SkyEyes Posted January 10, 2022 Report Share Posted January 10, 2022 I'm having an issue where my acceleration enrichment is causing my injector pulsewidth to vary quite a bit, resulting in incredibly rich idle. My current settings are: We have discovered that with the throttle fully closed, PCLink still shows .4-.5 for TPS. I re-calibrated the TPS just to make sure that it was properly set, but that didn't change what we are seeing. For some reason, acceleration enrichment is going crazy. I'm not sure if I'm understanding the settings incorrectly, but I thought it was set so that it was within the deadband threshold. I'll attach the datalog and current file as well. If I deactivate acceleration enrichment, or change it to MAP, my pulsewidth smooths out immediately and lambda comes up. It is also worth mentioning that with the engine off, TPS will read 0.0, but as soon as the engine starts I'll see a reading between .2 and .4 for TPS. 01072022 Rev 0.pclx PC Datalog - 2022-01-10 7;57;01 am.llgx Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 10, 2022 Report Share Posted January 10, 2022 If accel enrichment is set to TPS mode it is triggered by TPS delta (i.e how fast the throttle is moving). Your TPS Delta at idle is upto around 19 so set your deadband somewhere above this. Note this is unusually high (more typically less that 1% delta at idle), it may suggest there is no cable free play, or throttle is not sitting on the stop, or there is a bad ground or similar. But increasing the deadband to more than 19% will fix the immediate problem. SkyEyes 1 Quote Link to comment Share on other sites More sharing options...
SkyEyes Posted January 10, 2022 Author Report Share Posted January 10, 2022 Thank you Adam. I'll apply the change and see what it does. I'll also thoroughly inspect the throttle cable and double check TPS indexing on the throttle body. Could a bad ground be the cause for seeing an immediate change to TPS as soon as I start the engine? When I built the harness I grounded the TPS to pin 24. I attached another short log of engine start. PC Datalog - 2022-01-10 10;55;53 am.llgx Quote Link to comment Share on other sites More sharing options...
SkyEyes Posted January 10, 2022 Author Report Share Posted January 10, 2022 For testing purposes I removed the TPS from the throttle body, but left it connected to the harness. For some reason I am seeing TPS percentage go from 0.0 to between 0.3 and 0.5 once the engine is running. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 10, 2022 Report Share Posted January 10, 2022 It sounds like you've got a ground offset coming from somewhere, like sensor ground is coupled to chassis ground somewhere or similar. It may be ok to just set the deadband high enough to ignore it but it is hard to know whether that is going to make it too insensitive to actual throttle movement. You will have to try it and see. Quote Link to comment Share on other sites More sharing options...
SkyEyes Posted January 10, 2022 Author Report Share Posted January 10, 2022 5 hours ago, Adamw said: It sounds like you've got a ground offset coming from somewhere, like sensor ground is coupled to chassis ground somewhere or similar. It may be ok to just set the deadband high enough to ignore it but it is hard to know whether that is going to make it too insensitive to actual throttle movement. You will have to try it and see. Could it be because I have pins 25 and 34 grounded at the same point? I discovered the problem. It had to do with what I tied into the sensor ground circuit. My mistake but it is fixed now and my TPS percentage remains at 0.0 unless I depress the gas pedal. Quote Link to comment Share on other sites More sharing options...
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