Looking for LS1 PCM internal schematic for P0200 issues and misfires on 4 & 7
06-17-2014, 10:20 PM
#1
Looking for LS1 PCM internal schematic for P0200 issues and misfires on 4 & 7 Hello all,
I have an issue with my 2001 Camaro SS, I'm getting a P0200 code.
After the long winter I finally got my car out of storage and now I have the P0200 code. Car was in a heated garage all winter. When I drive the car and put a load on it, say 50% throttle or even 100% throttle, it start to break up, backfire, spit and spudder. I let off the gas and it runs fine. It starts up fine, idles fine and even revs fine in the driveway. The backfire is not consistent, sometimes it will do it at 3,000 rpms and sometimes at 5,000 rpms at WOT or 50% or more load.
I am also getting misfires on Cylinders 4 and 7 when I get the RPMs up around 2,000 or more.
I swapped coils and injectors with others that were not getting misfires, plugs, wires, etc and I still have misfires on cylinders 4 and 7. I ohmed out the injectors and they are all around 12.8 ohms. I get 12.5 volts at each injector. So no matter what I swap, the misfire are always on 4 & 7.
I just wonder inside the PCM if injectors 4 and 7 are linked electronically inside the PCM. I do electrical and electronics for a living so I know my way around a circuit boards and electronic schematics. I'm even thinking of getting out my oscilloscope to check the square wave of injectors 4 and 7 to see if the wave goes to hell when I'm getting the misfires.
With work, a family and the daily routine, I can really only troubleshoot it maybe 2-3 hours a day. I'm at a loss at this point, any help is appreciated.
I have an issue with my 2001 Camaro SS, I'm getting a P0200 code.
After the long winter I finally got my car out of storage and now I have the P0200 code. Car was in a heated garage all winter. When I drive the car and put a load on it, say 50% throttle or even 100% throttle, it start to break up, backfire, spit and spudder. I let off the gas and it runs fine. It starts up fine, idles fine and even revs fine in the driveway. The backfire is not consistent, sometimes it will do it at 3,000 rpms and sometimes at 5,000 rpms at WOT or 50% or more load.
I am also getting misfires on Cylinders 4 and 7 when I get the RPMs up around 2,000 or more.
I swapped coils and injectors with others that were not getting misfires, plugs, wires, etc and I still have misfires on cylinders 4 and 7. I ohmed out the injectors and they are all around 12.8 ohms. I get 12.5 volts at each injector. So no matter what I swap, the misfire are always on 4 & 7.
I just wonder inside the PCM if injectors 4 and 7 are linked electronically inside the PCM. I do electrical and electronics for a living so I know my way around a circuit boards and electronic schematics. I'm even thinking of getting out my oscilloscope to check the square wave of injectors 4 and 7 to see if the wave goes to hell when I'm getting the misfires.
With work, a family and the daily routine, I can really only troubleshoot it maybe 2-3 hours a day. I'm at a loss at this point, any help is appreciated.
06-18-2014, 04:52 AM
#2
On The Tree
Join Date: Aug 2011
Location: Indiana
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If it was fine when you put it away, I would look at fueling. Perhaps some flaky injectors or bad gas. Did you put Sta-bil in the tank when you stored it? Maybe the injectors varnished up.
You can move the injectors to see if your issues move by pulling the fuel rail.
You can move the injectors to see if your issues move by pulling the fuel rail.
06-18-2014, 07:40 AM
#3
I've had the car since new and always store it the same way, fill the tank, put Sta-bil in the tank. Yes I did move the injectors and the misfires did not follow the suspected injectors. If it was bad gas, other cylinders would have misfires but its always #4 and 7 no matter what I swap around.
I'm going to try a different set of coil packs and brackets that I know are good and then if that doesn't help, I have another PCM I can flash my tune to and see if that helps.
I'm going to try a different set of coil packs and brackets that I know are good and then if that doesn't help, I have another PCM I can flash my tune to and see if that helps.
07-22-2014, 12:33 AM
#5
I finally figured out what my issue was. It ended up being a bad coil pack. I put on another set of coil packs with brackets and harness and the problem went away. Through process of elimination I found the bad one. Never would have thought that since I was getting a injector control circuit code. Hope this helps others out in the future.
07-22-2014, 05:09 PM
#6
I finally figured out what my issue was. It ended up being a bad coil pack. I put on another set of coil packs with brackets and harness and the problem went away. Through process of elimination I found the bad one. Never would have thought that since I was getting a injector control circuit code. Hope this helps others out in the future.
I see too many cases where a code leads someone down the wrong path for too long. I think thats why most dealerships are constantly chasing their tail with codes, as they can't imagine it could be something else entirely
07-23-2014, 07:18 PM
#7
I finally figured out what my issue was. It ended up being a bad coil pack. I put on another set of coil packs with brackets and harness and the problem went away. Through process of elimination I found the bad one. Never would have thought that since I was getting a injector control circuit code. Hope this helps others out in the future.
Glad you found your problem.
