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I got a P0354 on the CEL and I swapped coil pack four with coil pack 2, high voltage wire 4 with 6, and plug 4 with 8. code came up again 40miles later. Engine runs fine. Any common problems?
History: This code comes up usually after 10 miles of driving. I just got done putting in a new clutch and master cylinder. I did knock loose the low beam light wire under the dash and had to push it back into the connector firmly to resolve this. Also, all ground wires under hood were reaffixed to chassis a couple thousand miles ago via the GM approved method: cut off the connectors and attach them to from via bus bars.
Any common problem that causes this code for others?
The 0354 is a coil pack “control” DTC so did you check the control wire on the coil pack ??…the control wire on #4 is dark green I believe so with the coil pack connector unplugged what voltage do you see on it with the engine running ??…it is a 0-5 volt square wave with a scope but with a DVOM you will see maybe 1 volt…if your DVOM has a frequency setting see what the frequency is…should be around 8-10Hz.
I have not checked with the voltmeter yet but so far I have moved around all the coil packs on both sides of the engine, replaced all the wires and spark plugs. This problem started after I replaced the clutch. What do you think I did wrong? Possibly disconnected a ground wire somewhere that causes this bizarre code, which makes no sense for a loose ground wire?
The control wire voltage on coil pack for is the same as the control wire voltage on coil pack. 2. Don't remember what it was but this code doesn't seem to come up and idle. It only comes up when driving the car. I used to fiber optic camera to trace the wire where it goes behind the engine and down to the PCM and it doesn't seem to be rubbing anywhere. I also have 14 volts on the red wire, a perfect ground on the ground wire and the return wire which is the sensor wire. I think it was brown. I'm really pretty stumped on this one
I got a P0354 on the CEL and I swapped coil pack four with coil pack 2, high voltage wire 4 with 6, and plug 4 with 8. code came up again 40miles later. Engine runs fine. Any common problems?
History: This code comes up usually after 10 miles of driving. I just got done putting in a new clutch and master cylinder. I did knock loose the low beam light wire under the dash and had to push it back into the connector firmly to resolve this. Also, all ground wires under hood were reaffixed to chassis a couple thousand miles ago via the GM approved method: cut off the connectors and attach them to from via bus bars.
Any common problem that causes this code for others?
Although the OP scoped the wire harness, suspect during the clutch replacement the engine rolled back and contacted the fire wall...
Recommend the OP perform [again] a detailed visual inspection of the wire harness looking for any signs of "abrasions", "rub" marks and or "squeeze" marks on the harness.
Cheers,
Goose
It didn't tilt back far at all. Inspected w camera and all looks good w fiberoptic camera. I need some help finding this one. Anyone near Lakeland Florida?
It didn't tilt back far at all. Inspected w camera and all looks good w fiberoptic camera. I need some help finding this one. Anyone near Lakeland Florida?
OK, If you are confident that the harness did not get squeezed during the clutch replacement, recommend you do a detailed visual inspection on the coil harness in the below areas in red.
If no damage is observed in the red area's, recommend removing the coil pack assembly from the rocker cover,
Upon removal of the coil pack assembly from the rocker cover, flip the coil pack over and inspect the wire harness for chaff marks or damage.
Disconnect the number 4 coil, and perform continuity checks from the #4 coil plug to the harness main plug while shaking the wires to see if you have an intermittent "open" wire.
OK, If you are confident that the harness did not get squeezed during the clutch replacement, recommend you do a detailed visual inspection on the coil harness in the below areas in red.
If no damage is observed in the red area's, recommend removing the coil pack assembly from the rocker cover,
Upon removal of the coil pack assembly from the rocker cover, flip the coil pack over and inspect the wire harness for chaff marks or damage.
Disconnect the number 4 coil, and perform continuity checks from the #4 coil plug to the harness main plug while shaking the wires to see if you have an intermittent "open" wire.
I removed the coil pack assembly from the rocker cover. No chafe marks continuity is good. Moving coil packs around doesn't make a difference. Wires are good on visual inspection behind the engine. Following photos shows that the trigger voltage to coil pack for is half that of what goes to the others two, six and eight. What are your thoughts about why the trigger voltage is around 4 volts going to coil pack 4 but it's around 8 volts going to the other packs?
I'm also noticing that the brake pedal is usually applied where the coat is thrown but not always. Not as sure if this is a clue. I have reconnected all the ground wires on the car, cut out all the crappy connectors and soldered them together and bolted them down with a lug. And sometimes I get a stop lamp open circuit signal code. Doesn't make sense. I have no blown out bulbs and I do the wiggle test and nothing is loose back there. The third brake light is LED but that shouldn't be causing a p0354 code
I removed the coil pack assembly from the rocker cover. No chafe marks continuity is good. Moving coil packs around doesn't make a difference. Wires are good on visual inspection behind the engine. Following photos shows that the trigger voltage to coil pack for is half that of what goes to the others two, six and eight. What are your thoughts about why the trigger voltage is around 4 volts going to coil pack 4 but it's around 8 volts going to the other packs?
The trigger voltage is a 0-4 volt square wave you’ll see if you set your time base properly… like 20ms per division….those 8 volt triggers you see are just spikes…don’t know how long you have been using a scope ??…did you check the coil pack current ramps ??
The trigger voltage is a 0-4 volt square wave you’ll see if you set your time base properly… like 20ms per division….those 8 volt triggers you see are just spikes…don’t know how long you have been using a scope ??…did you check the coil pack current ramps ??
I only bought one set of leads and it's a two-channel model 2024a. Should I get another set of leads? I also don't have amp clamps. Can you direct me to which ones to get if I need them?
P0354 obd code
