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Fuel injector cutoff upon throttle close

Posted: Sat Oct 15, 2005 8:50 pm
by smracing
How do you tune the point at which the injectors shut off and come back on? I am having a problem getting a smooth transition from part throttle to closed throttle coast down? When I let out of the gas, say coming up to a stop the car gets really jerky.

Another problem that has arisen is when I am at WOT and go to shift I let off the gas for a split second and the roll back into the throttle when I let the clutch out, the engine kinda hesitates (like the injectors have turned off) then it comes back on and continues revving like normal.

All this started after I changed the Wideband settings to take advantage of my wideband gauge. My AEM outputs 0-2v so I set up the S300 to take feedback. I will post the file as soon as I get back to my laptop.

I have the throttle tip in fuel trim set at 15%.

Posted: Sun Oct 16, 2005 10:14 am
by Hondata
Is your TPS adjusted to read 0% with the throttle closed? What MAP sensor are you using?

Posted: Sun Oct 16, 2005 5:55 pm
by smracing
Yes my TPS is set to zero and I am running a stock MAP sensor right now. This just started after I started tweaking with the Tip in fuel trim to get the part throttle pinging to go away. That solved that problem but now I am getting the wierd fuel cut at WOT shift points.

Posted: Mon Oct 17, 2005 9:49 am
by Spunkster
What did you set the throttle tip in to? What size injectors are you running? Can you please post the calibration?

Posted: Mon Oct 17, 2005 6:08 pm
by smracing
I am running an AEM wideband gauge outputting 0-2 volts. Here is the tune. The engine is a D16Z6 with stock injectors (for now), turbo w/450s shortly.

Posted: Tue Oct 18, 2005 9:45 am
by Spunkster
Post a datalog of the problem you are describing.

Posted: Tue Oct 18, 2005 1:16 pm
by smracing
Can't. First my laptop battery died and my new one isn't here yet.

Second, I can't get my datalogs to give anything more than a couple of sensor readings and RPM. Check out this test datalog.