strong smell of gas from exhaust hve afr readings
03-03-2015, 06:16 PM
#1
strong smell of gas from exhaust hve afr readings guys my car has a strong smell of gas coming from the exhaust at idle. Air fuel ratio is about 15.5 to 16.0 at idle 800 rpm which I feel like is pretty lean but the smell is killing me. Any ideas
03-04-2015, 04:48 AM
#2
If you have true duals, put the wide band sensor in the other pipe. If you can't mount it in other pipe, check temp of each primary tube of exhaust header to see if one is much cooler than the others. The running rich (gas smell) is probably on the opposite side of the bank where wide band is reading. Might also be that your air pump has failed, if the problem is happening @ start up & if you are still using one. Is your gas cap on tight? Any engine codes?
03-04-2015, 06:19 PM
#4
If you have true duals, put the wide band sensor in the other pipe. If you can't mount it in other pipe, check temp of each primary tube of exhaust header to see if one is much cooler than the others. The running rich (gas smell) is probably on the opposite side of the bank where wide band is reading. Might also be that your air pump has failed, if the problem is happening @ start up & if you are still using one. Is your gas cap on tight? Any engine codes?
don't have true duals, I have tsp longtubes ypipe setup, wideband is in the drivers side ypipe right after the header. Gas cap is on tight and no engine codes a frost just tuned it.
03-05-2015, 10:15 AM
#5
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Gas smell is elevated HC and you can get that at either end
of the AFR range. Lean misfires would fit the symptoms and
can also bend wideband (and narrowband) readings. Poor
atomization (like in worked heads with no swirl ramps anymore)
can make low RPM combuation incomplete throwing air to the
exhaust stream and spoofing the meter, even if chemically
rich.
But you also cannot discount out of hand things like an
injector imbalance (esp. near the min pulse end where a
little bit sticky can really change actuation). Look to the
misfire counts for any that stand out.
of the AFR range. Lean misfires would fit the symptoms and
can also bend wideband (and narrowband) readings. Poor
atomization (like in worked heads with no swirl ramps anymore)
can make low RPM combuation incomplete throwing air to the
exhaust stream and spoofing the meter, even if chemically
rich.
But you also cannot discount out of hand things like an
injector imbalance (esp. near the min pulse end where a
little bit sticky can really change actuation). Look to the
misfire counts for any that stand out.
03-05-2015, 08:06 PM
#7
Gas smell is elevated HC and you can get that at either end
of the AFR range. Lean misfires would fit the symptoms and
can also bend wideband (and narrowband) readings. Poor
atomization (like in worked heads with no swirl ramps anymore)
can make low RPM combuation incomplete throwing air to the
exhaust stream and spoofing the meter, even if chemically
rich.
But you also cannot discount out of hand things like an
injector imbalance (esp. near the min pulse end where a
little bit sticky can really change actuation). Look to the
misfire counts for any that stand out.
of the AFR range. Lean misfires would fit the symptoms and
can also bend wideband (and narrowband) readings. Poor
atomization (like in worked heads with no swirl ramps anymore)
can make low RPM combuation incomplete throwing air to the
exhaust stream and spoofing the meter, even if chemically
rich.
But you also cannot discount out of hand things like an
injector imbalance (esp. near the min pulse end where a
little bit sticky can really change actuation). Look to the
misfire counts for any that stand out.
how do you fix the injector imbalance? saying if I had one. I did have a few misfire miscounts at idle, fixed the one bad plug wire car ran better but at idle there is misfire miscounts, as soon as I rev just a little they all clear up
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03-08-2015, 11:20 PM
#8
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A few misfires jumping around is normal. What to worry
about is a cylinder that sticks out and doesn't come and
go.
An injector clean & flow test service would tell you, and
I have made my own fuel injector tester out of junkyard
and junk box parts before (back when EFI was voodoo
and nobody could help you). Fixed the 5.0 wifemobile by
buying a set of junkyard injectors and testing all 16,
putting back in the 8 tightest grouped.
You can inspect for drool or bad spray pattern by eye
if you can get pressure and signal to the piece, you
need a repeatable pulse train to do fuel-volume (or
mass) matching tests.
about is a cylinder that sticks out and doesn't come and
go.
An injector clean & flow test service would tell you, and
I have made my own fuel injector tester out of junkyard
and junk box parts before (back when EFI was voodoo
and nobody could help you). Fixed the 5.0 wifemobile by
buying a set of junkyard injectors and testing all 16,
putting back in the 8 tightest grouped.
You can inspect for drool or bad spray pattern by eye
if you can get pressure and signal to the piece, you
need a repeatable pulse train to do fuel-volume (or
mass) matching tests.
03-09-2015, 07:13 PM
#9
A few misfires jumping around is normal. What to worry
about is a cylinder that sticks out and doesn't come and
go.
An injector clean & flow test service would tell you, and
I have made my own fuel injector tester out of junkyard
and junk box parts before (back when EFI was voodoo
and nobody could help you). Fixed the 5.0 wifemobile by
buying a set of junkyard injectors and testing all 16,
putting back in the 8 tightest grouped.
You can inspect for drool or bad spray pattern by eye
if you can get pressure and signal to the piece, you
need a repeatable pulse train to do fuel-volume (or
mass) matching tests.
about is a cylinder that sticks out and doesn't come and
go.
An injector clean & flow test service would tell you, and
I have made my own fuel injector tester out of junkyard
and junk box parts before (back when EFI was voodoo
and nobody could help you). Fixed the 5.0 wifemobile by
buying a set of junkyard injectors and testing all 16,
putting back in the 8 tightest grouped.
You can inspect for drool or bad spray pattern by eye
if you can get pressure and signal to the piece, you
need a repeatable pulse train to do fuel-volume (or
mass) matching tests.