video of "part throttle lean" condition!! tuners please advise!!
#1
video of "part throttle lean" condition!! tuners please advise!!
So here is the problem im having. the car goes super lean at part throttle only when the engine is at operating temperature. WOT the car runs great, and it idles great. its only at part throttle/ cruising speeds. The car has an SD tune programmed to run open loop. its an ebay kit, but has been modified to take a 50mm turbosmart wastegate and 76mm .81 a/r turbo. im running 7-8 psi.
fuel is walbro pump, stock lines, edelbrock fuel rails, 50# injectors.
we tried to fix this on the dyno but had no luck tuning it out. I have no knowledge about tuning, so if im leaving out any important info let me know.
the gauge only reads to 16 but on the dyno it is actually leaning out to 20:1 which is why the motor is running so crappily as you can hear in the vid
http://www.youtube.com/watch?v=GGvHxObI5lg
any ideas,????? my brain is fried after troubleshooting for a week!
.
fuel is walbro pump, stock lines, edelbrock fuel rails, 50# injectors.
we tried to fix this on the dyno but had no luck tuning it out. I have no knowledge about tuning, so if im leaving out any important info let me know.
the gauge only reads to 16 but on the dyno it is actually leaning out to 20:1 which is why the motor is running so crappily as you can hear in the vid
http://www.youtube.com/watch?v=GGvHxObI5lg
any ideas,????? my brain is fried after troubleshooting for a week!
.
#2
forgot to mention:
using HP tuners.. has a 2 bar MAP from a colbalt
ive tried disconnecting the WG, i get the same AFR readings even with no boost.
disconnected the tube going to the TB, same AFR readings w/ no boost
ive swapped coils, bought new wires, and new TR6 plugs gapped at .035" and the problem is still there.
using HP tuners.. has a 2 bar MAP from a colbalt
ive tried disconnecting the WG, i get the same AFR readings even with no boost.
disconnected the tube going to the TB, same AFR readings w/ no boost
ive swapped coils, bought new wires, and new TR6 plugs gapped at .035" and the problem is still there.
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#8
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That sounds terrible.
Check the VE table in the low RPM (where it is happening), medium to high load range 40 - 80 kpa.
Those VE values may have to be increased by 30 - 50% or more.
At WOT your PE may be saving you - covering up a lean VE table.
It might help you to lower your PE to something like 10% across the board, then get the VE table in better shape. That way there will be less transition to PE, and you can add a little low RPM PE to simulate more pump-shot.
This is very common after adding heads, cam, exhaust, and/or larger intake manifold. The actual VE at part throttle is much higher than that predicted for a stock engine. Add fuel in the right places and it's done.
Check the VE table in the low RPM (where it is happening), medium to high load range 40 - 80 kpa.
Those VE values may have to be increased by 30 - 50% or more.
At WOT your PE may be saving you - covering up a lean VE table.
It might help you to lower your PE to something like 10% across the board, then get the VE table in better shape. That way there will be less transition to PE, and you can add a little low RPM PE to simulate more pump-shot.
This is very common after adding heads, cam, exhaust, and/or larger intake manifold. The actual VE at part throttle is much higher than that predicted for a stock engine. Add fuel in the right places and it's done.
#9
I find it funny this "tuner" let you leave when it was running like that. Got any names or whatever of this tuner place?
#12
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Does it sound like its running on 7? Injectors aren't the issue there easy to sort. turn the STFTs on and do a log. It will sit on 14.7 until PE drive it around for 20 minutes or so and fill the log up in the tune.
Make sure in the STFT map you change the source from "sensor" to "pid" I have had dicky readings with HPT otherwise if you are using efilive its not an issue.
The motor should sound smoother whilst driving and the log will highlight leanspots simply copy then past and multiply to your VE table, Go for another drive in OL and see what happens, it should be close if not its not a tune issue. Possibly ignition somewhere.
Make sure in the STFT map you change the source from "sensor" to "pid" I have had dicky readings with HPT otherwise if you are using efilive its not an issue.
The motor should sound smoother whilst driving and the log will highlight leanspots simply copy then past and multiply to your VE table, Go for another drive in OL and see what happens, it should be close if not its not a tune issue. Possibly ignition somewhere.