Got the code read by a guy at Autozone...P0300...
Thread Starter
Burning Brakes
Joined: Apr 1999
Posts: 1,161
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From: Texas
Got the code read by a guy at Autozone...P0300...
He said it was random cylinder misfiring.
The engine was idling and misfiring when he was reading the code. I had him clear the SES light. I drove home and the light didn't come back on but it continued to run rough all the way. Seems to be worse after it warms up.
I went home and sprayed down the spark plug wires with a hand held sprayer according to the Helms manual to try to determine if the prob was plug wires shorting. No change, I pushed in on the coil wire and checked the plug wires visually, those buggers are pretty hard to get to in many areas, couldn't find anything wrong. I'm guessing it's a carbon tracking issue inside the opti.
Guess I'll order an Optispark, & plugs and wires while I'm at it...
Anything else I should do while I'm in there...???
thanks
dr
The engine was idling and misfiring when he was reading the code. I had him clear the SES light. I drove home and the light didn't come back on but it continued to run rough all the way. Seems to be worse after it warms up.
I went home and sprayed down the spark plug wires with a hand held sprayer according to the Helms manual to try to determine if the prob was plug wires shorting. No change, I pushed in on the coil wire and checked the plug wires visually, those buggers are pretty hard to get to in many areas, couldn't find anything wrong. I'm guessing it's a carbon tracking issue inside the opti.
Guess I'll order an Optispark, & plugs and wires while I'm at it...
Anything else I should do while I'm in there...???
thanks
dr
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,009
From: Texas
Re: Got the code read by a guy at Autozone...P0300... (DavidR)
Before you spring for an Opti, replace the plugs and wires. If you still have the problem, then do the Opti.
If the plugs are original, it's not unusual for them to lose the platinum pucks on the ground electrode. When this happens, the gap increases to ~.065 from .050. My last set of AC Delco double platinums had less than 40k miles on them. 6 of the 8 were missing their pucks when I pulled them. I use Denso Iridium IT20s now, but NGK TR55ix are also good.
Lastly, my experience is that you can get about 40k out of a set of stock GM plug wires. If you didn't buy the car new, you can tell if they're the original wires if each wire has the cylinder number printed on it. Only the original, installed in Bowling Green, plug wires have this. OEM wires sold over the counter at the dealer do not. I personally use Taylor 8mm Spiral Pro (they fit the retainers if you dremel the clips a little), others like MSD 8.5mm wires. Taylor has a custom fit wire set for the LT1/4 Vette. The price is ~$55 from Summit Racing and the wires are red so only an astute observer knows they're not OEM.
[Modified by 96GS#007, 9:24 PM 6/3/2003]
If the plugs are original, it's not unusual for them to lose the platinum pucks on the ground electrode. When this happens, the gap increases to ~.065 from .050. My last set of AC Delco double platinums had less than 40k miles on them. 6 of the 8 were missing their pucks when I pulled them. I use Denso Iridium IT20s now, but NGK TR55ix are also good.
Lastly, my experience is that you can get about 40k out of a set of stock GM plug wires. If you didn't buy the car new, you can tell if they're the original wires if each wire has the cylinder number printed on it. Only the original, installed in Bowling Green, plug wires have this. OEM wires sold over the counter at the dealer do not. I personally use Taylor 8mm Spiral Pro (they fit the retainers if you dremel the clips a little), others like MSD 8.5mm wires. Taylor has a custom fit wire set for the LT1/4 Vette. The price is ~$55 from Summit Racing and the wires are red so only an astute observer knows they're not OEM.
[Modified by 96GS#007, 9:24 PM 6/3/2003]
Team Owner
Joined: May 2002
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: Got the code read by a guy at Autozone...P0300... (96GS#007)
6 of the 8 were missing their pucks when I pulled them.
Le Mans Master
Joined: Jan 2000
Posts: 6,595
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From: Thornton CO
Re: Got the code read by a guy at Autozone...P0300... (DavidR)
How many miles are on the car? I wouldn't go replacing the Opti just yet, you have the GOOD OPTI (believe it or not). You can get 120,000+ miles out of the 95-96 Opti.
Thread Starter
Burning Brakes
Joined: Apr 1999
Posts: 1,161
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From: Texas
Re: Got the code read by a guy at Autozone...P0300... (Timmy!)
Timmy
the car has 82k on the odometer.
After doing a search on plugs and wires I decided to try Jim's suggestion above first.
Apparently NGK has recently changed their numbering system because every parts store I call for TR55ix plugs, the guy tells me that's a bad part number. They show a NGK 7164 that's iridium that works on an LT4 but I'm unsure if it's the exact same plug as the TR55ix. The NGK website only shows the TR55ix, not the 7164 number, they also apparently don't have list of part numbers for specific applications on their website. I was trying to confirm that TR55ix would indeed work on a LT4 car if I ever did find a store with them in stock. :confused:
still hunting...
dr
the car has 82k on the odometer.
After doing a search on plugs and wires I decided to try Jim's suggestion above first.
Apparently NGK has recently changed their numbering system because every parts store I call for TR55ix plugs, the guy tells me that's a bad part number. They show a NGK 7164 that's iridium that works on an LT4 but I'm unsure if it's the exact same plug as the TR55ix. The NGK website only shows the TR55ix, not the 7164 number, they also apparently don't have list of part numbers for specific applications on their website. I was trying to confirm that TR55ix would indeed work on a LT4 car if I ever did find a store with them in stock. :confused:
still hunting...
dr
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Joined: Mar 2001
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From: Whippany NJ
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St. Jude Donor '08-'09
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Re: Got the code read by a guy at Autozone...P0300... (DavidR)
1st off, p0300 is the code for random misfire. when that happened to me, my o2 sendors were the culprits. have them checked first before swapping optis unless you really need it.
I woould forget iridium plugs. Copper will give you the best performace. go with NGK TR55 they are excelent plugs and you wont be dissappointed! IMO
I woould forget iridium plugs. Copper will give you the best performace. go with NGK TR55 they are excelent plugs and you wont be dissappointed! IMO
Thread Starter
Burning Brakes
Joined: Apr 1999
Posts: 1,161
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From: Texas
Re: Got the code read by a guy at Autozone...P0300... (eamador11)
eamador11
thanks, I forgot to mention in my original post that I put a new cap and rotor on the opti at 50k when I replaced the water pump. Cleaned it up good while I was in there. I really didn't think it would be bad so soon (at 82k) but it seems to be the popular failure mechanism for most with my symptoms.
I'll see if I can get the O2's checked as well....
thanks
dr
Very nice car BTW !! I really like that front spoiler! :yesnod:
thanks, I forgot to mention in my original post that I put a new cap and rotor on the opti at 50k when I replaced the water pump. Cleaned it up good while I was in there. I really didn't think it would be bad so soon (at 82k) but it seems to be the popular failure mechanism for most with my symptoms.
I'll see if I can get the O2's checked as well....
thanks
dr
Very nice car BTW !! I really like that front spoiler! :yesnod:
