How do you prevent accel pump at idle?

[05plsrt4]

Since i've been tuning my car myself, i noticed that it was very hard to control the afr's at idle. After some searching found that the accel pump was adding fuel while sitting at idle. I've changed pretty much every setting but am unable to prevent it from doing it.

Is there one graph that i forgot to change?

[nutz]

Quote: Originally Posted by 05plsrt4

Since i've been tuning my car myself, i noticed that it was very hard to control the afr's at idle. After some searching found that the accel pump was adding fuel while sitting at idle. I've changed pretty much every setting but am unable to prevent it from doing it.

Is there one graph that i forgot to change?

check your TPS settings, there should be a threshold (% of tps change) that allows the accel pump to activate, if your AFR is hard to control at idle you may also want to try to adjust the o2 FB update rate if its too fast (a larger number will slow it down) it will over shoot and constantly hunt

[05plsrt4]

I had issues with idle....and recently only idle. I did what chuck said and changed my tps adjustment so that it never read 0....now i have a whole list of problems....but mind you the car idles pretty damn good.

I can watch all the fuel modifiers and when it goes really rich the accel pump is "activating". But when i change the trigger or any of the other settings the car falls on its face when i accel from a stop.

I fucked with it for the past week and Im pretty much at a point where I ask myself, do I want it to idle, or do I want it to drive good?

[nutz]

tps should be 3-5% to 90-98% never 0 or 100%, and you MUST adjust the tps while the car is running or your values will change (car off and on are different dont know exactly why maybe the alt. volts)


if your car runs great every where but idle i would say dont mess with the tune, try the idle feedback rate ond o2 fb gain @ idle sometimes its just the computer is making very drastic changes and over shooting the rpm and A/F lowering the gain and raising the fb rate helps this (it does for me)

also make sure there isnt drastic changes in between the cells you car idles in (PW or timing) remember the comp interpolates between cells and if its not set up right a fluctuation of a couple hundred RPM's can make huge changes in fuel and timing makeing it unstable, the closest cells at idle should be close in rpm and vac to the idle cells

[05plsrt4]

Its strange...if you search AEM forums they tell you to make sure that the TPS is adjusted so that you read 0% TPS when the throttle is slightly open.

I've been basing everything off that and thats why i was never able to get it to idle right.

Now that i changed that it idles great, but the tune is off.

[never2muchboost]

never set an srt4 tps to read 0% it will shit in your picnic basket

[duster360]

Quote: Originally Posted by never2muchboost

it will shit in your picnic basket

Sounds serious,,,lol