Stop drilling those TBs, fix stalling without computer tuning...
TECH Junkie
Joined: Dec 2001
Posts: 3,242
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From: Lakeland, FL
I just got done doing this and have my IACs at 30 with no ac and 90 with AC. This is the best idling cammed car I've had yet 
. How much difference do you guys think it would make if I went for IAC's of 40?
. How much difference do you guys think it would make if I went for IAC's of 40? 
Thread Starter
TECH Addict
Joined: Feb 2004
Posts: 2,826
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Originally Posted by Mike K.
I just got done doing this and have my IACs at 30 with no ac and 90 with AC. This is the best idling cammed car I've had yet . How much difference do you guys think it would make if I went for IAC's of 40?
. How much difference do you guys think it would make if I went for IAC's of 40? TECH Junkie
Joined: Dec 2001
Posts: 3,242
Likes: 0
From: Lakeland, FL
It idles really good now with an occasional dip in rpms when stopping, when this happens though my IAC counts go higher than 30 for some reason. I'll leave it like it is for now and see what happens. Thanks for posting this method up.
I just done this on my 02 silverado with an aftermarket cam. The main problem I was having was with the A/C on stopping at redlights, sometimes the truck idle would dip and hunt for an idle (even with the idle tables raised with edit). This mod completely eliminated all of the dips and the truck idles perfectly now. THANKS.
TECH Enthusiast
Joined: Apr 2004
Posts: 749
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From: Chandler, Arizona
I put in a TSP224 cam in this weekend and with my A/C on it would die at a stoplight. Really got tired of doing the heel and toe to keep it running and stop at the same time. I did this mod and now it idles great. Tried 3% right off the bat and the idle was perfect. Only problem is what the above post stated, I get a cruise control affect or overrun until I hit the brake. It's like the cruise is on at around 2000 rpm. Did I go too far? I'm ready to try 2% and see if it will act better.
Thanks,
Glenn
Thanks,
Glenn
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Is there anyway you could do this without having autotap? Like say a magic # of turns of the screw, and just guess it. Trial and Error persae? Would it mess anything up? How many turns is the average ?
On The Tree
Joined: May 2004
Posts: 133
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From: Dallas
if you make ANY adjustments to the set screw, you MUST go through the idle relearn procedure and reset the TPS. Otherwise the computer will think your throttle is open a tick more and will slowly accelerate. Gotta do it every time. That should remedy your "cruise" effect. If not, you might want to adjust your idle tables.
Thread Starter
TECH Addict
Joined: Feb 2004
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Originally Posted by TIMMEH
if you make ANY adjustments to the set screw, you MUST go through the idle relearn procedure and reset the TPS. Otherwise the computer will think your throttle is open a tick more and will slowly accelerate. Gotta do it every time. That should remedy your "cruise" effect. If not, you might want to adjust your idle tables.
You TPS is used in calculating a lot of things like part throttle air in gear, etc, and whether or not you are in idle. If you do not reset the TPS it will also cause a lot of problems. Thats why you have to reset it.
I just did this...and yes, it idles much better, however, it seems this affects my TC lockup and gas mileage.
It seems to take a while longer for the TC to lockup...maybe it's my imagination.
Also, the gas mileage might be my heavy foot, I dont know
It seems to take a while longer for the TC to lockup...maybe it's my imagination.
Also, the gas mileage might be my heavy foot, I dont know
TECH Enthusiast
Joined: Apr 2004
Posts: 749
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From: Chandler, Arizona
I reset my TPS by pulling out the plug to it, turned the key on, turned the key back off and replugged in the TPS. I then went through the 5 minutes of idling with the A/C off for it to relearn the idle after disconnecting the battery for a few minutes.
After all of this, I still have a terrible "cruise control" effect. And all of this was with the idle screwed back in to almost where it was stock, if I go any further the car quits at a stop light with the A/C on. So I guess I'm going to have to fix this with tuning? I just hope I can fix it, I hate the feeling of letting off the gas and having the car keep going. Don't like having to stand on the brakes all the time. What has to be adjusted with the tune to fix this?
Thanks,
Glenn
After all of this, I still have a terrible "cruise control" effect. And all of this was with the idle screwed back in to almost where it was stock, if I go any further the car quits at a stop light with the A/C on. So I guess I'm going to have to fix this with tuning? I just hope I can fix it, I hate the feeling of letting off the gas and having the car keep going. Don't like having to stand on the brakes all the time. What has to be adjusted with the tune to fix this?
Thanks,
Glenn
I tried this last night and it did work to some degree but it still surges at warm, prolonged idle. The car is an A4 with a 111 LSA that has been tuned recently. It does idle better now than before (after tune). The cruise control effect (on decel) has also been reduced a little. I wonder if increasing the TPS to 4% will help? I set it at 3.1% the first time.
There must be some advantage to reading zero tps rather than some low positive value. At what TPS does the switch from the base spark tables to the High octane timing table occur?
BLKTA, I set mine to 3% and it idles great, right at about 675....but I dont have a 111 lsa in an A4
ps, how do you like that cam?
edit: i should mention i had already drilled my tb, but that had just about no effect on idling..
ps, how do you like that cam?
edit: i should mention i had already drilled my tb, but that had just about no effect on idling..
99ssleeper - The cam has a real mean idle to it (should be out at Uni this weekend), but unfortunately the numbers don't back the sound up. I will redyno today,then probably go with a different cam like the TSP 231/231. Mine idles around 850 rpms and I didn't drill the TB blade.
On The Tree
Joined: May 2004
Posts: 133
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From: Dallas
I know all cars are different, but in my case I reset the TPS after every tune...especially if I adjust the set screw...just in case. Another_User is correct in saying that you don't have to do a complete idle relearn but it doesn't hurt. The process I go through is when the car's off...I'll unplug the TPS. Switch it to on for 10 seconds, then turn it off and re-plug in the TPS. Fire it up and let it run in neutral for about a minute...then in gear for a minute. Flip on the AC for a minute in gear, then in park. That's it.
Glenn, to answer your question about what needs to be adjusted, it's a matter of what your car is doing and what mods you have done. Changing the engine idle speed, Idle Air, and IAC park position...and some adjustments to the timing and VE tables are usually the key tables for fixing idle issues.
Glenn, to answer your question about what needs to be adjusted, it's a matter of what your car is doing and what mods you have done. Changing the engine idle speed, Idle Air, and IAC park position...and some adjustments to the timing and VE tables are usually the key tables for fixing idle issues.