I read somewhere that a flashing CEL means multiple misfires. I figured that I was getting misfires because I am running rich under boost (10:1). So today, I took the car up to 4K slowly without going into boost and the flashing CEL reappeared. The A/F ratio at the time was right around 14.7. I did it like 5 times. Every time I hit about 4K, I got a flashing CEL.
It doesn't seem to matter if I am boosting or not. And the A/F ratio doesn't seem to matter because it has done it while running rich, and while running stoich. Another thing to note is that it seems to do it more often when it is cooler outside (50 degrees F).
For plugs I have AC Delco's non-platinum, 1 step colder. I tried gapping them at .06, then at .04, and now they are at .03.
I'm not sure what the problem is, but whatever it is, my car has never felt "right" since the S/C. For a boosted car, it seems really doggish and slow. Anyone have any ideas or things I could check? Thanks.
2010 Subaru Impreza WRX Limited
1999 Cavalier Z24 Supercharged
1999 Grand AM SE (Beater Car)
1997 GMC Sierra
2007 Honda CBR 600RR
2005 Honda TRX450R
the p0300 code does not come on just because of misfiring but also because if the stock ecu sees a drastic amount of energy being pulled through the stock coils to burn the fuel.
I suggest trying to work on your af's all over and try some new plugs, gap them to around .035
LE61T PTE6262 Powered 
also you might want to replace the spark plug boots ( the springs) you'll have to get them from GM, i had a simular problem and it was the springs that was bad,this might save you alot of money instead of taking it to the shop
if at first you don't succeed,you should probably give up
i got some extra boot/spring spark plug things if you want to give them a whirl.
im having this same problem. I get a flashing cel when im at wot, ive already checked the plugs and i have them gapped at .045 and i replaced all of my spark boots even though the code only showed cylinder one as having the missfire. but im still getting a cel
I am going to try changing the plugs tonight and gap them at .035 and see what happens. I hope its something as simple as that or just new springs, bu the way things are going, I kinda doubt it.
Jake, I'll let you know how the spark plugs turn out. If they don't do the trick, I'll try your boots/springs if you don't mind.
2010 Subaru Impreza WRX Limited
1999 Cavalier Z24 Supercharged
1999 Grand AM SE (Beater Car)
1997 GMC Sierra
2007 Honda CBR 600RR
2005 Honda TRX450R
pending how much boost you are running, you may need to gap down to 26 thou, this will stop any spark blow out issues you may be having.. it is something to try :shrug
HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED
I don't have a boost gauge at the moment, but I am running the stock 2.4L S/C puley. So I'd imagine I'm only running between 3-5 psi max. I will try gapping them a lil closer and see what happens.
Is there any downside to gapping the plugs too close?
2010 Subaru Impreza WRX Limited
1999 Cavalier Z24 Supercharged
1999 Grand AM SE (Beater Car)
1997 GMC Sierra
2007 Honda CBR 600RR
2005 Honda TRX450R
Its probably from running pig rich try doing what QBE recommended and try some new springs
Also check the igntion coils themselves, one may be weak and on it's way out.
14.330 @ 96.37mph
or if the white COIL pack housing has carbon tracking on it. had it happen to me years ago.
BlownBlackZ wrote:Also check the igntion coils themselves, one may be weak and on it's way out.
I've been meaning to boost this exact question.
Ive *had* this problem and it went away (almost..cept every once in awhile while on it thru 4th to high speeds) with the .35 plugs. Now i have them to .032 and tried .030 and while I go out onthe back roads to *test and log my tunes.. i always get a p0300 misfire. NOthing shows up on the logs with hpt. No knock, no weird hiccups, nothing. It seemed to go away with the car running a 11.8-11.9 afr, but it has shown to be a .2-.3 tenths slower consistantly with the rich afr. I bumped it up to 12.1-12.2 and it seems (iill find out this friday) that the top end it back ot were it was with the stock 310s maxing out and not being able to keep up.
Now, BBz, how would i go about checking the coils themselves? seems plausible since its beginning to happen more often rather then every once in awhile. ALTHOUGH, it usually (even at its best) would have a pending p0300 at one or two of the runs (of a 5-6 runs night)while at the track.
Thanks.
Nate
Evolution of Cavyboy-->C22t--> C24na--->c24s/c
1995 Cavalier W/2k1 Engine
GM S/C 13.940@99.78pmh w/2.068 60ft
better yet, has anybody proven to reduce or get rid of the misfire with an msd set up??
Evolution of Cavyboy-->C22t--> C24na--->c24s/c
1995 Cavalier W/2k1 Engine
GM S/C 13.940@99.78pmh w/2.068 60ft
Z Speed Cavi wrote:Its probably from running pig rich try doing what QBE recommended and try some new springs
Like I said before, it will misfire even when it is running stoich 14.7, NOT rich, and NOT under boost. So it doesn't seem to matter if its running rich or not.
Edited 1 time(s). Last edited Wednesday, August 23, 2006 3:59 PM
2010 Subaru Impreza WRX Limited
1999 Cavalier Z24 Supercharged
1999 Grand AM SE (Beater Car)
1997 GMC Sierra
2007 Honda CBR 600RR
2005 Honda TRX450R
Luke Heier wrote:Z Speed Cavi wrote:Its probably from running pig rich try doing what QBE recommended and try some new springs
Like I said before, it will misfire even when it is running stoich 14.7, NOT rich, and NOT under boost. So it doesn't seem to matter if its running rich or not.
yikes.. u def have a problem if it happens when not under boost.
again...how do we test the coils to see if they are bad? should try that first.
Nate
Evolution of Cavyboy-->C22t--> C24na--->c24s/c
1995 Cavalier W/2k1 Engine
GM S/C 13.940@99.78pmh w/2.068 60ft
Something is telling me your coil pack is going bad.
I too had the flashing when I first got the S/C (twice in the same hour). Never saw it again.
I am using the RKS boots for bout a year and love them. I am using the kit's spark plugs at 0.050 since installation in 2004 too.
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-----The orginal Mr.Goodwrench on the JBO since 11/99-----
i never ever had a flashing missfire code. could have been when i cleared my egr code each time the computer didnt care about what other codes were there.
anyways, depends when i get rid of the s/c kit, but if you are in town i can let you try my #5 rapid fire plugs. might work better for you.
Well, I've got an extra coil pack and the stock plugs that came with the S/C kit. I think I'll try that tomorrow morning before work and see how that turns out. I'll keep everyone updated.
2010 Subaru Impreza WRX Limited
1999 Cavalier Z24 Supercharged
1999 Grand AM SE (Beater Car)
1997 GMC Sierra
2007 Honda CBR 600RR
2005 Honda TRX450R
yeah i went to the auto parts store and bought a new coil back, replaced it right in the parking lot, no more cel.
Well, I put new AC Delco plugs in, gapped them to .035, put a different coil pack on, and the flashing CEL is still there. It's EXACTLY 4250 RPM's or above when the flashing CEL comes on.
When I took out the old plugs, I found that the ceramic part on one of them was cracked. I figured that along with bad coil packs would be the issue, but I guess not.
Anyone have any other ideas???
2010 Subaru Impreza WRX Limited
1999 Cavalier Z24 Supercharged
1999 Grand AM SE (Beater Car)
1997 GMC Sierra
2007 Honda CBR 600RR
2005 Honda TRX450R
have you had the code read, when mine flashed for a while but then just staid on so i had it read and i figured out exactly which cylinder was having the missfire.
A flashing CEL just means theirs a pending code, not necessarily a hard random misfire code. Scan the car and see what pending code you have, it may even tell you a specific cylinder. If you have access to a Tech 2 you can see a freeze frame when the code was set.
Well, I don't have access to a Tech2, so thats kinda not an option. I will try to get my hands on a code reader and see what it says. Last time (which was a whiel ago) it was cyl #1 misfire.
2010 Subaru Impreza WRX Limited
1999 Cavalier Z24 Supercharged
1999 Grand AM SE (Beater Car)
1997 GMC Sierra
2007 Honda CBR 600RR
2005 Honda TRX450R
mmmm... i got msd today, with a set of used coil packs, so will see if that gets rid of my misfire Cell.. although i do notice when i get a rough launch it usually goes off without fail. But if its a nice launch doesn't go on. HOWEVER, either way, theres always roughly the same amount of knock off the line with i drop it. weird.
Nate
Evolution of Cavyboy-->C22t--> C24na--->c24s/c
1995 Cavalier W/2k1 Engine
GM S/C 13.940@99.78pmh w/2.068 60ft
