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Loose plugs and error codes

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Old May 23, 2023 | 10:33 AM
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Default Loose plugs and error codes

Hello, I have 81/4 spd stock except the q-jet was replaced by a Holley and air pump removed (previous owner). I have error codes 21 (TPS-throttle position sensor) and 23 (mixture control solenoid). Do you know what those loose plugs were used for (I guess it was carb info to ecm..). Do my errors codes related to the missing air pump and the missing q-jet? Thanks!

Last edited by by667; May 23, 2023 at 01:49 PM. Reason: correction on error code 23
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Old May 23, 2023 | 10:45 AM
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St. Jude Donor '22
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uh, yes
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Old May 23, 2023 | 10:48 AM
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You also should no longer have the stock distributor. Does your distributor have a vacuum advance diaphragm?
How are you activating the lockup torque converter?
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Old May 23, 2023 | 11:15 AM
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St. Jude Donor '22
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remove ecu fuse
your orig distributor will only give you @6 to maybe 8 deg of advance total.
it needs computer to give more so your performance is way down.
a vacuum distributor will give you , ****, like 40--+
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Old May 23, 2023 | 11:30 AM
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yeah, i'm a bit confused about that... I have the original dist (no vacuum, no weights). My timing adv numbers are: 12 deg@900 rpm, 24 deg@2000 rpm and 30 deg@3000 rpm. So I guess the ECU is able to do some timing advance without the q-jet info...???
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Old May 23, 2023 | 11:44 AM
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Originally Posted by by667
yeah, i'm a bit confused about that... I have the original dist (no vacuum, no weights). My timing adv numbers are: 12 deg@900 rpm, 24 deg@2000 rpm and 30 deg@3000 rpm. So I guess the ECU is able to do some timing advance without the q-jet info...???
Apparently yes, but at cruising speeds, 3k rpm, 46 to 48 would be typical with vacuum advance, 36 mechanical the rest vacuum.
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Old May 23, 2023 | 12:02 PM
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Originally Posted by by667
yeah, i'm a bit confused about that... I have the original dist (no vacuum, no weights). My timing adv numbers are: 12 deg@900 rpm, 24 deg@2000 rpm and 30 deg@3000 rpm. So I guess the ECU is able to do some timing advance without the q-jet info...???
wow, I am surprised.
Better than I thought.
thats driveable.
computer doing work.
thanks for the info
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Old May 23, 2023 | 12:17 PM
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St. Jude Donor '22
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the throttle position code needs a carb with the rheostat
the map code is curious, it is drv side fire wall with a small vac hose and
should affect timing.
maybe someone figured out that unplugging it makes comp add timing?
very interesting.
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