ERR5198 - Which aftermarket one to get?

[Dalamar]

Has anyone had any success using a Britpart or Allmakes AFM unit in their car? Otherwise TVR Parts now stock a UK made version but it’s more than double the price.

I’d appreciate your thoughts.

[spitfire4v8]

I prefer to use a good genuine used part .. but then I would say that because I have a massive stock of good used secondhand parts from the emerald conversions .. The tvr parts one hopefully will be a good one, but avoid the cheap ebay chinese stuff, the outputs seem to vary wildly.

[Dalamar]

Hello. Could you please let me know how you decide on the good ones? Is it by Rovergauge values or electrical responses at the AFM connector?

[Dalamar]

Oh what a difference an AFM makes!

Joolz from Kits and Classics got in touch and very kindly supplied me with proper Lucas badged unit that made the world of difference to my car and its long term lambda values.

It went from -100% long term on both banks.



To this, around +30% both banks with the short term oscillating around zero.



The engine is smoother on initial start up, runs smoother around town and the emissions results from the MOT last week were around 50% of those measured last year.

Fast Idle
CO 0.026% (pass is <0.200%)
HC 74ppm (pass is <200ppm
Lambda 1.000 (pass is between 0.970 and 1.030)

Natural Idle
CO 0.014% (pass is <.300%)

The only thing I haven't been able to properly gauge is the electrical switch on test that Blitz mentions where the voltage to the glue/green wire with respect to earth red/black is 0.3V within 2 seconds of ignition on. I saw my multimeter rise to ~0.5V and drop to <0.4V in about 4 seconds. My multimeter isn't the fastest and I haven't got a scope yet.

Anyway, I'm very happy I've got my long term lambdas in a sensible region now and I can say that the over fuelling issue with my car is now sorted.

Many thanks to Joolz for the AFM and Blitzracing (from other earlier Rovergauge topics) for their help and teaching me a lot about using Rovergauge to diagnose my car.