Hope someone can help!!

Car failed its IVA on emissions at idle. Also am getting a lot of white smoke at start up.

Engine is a 1993 2 litre zetec running on a pre-pats EEC IV. I have checked fuel rail, inducton manifold vacuum which are Ok, have looked for air leaks as well and there does not seem to be any. I would like to check the fault codes from the three pin self test connector but do not know what fault code reader to buy. Can anyone advise what I need, or does anyone live near Faringdon, Oxfordshire who could lend me one for a couple of days.

Dave

Your best/cheapest option to read the codes if you don't have the original dash with the MIL warning light is a Gunson 77032
Do an ebay search on " Gunson 77032 Fault Code Reader " you should find one for less than £20

I don't think you will get much help from it as pre-OBDII fault codes will only tell you if a sensor is not working they aren't much help on emmissions. Grey smoke on start up suggests either valve guide wear or seal problems White smoke a head gasket.

I think you can do a blink test with a bulb on these as well.

Did you look at the lambda output at idle ? and check the lambada heater circuit?
The Lambda test in the IVA & MOT is not a test of the lambda sensor .

Diagnosing pre-OBD II emissions can be difficult.

Classic symptoms of an aging lambda sensor are it flat lines at idle but only starts to work as rpm is raised to 2000 when the extra heat of the exhaust gas wakes it up. The same applies if the Lambda heater element is not working, If the ECU doesn't see the Lambda sensor responding it will ignore it and run open loop and substitute default values which can be miles out particularly on a worn engine. What I suspect is happening is at idle the default fueling map is weak enough to cause incomplete combustion and occasional random misfires.

The lambda sensors on pre-1996 cars tended to have relatively short lives compared to more recently built cars which because of US Federal laws which required manufacturers to warranty emission system for 7 years can easily work for 10 years +.
On an OBD I car there is no real way to test lambda sensor output without an oscilloscope or graphing multi-meter although a DMM will show if the sensor is responding it won't show the speed of "switching" or the max & min range.

Did look at Lambda output at idle but it just gave me a lot on nonsense. I checked voltage output at idle with a simple voltmeter. Results were a little worrying voltage dropped to about 0.01 volts. I'm going to have to remove it and check heater etc. although this is a new sensor.