Random Misfire Code PO300??
12-04-2008, 09:56 PM
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Random Misfire Code PO300?? Guys i got my 97 t/a ws6 a4 last saturday and its registering a p0300 code . Its giving me shitty mpg and throttle response. Car has 112,000 on the clock and according to the last owner car sat for a year in a storage. In november he replaced the distributor cap, wires , plugs , new fuel filter, and a new k&n filter for the ram air. Were do i start to look for this random missfire??? any help would be appreciated thanks oscar
12-06-2008, 01:14 PM
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I would go over what he replace already make sure it was done right and with quality parts. Any paperwork??? Next id check to make sure im getting spark and fuel at each cylinder, and definitely check the compression on it to make sure your internal parts are working right..... id probably run it on a dyno to see what type of readings your getting, that can tell you a lot also.
12-06-2008, 06:11 PM
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Guys i got my 97 t/a ws6 a4 last saturday and its registering a p0300 code . Its giving me shitty mpg and throttle response. Car has 112,000 on the clock and according to the last owner car sat for a year in a storage. In november he replaced the distributor cap, wires , plugs , new fuel filter, and a new k&n filter for the ram air. Were do i start to look for this random missfire??? any help would be appreciated thanks oscar
I think the guy is blowing smoke up your A. Random multiple misfire is usually plugs or wires. Have someone change them again.
12-07-2008, 07:53 PM
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thanks Thanks for the advice and i looked at the spark plug wires and they dont look new at all . The only thind that looks new and worked on is the optispark cap cause theres is some new RTV in the waterpump. I also noticed that on both sides the wires are tied together with zip ties.
1. Will this cause a crossfire between the wires?
2. What wires and plugs do you guys recomend for a non nitrous motor?
3. What do you guys think of these wire set?
http://cgi.ebay.com/ebaymotors/_Car-...1%7C240%3A1318
1. Will this cause a crossfire between the wires?
2. What wires and plugs do you guys recomend for a non nitrous motor?
3. What do you guys think of these wire set?
http://cgi.ebay.com/ebaymotors/_Car-...1%7C240%3A1318
12-08-2008, 09:06 PM
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it is possible to get a cross fire so you wanna get a divider to seperate the wires, and they come cheap if not free, so why not? I would go wit NGK PLUGS...MSD WIRES. That wire set seems justifiable for a TA but MSD would be my choice, I haven't heard too much about vision wires, but if you know someone that can back em up then run wit it, but I would go MSD.
12-09-2008, 03:40 PM
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I don't know about those wires. 10.2mm is awfully big and sounds like overkill to me. I know people will disagree with me on this one, but go to your local NAPA store and get a Belden wire set for around $85. That's a great price for good wires.
12-09-2008, 05:42 PM
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Jegs wire set What do you guys think about Jegs 8mm wire set looks good only 30 dlls?
http://www.jegs.com/photos/55540200callout.jpg
http://www.jegs.com/photos/55540200callout.jpg
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12-10-2008, 06:01 PM
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Misfire... Man, I will be totally honest...I own a 98 Firebird with a V6. I had this problem in cylinder 6 and one other cylinder (would jump back and forth). I found out that the cat was bad on it...HONEST! Replaced that and went out for a drive and 2 complete engine cycles later and Service Engine Soon light went out and went back to riding smooth. I also had a problem before with cheap plugs...(don't ask, long story) but you just cant buy any plugs or wires for these engines. High Output means just that. Hope this helps.
12-10-2008, 07:59 PM
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What do you guys think about Jegs 8mm wire set looks good only 30 dlls?
http://www.jegs.com/photos/55540200callout.jpg
http://www.jegs.com/photos/55540200callout.jpg
12-10-2008, 08:28 PM
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8.5 Well i decided to go with the JEGS 8,5 MM wire set and hope for the best, i got some good feed backs from a couple of members. Ill post up pics when i get em and details when i install em .
http://www.jegs.com/photos/555-yellowwires.gif
http://www.jegs.com/photos/555-yellowwires.gif
12-10-2008, 08:39 PM
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.. Hey mast my car feels good man but the problem is when go wide open throttle its doesnt respond at the BEGGINING like it should ?? As far as the miss i dont feel it at all , it idles smooth exept when i put it in Drive its starts to shake ,,, any help guys ,,,
12-11-2008, 06:39 PM
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See, mine would do that at times to on a wide open stomp. I took it out on a side road and held down to see if some carbon would "shake off" so to speak and held down to about 110 MPH. After the little test it started acting a little better until half the trip home and started coming back again. All the mathematics in the exhaust really is important to these engines. I, myself didn't realize how much it could really effect the performance until I took it to the exhaust shop. Basically with a clog cat yea, your engine will idle fine depending on how clogged it really is until the time you need the full response from the engine. Then that's when the emissions and MAF kicks in and says "uh, hell no you are chokin the **** out of me". Basically, it's like me asking you to run a 2-mile lap and me sitting in front of you with 16 cigars blowing in your face. I won't say that a cat is for sure the problem but that is where I would start just from the sound of it. PLUG WIRES & PLUGS is where I would start next. If it's shooting off a code just post it on this posting and I'm sure someone can tell you in a heartbeat what it is or where exactly to look. PM me if you need some help.
12-18-2008, 07:22 PM
#13
I've been wrestling with a miss fire problem for months! I changed the plugs about 3 times. I did find one that was cracked. New MSD wires. Also, it got real bad when the PCV vacuum lines eroded. Spray some starter fluid near the vacuum lines and notice if the idle changes. Have a fire extinguisher handy just to be safe. I had my PCV vacuum lines replaced and the car ran fine for about 1 or 2 cycles, now my miss fire is back! I'll try replacing one wire at a time, then plugs again, then check vacuum lines, then reset battery, then try dyno....then burn car if that don't work. LOL! Under hard acceleration is when I notice it and it only gives me a PO300 code too. The car is amazing accept for this annoying miss fire. WTF!
12-18-2008, 08:36 PM
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I've been wrestling with a miss fire problem for months! I changed the plugs about 3 times. I did find one that was cracked. New MSD wires. Also, it got real bad when the PCV vacuum lines eroded. Spray some starter fluid near the vacuum lines and notice if the idle changes. Have a fire extinguisher handy just to be safe. I had my PCV vacuum lines replaced and the car ran fine for about 1 or 2 cycles, now my miss fire is back! I'll try replacing one wire at a time, then plugs again, then check vacuum lines, then reset battery, then try dyno....then burn car if that don't work. LOL! Under hard acceleration is when I notice it and it only gives me a PO300 code too. The car is amazing accept for this annoying miss fire. WTF!
12-19-2008, 10:37 AM
#15
It's an LS1. Drives me crazy!!! I'll start checking wires soon.
12-19-2008, 07:20 PM
#16
Ran good today, slight miss at the end of the day. I think it's the wires. I have some spare wires, and will check resistance on MSD wires. Didn't replace them today....was having fun while it ran good!
12-23-2008, 02:39 PM
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Probably the Optispark. I know we are quick to blame the opti, but when I bought my car it also had a random misfire (and threw a code). It needed new plugs and wires. After that the code went away but it was still misfiring, just not as bad. I replaced the opti and it runs perfect now. And you saying it does it when it's wet out makes me think thats probably what it is.