Need your help about these exhaust test results obtained during VRT test (Hot engine idling at 900 rpm):

CO = 1 to 1.5%
CO2 = 14.9
O2 = 0.53
HC = 142
lambda = 0.987
Temp = 70 degree C

vehicle is sapphire cosworth 4x4 red top standard engine and T3 turbo, MSD (blackpool) stage 1 chip, mongoose exhaust, K&N air filter, 2 bar map sensor, 071C spark plugs gapped 0.7mm, Bosch 044 rewired fuel pump, 3.5 bar fuel pressure, - 31 acuator, standard fuel injectors.

Are these figures correct ? I suspect they aren't. A previous test, some 2 years ago showed CO at 2.61%. Since then the only changes made were a new alloy radiator+ intercooler internal cleanup/flush + oil change from mobil 1 15/50 to Titan race pro-s 10/50.

Whats your verdict?

Many thanks for your valued advice.

 

I'd say the reading look fine, was it boosting ok with the old intercooler as the old one could of had a pin hole cause it to suck in air causing the higher CO, also was the last test done at the same engine temp as a colder engine gives off more CO

 

Ginger turbo,

Intercooler was never replaced just internally flushed clean of oil residues tested for air leaks, none of which were found, and re-installed back in place. Oil temperatures are in fact cooler by some 10 degrees C and this I attribute to replacing the factory radiator with a 50 mm alloy radiator. Somehow I have a feeling the CO level is low. I asked the test station operator about this and he remarked that the lambda value was perfect, and that this value was the main parameter showing the quality of the air fuel mix.

I'm open to more advise

 

forget the intercooler change

you could take off the throttle body pipe and it would make no change as there is no fuel metering via the intake system from turbo/air filter and its all done via the MAP sensor and the water temp sensor in the head

you need to check their values with a ohm meter before you do anything

check at the sensors, then at the ECU incase its got a shagged loom

hope the above makes sense

 

if you are not too sure, ring Martin @ Zqodi racing

i think his number is 00356 21430482, thats the one i have in my phone anyway!

regards Sean

 

I'm not planning to do anything yet, not before I get confirmation that the exhaust gas values are wrong or right

 

we have hairy balls, not chrystal ones!

yes they look fine on a PC screen

its purely dependant on the values your car is giving out!

it may have a split in a exhaust gasket giving more oxygen to the emissions probe when the values are worse that seen

unless you know what your car is seeing to/from the sensors no point doing anything else to be honest

 

Ok, i'll will be checking the Ohmic values of MAP sensor and corresponding coolant temp sensor and see if they are realistic

 

Those values are fine mate. drive and enjoy.

 

Hi Stu, thought you would intervene in this matter sooner or later
thanks for putting my mind at rest. Am very happy with your chip, engine performs without a glitch

many thanks to all PF members who contributed