P0300 Code pulled, looking for advice!
Thread Starter
Racer
Joined: Sep 2008
Posts: 293
Likes: 2
From: Newark NJ
P0300 Code pulled, looking for advice!
I was drive a few days ago and it felt like I had a cam in the car....boom Service Engine light flickers and I pull a P0300 code. Doing some research on these forums I felt like I needed to replace the spark plugs...while I put some NGK's and some new GM Hotwire Wires I'm still getting the same issue. I then took it to my guy for injector cleaning. Afterwhich It still does the same thing. I'm guessing my MSD Ignition coils are going...is this the next think I should fix. Should I just go back to stock GM's? If so does anyone have any new or slightly used set of 8 I'm located in North Newark NJ.
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From: Fort Wayne IN
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Is the P300 the only code present? If it is, then you've got to look at what would cause a mulit-cylinder random misfire. Things that would come to mind would be weak fuel pressure, MAF, camshaft position sensor or crank position sensor, and oxygen sensors getting lazy. Best bet is going to be to get it on a laptop for some data logging if you've got anyone local that could help.
Thread Starter
Racer
Joined: Sep 2008
Posts: 293
Likes: 2
From: Newark NJ
Is the P300 the only code present? If it is, then you've got to look at what would cause a mulit-cylinder random misfire. Things that would come to mind would be weak fuel pressure, MAF, camshaft position sensor or crank position sensor, and oxygen sensors getting lazy. Best bet is going to be to get it on a laptop for some data logging if you've got anyone local that could help.
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St. Jude Donor '03
P0300 doesn't have to mean "multiple" misfires.
In these cars it is a catch-all code for ANY misfire detected....the DIC diagnostics do not have the capability to display a "P0304" (for example - would indicate cyl 4 is the one misfiring)....but better scan tools do have the capability to display individual cylinder misfires, which can help a great deal in troubleshooting.
If the misfire is not there consistently, then it definitely seems more ignition related (as opposed to other common causes like fuel delivery or broken valve spring), and in that case I would get it to someone with a real scan tool, and hopefully identify which cylinder may be causing it.
In these cars it is a catch-all code for ANY misfire detected....the DIC diagnostics do not have the capability to display a "P0304" (for example - would indicate cyl 4 is the one misfiring)....but better scan tools do have the capability to display individual cylinder misfires, which can help a great deal in troubleshooting.
If the misfire is not there consistently, then it definitely seems more ignition related (as opposed to other common causes like fuel delivery or broken valve spring), and in that case I would get it to someone with a real scan tool, and hopefully identify which cylinder may be causing it.
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Joined: Mar 2004
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From: Fort Wayne IN
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Really??? The DIC can't display P0301 through P0308?? WTF man? In that case, my suggestion would be go to Advance Auto Parts, Auto Zone, whomever you've got local and have them put their scanner on it and see if it's truly a P0300 or a single cylinder misfire being shown.
Good call Y2K, taught me something today.
Good call Y2K, taught me something today.
Race Director
Joined: Oct 2002
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From: Gone
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Thread Starter
Racer
Joined: Sep 2008
Posts: 293
Likes: 2
From: Newark NJ
I got pissed off a few hours ago and started reading about MSD's on these vette's. I've replacated the issue and it seems to be a coil pack. I've called CarTek and had them order me Stock GM coil packs...I'm going to grab them and slap them in I'll update you at a later date.
Thread Starter
Racer
Joined: Sep 2008
Posts: 293
Likes: 2
From: Newark NJ
UPDATE: I sold my MSD's labeled broken on the bay for 380 bucks. CarTek charged me 480 for all coil packs...I'd say 100 bucks isnt bad for NEW Stock Coils....Woohoo can't wait, with all the new wires I put in and the injector cleaning this puppy should idle perfectly. After I'm done and over with I'm gonna get a nice *** tune!
Waiting for the up-date day...
