Scantool has strange results
#1
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Scantool has strange results
I picked up a used PDA and Autotap from INTENSE and fired it up today with a buddy in Forest Park, IL. Well our findings were confusing....
At first the IPW bank 1 counts were REALLY low once the engine was at operating temp, we're talking down to the 20'*!
So I did a small reverse procedure on the TPS mod and brought down the idle voltage. Then the idle screw wouldn't change the voltage value after it was losened so much, so I move the TPS slightly to bring down WOT voltage a tiny bit. I got idle down from .71 to .63 and the IPW counts seemed to say at 47 at idle, so that'* an improvement.
Still one big problem. Why are my long term fuel trims still maxing out to 16.4 at idle? I can be cruising down the road and they will be between 8 to 10.6, but the second I let off the gas they peg 16.4.
We even slapped on a mini-AFC 2.0 and brought up the idle Hz values up and the trims were still high. However, the short term fuel trims seem "ok"...meaning they bounce around somewhat and when I continuously changed throttle on the road they bounced around from negative to positive and so forth.
We sprayed TB cleaner all over every vacuum line fitting I could think off and the idle didn't change at all, so in turn we couldn't find any leaks. o2 readings seem normal as they bounce all over, but could it still be going bad?
So who here knows what their IPW counts are and trim levels? Please post your values and give me some guidance of where to start testing/looking for causes of a high L-trim.
At first the IPW bank 1 counts were REALLY low once the engine was at operating temp, we're talking down to the 20'*!
So I did a small reverse procedure on the TPS mod and brought down the idle voltage. Then the idle screw wouldn't change the voltage value after it was losened so much, so I move the TPS slightly to bring down WOT voltage a tiny bit. I got idle down from .71 to .63 and the IPW counts seemed to say at 47 at idle, so that'* an improvement.
Still one big problem. Why are my long term fuel trims still maxing out to 16.4 at idle? I can be cruising down the road and they will be between 8 to 10.6, but the second I let off the gas they peg 16.4.
We even slapped on a mini-AFC 2.0 and brought up the idle Hz values up and the trims were still high. However, the short term fuel trims seem "ok"...meaning they bounce around somewhat and when I continuously changed throttle on the road they bounced around from negative to positive and so forth.
We sprayed TB cleaner all over every vacuum line fitting I could think off and the idle didn't change at all, so in turn we couldn't find any leaks. o2 readings seem normal as they bounce all over, but could it still be going bad?
So who here knows what their IPW counts are and trim levels? Please post your values and give me some guidance of where to start testing/looking for causes of a high L-trim.
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Never touched an IAC before, I can just unscrew the 2 screws and clean it with TB cleaner?
Anyway I did some quick/rough Autotap runs by looking at the PDA while flooring it. This is what I found out:
o2'* seem low at WOT: 880-910
KR was all over from 1.9 to 4.1, but not bad for how small of a pulley I have on compared to my mods.
Ignition Timing Advance: 50-90mph I saw it go as low as 7.0
Little thing I noticed, after going WOT and letting go of the gas at the top of 2nd (100mph) all numbers on the PDA froze at 0 for some time or until I tapped the gas lightly.
Anyway I did some quick/rough Autotap runs by looking at the PDA while flooring it. This is what I found out:
o2'* seem low at WOT: 880-910
KR was all over from 1.9 to 4.1, but not bad for how small of a pulley I have on compared to my mods.
Ignition Timing Advance: 50-90mph I saw it go as low as 7.0
Little thing I noticed, after going WOT and letting go of the gas at the top of 2nd (100mph) all numbers on the PDA froze at 0 for some time or until I tapped the gas lightly.
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I changed my oil today and took the IAC out...well it was BLACK! I used some TB cleaner on it and cleaned some off the gunk off. Good news is my IAC counts went up from 37 to 41ish at idle. But I'm throwing the P171 code like a ****. Bad o2?
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Originally Posted by Allmachtige
I changed my oil today and took the IAC out...well it was BLACK! I used some TB cleaner on it and cleaned some off the gunk off. Good news is my IAC counts went up from 37 to 41ish at idle. But I'm throwing the P171 code like a ****. Bad o2?
I would still say to clean out your entire TB, its cheap, at the least you get better throttle response, and relativly easy.
Any way to check if the O2 is working right with the scantool?
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TB is cleaned twice recently...thats not it.
P171 is lean condition on bank 1.
I think the o2 is a little quirky because I should be getting higher o2 numbers at WOT.
P171 is lean condition on bank 1.
I think the o2 is a little quirky because I should be getting higher o2 numbers at WOT.