Random hesitation with new exhaust

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cannondale27 · #11 Post by **cannondale27** » Mon Dec 08, 2008 1:23 pm

Being rich or lean can cause a hanging idle.Usually its rich.But could be things like IACV not closing or torn boot.A throttle cable adjusted to tight can also do that.

SlOoT · #12 Post by **SlOoT** » Mon Dec 08, 2008 3:14 pm

Thanks, I will look into all of those things. The offset is 0.75, is it safe to go lower?

Thanks for the help

cannondale27 · #13 Post by **cannondale27** » Mon Dec 08, 2008 3:43 pm

Try going higher like Kdeal said.Thats real low .75 I bet its real lean at idle.Start at 1.0 adjust by .05's.

claas900 · #14 Post by **claas900** » Mon Dec 08, 2008 4:28 pm

I got this from the harrymoto web sight and have found it to be very close for setting the offset. "set the idle to 2100 and then note the throttle position. Adjust the offset by .1, then set the idle again and note the throttle position. The offset setting that gives you the lowest throttle position to maintain 2100 RPM is the optimum idle setting. You might go back .1 richer from there to get a more steady setting"

MyCannibal · #15 Post by **MyCannibal** » Mon Dec 08, 2008 11:32 pm

Yes...I was going to say idling too fast...should be around 2100.

SlOoT · #16 Post by **SlOoT** » Fri Dec 12, 2008 8:45 am

Another thing I noticed. When the engine is cold and I start it, it idles at a throttle % of 4.7. But that numbers becomes lower and lower, and the idle screw is not backing out.
Once the choke is at 205 the throttle% stops to go lower and remains at 3.6%. I already switched the TPS, and also switched the ECU. It does seem to idle nice now around 2200.

SlOoT · #17 Post by **SlOoT** » Fri Dec 12, 2008 11:36 am

I checked the IACV, it's working.

I now swapped the throttle body, including the TPS and IACV. Did a throttle calibration.

It now idles at 5.2% when the IACV is closed. But it was at 6% when the engine was cold and I did not notice the idle screw backing out...

SlOoT · #18 Post by **SlOoT** » Fri Dec 12, 2008 1:02 pm

Another thing I noticed. I set the idle at 2200, throttle postion is 5.4% when engine is hot.
I let it cool down a bit and did not touch anything, and the throttle position is now at 6%.

It seems that the throttle % becomes lower when the engine gets hotter. But the idle screw remains at the same postion. Is that normal?

Thanks

SlOoT · #19 Post by **SlOoT** » Fri Dec 12, 2008 1:27 pm

Ok, it idles good. Good throttle response. Good performance wide open.

I think I found the spot were the problem is.

When in 1st gear, I let it roll on idle. Then I increase the throttle to about 10-15% and keep it a that spot, then the RPMs increase and at a certain RPM (3000-4000) it wil start to act crazy, RPM goes up and down very fast. When I give it some more throttle the problem is gone.

cannondale27 · #20 Post by **cannondale27** » Fri Dec 12, 2008 1:49 pm

Maybe a lean spot in map or TPS bad at that point?