over high fuel pressure, missing vacume to the fuel regulator, over high AFM output,(its not got a Torque flow fitted has it?) or wrong fuel map.

Ive done lots here: http://www.g33.co.uk/fuel_injection.htm

[bigdods]

Where are you located ? I have a fault code reader you can borrow if anywhere near silverstone.

[eng530]

Thanks for the offer but we are up near Inverness. Not very handy to pop in past!

[bubblehead]

I your going past Glasgow anytime soon you can borrow mine.

Bubbles

[TVR Stef]

When I got my car I found the lambda sensors wired up in reverse. I guess this might have happened when the clutch was changed by a previous owner. Might be worth checking the wiring against the bible.

[haircutmike]

Mine failed at fast idle.

Took it for a thrash and let it fast idle for about 20 mins untill piping hot just before the test and it "just" passed.

HTH.