Irish Mini Owners Club

put new cat in it new o2 sensor n it failing test , any ideas not drawin air and nearly all sensors in engine changed

I have had same problems with 2 spi cars
Had to swap ecu from a doner car that had passed And worked .

Any modifications at all to the car?
What readings are you getting?

low idle 1050 rpm oil temp 83 deg CO.84 HC810 PPM
high idle lambda 1.06 CO .56 HC 74 PPM
MO MODS ONLY MANIFOLD , BUT IVE MOVED THE LAMBDA SENSOR INTO Y PIECE SO IT READIN ALL OUTLETS

Get a map sensor it is in the manifold at the side and new water temp sensor. There the other components that control emmisons on MPI mini.

Also check the wiring going to each sensor

all changed already wiring also fine took loom apart and continuity on tester all the way

I'm also been having great trouble getting my 99 through the emmisions test, it is very doubtful that the ecu is to blame. After changing sensors, cat, manifold, wires, hoses, hg and stem seals I now suspect that air is getting past worn exhaust valves and guides of a poorly reconditioned head. What mileage is yours? Any blue smoke? Have you changed temp sensor? There is also dipetane to consider.

2000 miles on engine , tried diptane still no use , think a litre a fuel and a match il sort it , it a money pit that needs to stop

2000 miles from new?
Your low idle should be around 850rpm which suggests air leak.
a bit more history needed about your car, PM me if you want.

maybe the Lambda probe is in the wrong place and or angle?
that could be sending the wrong readings back to the ECU and mucking about with your readings

Your low idel is too high so the main thing is to get it down to 850 rpm. A high lambda means the mixture is too LEAN so maybe an air leak. One I came across before was the servo hose not sealing right. Remove the hose put some grease around the end and push back in. If your using a K&N air filter element you may concider fitting a standard one for the test. How well the lambda sensor has been repositioned may be an issue.

Ooh am I thankfull I have a carb engined car

I going try the new sensors when they come , if they fail il buy a donor car for ecu , ive tried everything on it .;(

CLUBMANGT wrote:Ooh am I thankfull I have a carb engined car

Except on a below freezing winters morning.

I'm not a fan of replacing sensors without some evidence of them being faulty, have you had the car checked for fault codes?
Most sensors can be checked by measuring there resistance hot and cold.

woody wrote:I'm not a fan of replacing sensors without some evidence of them being faulty, have you had the car checked for fault codes?
Most sensors can be checked by measuring there resistance hot and cold.

second that...