Running very rich at idle??
Running very rich at idle?? The car is running so rich at idle that it will burn your eyes. I am trying to figure out where to correct this in HPTuners. It is really bad when it first cranks and idles. I am assuming that this is when it is in open loop since it hasn't had the time to warm up yet, right? Where else should I be looking? Main VE?
If you are only going on what your eyes are telling you, you might think it is running richer than it actually is. You need a wideband to verify what the AFR is. My car without cats smells rich, but isn't.
Yeah, it is probably running rich then. Get the wideband installed and let us know what it is reading. On cold starts (and warm starts until the O2 sensors are heated and the PCM falls into closed loop operation), the Open Loop Fuel/Air table controls the fueling. It doesn't work intuitively though, so I wouldn't recommend changing it *****-nilly. In closed loop, however, the O2 sensors control the fueling. So if it still runs rich in close loop, you have a problem with the O2 sensor settings.
Originally Posted by MeentSS02
If you are only going on what your eyes are telling you, you might think it is running richer than it actually is. You need a wideband to verify what the AFR is. My car without cats smells rich, but isn't.
(just could not find the right smile) 
What he said is exactly what you need to do. OLSD tuning will help as well with a BIG cam. Narrow band tuning (O2's) suck for looking a FAT idle conditions.
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Originally Posted by 2xLS1
Is this problem on the car with the T-rex?
Yes it is. I have the FAST dual sensor wideband that I am going to try to install this week. The car has been tuned WOT so I am not as worried about that. It just seems like it needs a little changing on the low end.
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The depressed MAP from the cam is indexing you to a
very fat place in the EQ vs ECT vs MAP table (OLFA).
This is your cold running (over)enrichment. You need
to skinny down the mid-MAP (where you idle, and
below) cold enrichment to something more sensible.
This should also take out a lot of surging at idle.
The air shoot-through from that cam into the exhaust
is going to hurt your fuel trimming accuracy. This is
where some of the closed loop idle trim error will
remain, even if you fix up the VE table (which it will
need plenty of, on up to 2000RPM).
Between those two you are overfueled both by
command (EQ) and error (VE), further depressing
MAP and driving you even deeper into it.
Idle at >800RPM with that cam or you'll have even
more of a fight.
On the other computer I have a pretty good TRex VE
table; I know I've posted it here before but I will
try and dig it up for post.
very fat place in the EQ vs ECT vs MAP table (OLFA).
This is your cold running (over)enrichment. You need
to skinny down the mid-MAP (where you idle, and
below) cold enrichment to something more sensible.
This should also take out a lot of surging at idle.
The air shoot-through from that cam into the exhaust
is going to hurt your fuel trimming accuracy. This is
where some of the closed loop idle trim error will
remain, even if you fix up the VE table (which it will
need plenty of, on up to 2000RPM).
Between those two you are overfueled both by
command (EQ) and error (VE), further depressing
MAP and driving you even deeper into it.
Idle at >800RPM with that cam or you'll have even
more of a fight.
On the other computer I have a pretty good TRex VE
table; I know I've posted it here before but I will
try and dig it up for post.
i have the same problem with my setup, i've had it tuned twice and that hasn't done a bit of difference. I now have hptuners myself but am just learning, is there any way that i could post up my log and one of you take a look at it and give me suggestions on what to correct?
The car will not idle upon initial startup, after like 30 seconds of keeping it alive it is fine. I have an MTI x1 cam. Idle is set at 800 i'm pretty sure. It fouls plugs but my wideband is telling me that the car is running lean at idle. idk its a huge disaster that i've been trying to solve for the past year and a half. Any help would be appreciated , thanks a bunch!
Oh btw the heads are stock, everything else in the sig is correct.
The car will not idle upon initial startup, after like 30 seconds of keeping it alive it is fine. I have an MTI x1 cam. Idle is set at 800 i'm pretty sure. It fouls plugs but my wideband is telling me that the car is running lean at idle. idk its a huge disaster that i've been trying to solve for the past year and a half. Any help would be appreciated , thanks a bunch!
Oh btw the heads are stock, everything else in the sig is correct.
Last edited by MadMike; Dec 18, 2006 at 08:49 PM.
I dug it up but this site will not let me attach it, the
old HPTuners .bin format is not supported and zip'd
is still too big for that format limit. So I have to go
find a file host. Or you can PM me an email address
that can take a 800+KB attachment. But I want to
get it hosted for general, anyway.
old HPTuners .bin format is not supported and zip'd
is still too big for that format limit. So I have to go
find a file host. Or you can PM me an email address
that can take a 800+KB attachment. But I want to
get it hosted for general, anyway.
