Mr Locust

One for one drives and spotted!

Good to see everyone last Sunday. I've put low resolution copies of everything from my camera on an album here https://opa.cig2.canon-europe.com/s/cp/HVCQG2Fj4XK

http://flic.kr/s/aHsmi1pqjF Good to catch up on Sunday and to get the camera out in the Curborough sunshine. Low res shots of everything which was in focus are now on my Flickr account. Link above. As many members will know already, if you want larger files to make prints of your own just drop me a Blatmail. I do ask you to consider a donation to Midlands Air Ambulance in return. https://www.midlandsairambulance.com/how-to-support-us/ways-to-donate

The case I saw was on a friend's VHPD engined SLR. In that instance the car was fine under high load but idling and light/low speed running were really poor. When we moved the coil lead away from the crank sensor the issue went away. If there was a significant interference issue with the crank sensor it could affect starting.

Ensure that the centre HT lead hasn't been re-routed next to the crankshaft sensor at the rear of the engine otherwise interference can cause strange effects.

sredmile50 YHM.

Aeroscreens. YHM.

Rob J, Rob M, Delbert and Chris W. YHM.

I made it to Curborough for the first time in quite a while and in addition to catching up with some of the regulars, I managed to get T1/T2 shots of most competitors during the afternoon. Low res shots of everything which was roughly in focus are now on my Flickr account. https://flic.kr/s/aHskwDHpYW As many members will know already, if you want larger files to make prints of your own just drop me a Blatmail. I do ask you to consider a donation to Midlands Air Ambulance in return. https://www.midlandsairambulance.com/how-to-support-us/ways-to-donate

Short answer; by your own admission you buggered it up! Longer answer; the job of the ECU is to maintain the air fuel ratio, AFR. And you adjusted the AFR values of most of the load sites in your ECU maps, making them leaner than when the mapping was configured. Explanation: The fuel map cells deliver an amount of fuel which is based on how long the injector is switched on. For most Caterham/Emerald/DTH throttle implementations, the active cell of the fuel and ignition maps is determined by engine rpm and throttle position sensor, TPS. These are the axes of your maps when you access the calibration software unless your setup is calibrated to reference manifold air pressure, MAP (unlikely). The purpose of the TPS% in the setup is to give an accurate approximation of the airflow into the engine as the engine has no other airflow meter (as found in many volume production car fuel injection setups). At small throttle openings, a small change in throttle angle will give a massive change in the airflow into the engine. If you opened the throttle wider, then reset the TPS operating range and made no other changes, you made the whole fuel map leaner at every load site except wide open throttle or 100%TPS. You allowed more air for each TPS%, most significantly for the 0% (and near 0%), lines of the maps and provided the same fuel value. Assuming that the engine ran well before and that you haven't adjusted anything else, the best solution would be to reset the throttle stop back to the previous position and recalibrate the TPS. Even better if you noted the TPS values before you reset and reinstate these, then set the idle stop back to 0%. Any adjustments should be made by adjusting your cable and linkage and setup, not by rescaling the TPS. Hope this helps.

It is worth disabling the overrun fuel cut setting as it is a simple, "no parts" test to eliminate it as a possible cause of the issue (provided that you are confident in reprogramming the ECU). Depending on map settings and driving style, this setup can be prone to a lean misfire on resumption of fuelling after a prolonged overrun fuel cut event.

To clarify: Is this after a period of overrun at relatively high rpm?

Jon and Charlotte YHM

Robert Jacobs YHM

Low res album here. New layout gave some new angles.