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I have a weird problem because I know the source but I can't determine what is going wrong. All of this is still without a finished tune on my Haltech Pro 2000.
When I rev my car above 1500 RPM and hold my throttle position, my engine will jump up and down about 500RPM. This happens in more than one spot of the map and I've gone through the areas to roughly make sure the transition is smooth between the cells on both the ignition and fuel table.
This problem did not occur before I put in my idle control valve, which is 3 wire running BAC main and slave. The idle works great in this case and sits at about 70% open. When I open the throttle it only cuts back to about 50% and I get the erratic RPM. I have my trace screen open showing the idle position and I don't see it fluctuating with the RPM so I don't understand what is causing the unstable RPM
I will get a log file tomorrow, but I have attached my tune. Is it as simple as a bad idle valve? Its not a new one.
Thanks ahead for the help!
If you're seeing the ICV dropping to 50% when the you're opening the throttle then it's likely something in the software as it doesn't have a position sensor in a 3 wire ICV. If you get your trace and a copy of your map someone should hopefully spot the cause.
Thanks for the response Chris!
I'm please to say I managed to solve it! Depressing to admit the reason.. Turns out my tps was slipping on the throttle shaft so it wasn't registering tps position.
These thing happen, at least its an easy fix