essb00 Posted December 8, 2020 Report Share Posted December 8, 2020 Good day, Cold start fires up easily (though lowest we get is +20°C ambient). Starting warm (ECT above 60°C) however, the engine is hard starting/flooding. I tried reducing the First Crank Prime down to 50% but still flooding. Engine by the way is 4A-GE 16V small port. https://drive.google.com/file/d/1oA9wwDWNHeQtW8GrBXH81ak-qqBaUEui/view?usp=sharing Quote Link to comment Share on other sites More sharing options...
Adamw Posted December 8, 2020 Report Share Posted December 8, 2020 Log please. Quote Link to comment Share on other sites More sharing options...
essb00 Posted December 8, 2020 Author Report Share Posted December 8, 2020 Quite strange that I can't replicate the hard starting now while logging. It has been happening the past days. I'll get back to this once I got something logged. Edit: Got one logged. Trigger errors appear whenever I release the start button. I'll also try to capture trigger scope whenever I catch it happening again. https://drive.google.com/file/d/1GsUwhFhxYjk_g7hKasJRN4OGG2lPYqJg/view?usp=sharing Quote Link to comment Share on other sites More sharing options...
koracing Posted December 8, 2020 Report Share Posted December 8, 2020 The only 4A I've messed with so far was pretty sensitive on the arming threshold of the trigger signal - it's possibly that is the cause of your trigger error counting going up. I notice your timing while cranking is 23 deg - maybe drop that down a little. If it is flooding, then it should improve if you hold the throttle open some amount while cranking (providing more air to offset the extra fuel). Once the wideband appears to go active around 46 seconds the closed loop is pulling 15% fuel out - have you tuned the warm idle fuel values on your fuel table already? A lot of these tables in the cold start are offests or percentage adders based on the base fuel table. Making a change there may yield more affect than adjusting a trim based on erroneous base table values. If you know what cold requires to start good, you can always add more down lower on these cranking and priming tables to increase cold start values back up to what they are now once you have hot start working as it should. Quote Link to comment Share on other sites More sharing options...
Adamw Posted December 8, 2020 Report Share Posted December 8, 2020 All of the extra PW during cranking is coming from the shape of your fuel table. Remember your MGP is near zero when cranking, it is unlikely your cranking VE is as high as 90%. Also as koracing pointed out even in the idle area it seems it is at least 15% too rich already. Typically I would start with a near flat VE in the first two columns - but you may even need to taper it down towards 0MGP. Your normal idle PW looks to be around 2ms, but you have 4X that going in during cranking. Im not sure if this really is the cause of your flooding issue as most engines are happy with quite a bit more fuel during cranking, but it is somewhere to start. I would also set your accel fuel deadband higher. It is not activating much in your log, but it is borderline just kissing it at normal smooth idle so it is going to catch you out sooner or later. Bump it up to 1 or 2 will do it. Quote Link to comment Share on other sites More sharing options...
essb00 Posted December 9, 2020 Author Report Share Posted December 9, 2020 @koracing I've just bumped the Trig 2 arming to 0.4v as I saw quite a lot of noise from trigger scope during starting. The cranking ignition angle as I understood should have been pulled from the ignition table, so I am unsure why it seem to get the ignition idle target 23° instead. Warm idle is already tuned (quick tune, with some point adjustments I manually made), maybe my previous log was just not long enough and it has not stabilized yet. It starts quite easily without a miss after being left sitting for a while (I really couldn't say cold when it is sitting 30°C ) @Adamw I've just dialed the VE lower in the cranking cells you have marked. I guess I'll need to do more trials (hopefully less errors). Maybe there's a chance engineering can add a 'flood clear' option? With conditions like while cranking whenever you press the throttle more than a set percentage, it will turn off injection & ignition. Just a wish.... Revised tune file:https://drive.google.com/file/d/1bsBKegcLY1a6ppx920cVfkmJcQmnNSFz/view?usp=sharing Log - Cold start to warmhttps://drive.google.com/file/d/1V1k5nbQgS1rzTy6Gwv-XB8sV2lyu2OEN/view?usp=sharing Log - Warm starthttps://drive.google.com/file/d/1RuGHKv0gIJOlmw6V-fA78KlL0nZBiJc8/view?usp=sharing Quote Link to comment Share on other sites More sharing options...
koracing Posted December 9, 2020 Report Share Posted December 9, 2020 It should be possible to set up a virtual aux to trigger the stop function based on throttle and RPM to clear flood, but I agree it would be nice to have this as part of the TPS settings. Quote Link to comment Share on other sites More sharing options...
essb00 Posted December 9, 2020 Author Report Share Posted December 9, 2020 @koracingGreat idea. Thanks. I've just made one. Quote Link to comment Share on other sites More sharing options...
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