kornfreak_401

iTrader: (77)

I was going down the highway passing cars in 4th at 6,000 rpm and all of a sudden inbetween changes I would get big puffs of smoke come out the back like i blew up when i would go back into 6th. SES lights up for a while then a few minutes later starts to blink. I run the OBDII Scanner and pulls up P0307 #7 cylinder misfire.

1) I replaced the plug. Old plug looked good, only had about 3-5 months of life. cleared the codes and ran engine, still sloppy and puts out P0307 again.

2) Swapped entire coil pack rail with ls1powerhouse's rail. Inspected old pack and looked good. cleared the codes and ran engine, still sloppy and puts out P0307 again.

3) Swapped coil pack #7 pack on my rail with the first one. cleared the codes and ran engine. P0307 DAMN!!!

WHAT CAN I DO NOW??? Seriously people, I need help.

My car is running really sloppy and is smoking like crazy.

How do I run a fuel ingector test on #7?

Do ya'll think it's my valve spring seals? I've put about 16-17K miles since i got the car last FEB.

How can I tell if my seals are bad if I take the valve cover off?

Jerry

Gilbert@Ace Racing

Well it sounds as if you have damaged the engine. The only way to knwo for sure is to do a few tests. One is to do a compression test, check all cylinders not just #7, start there but check them all. If only one cylinder is affected then you know there is and internal issue, valve seals do not cause low compression. The other is to do a cylinder leak down test, both tests require specialized tools.

You cannot check valve stem seals by simply removing the valve cover. The springs must be removed to be able to effectively determine the seals integrity. Besides, a defective valve seal will not allow enough oil to foul a new plug. The seal would need to be missing for that much oil to be going through it. And even if it were passing that much oil it would not be an immediate, right after you start the engine symptom.

"How do I run a fuel ingector test on #7" Not likely either, it would have to be stuck open. If it were you would get more than a misfire code ordinarilly. Besides, the plug would be dripping wet with fuel.

Sounds to me like you have burned a piston, ring or valve. Maybe a bad head gasket as well. You need a qualified technician to diagnose it.
g

kornfreak_401

iTrader: (77)

thanks, i'll look it to it

badboyracingws6

iTrader: (9)

That happened to my old truck and it ended up being a head gasket. Good luck on that man, let me know if I can help you out in any way.

Squirrelmaster

iTrader: (2)

I had that same code on my truck (started the day I bought it) and tried everything you did and more. I cleared it about a dozen times with no luck in figuring out what it was until I started getting a misfire on cylinder #8. Turned out my injectors were screwed, my fuel filter had blown out (blew out an hour after I bought the truck ), and all the sand that had formerly been in my fuel tank (long story ) ended up in my injectors and rails. However, I think you have a much more serious problem if you're smoking as much as you say you are. Good luck.

Tom

SSilverSSurfer

iTrader: (8)

damn jerry hope you figure it out

LS1Aggie09

iTrader: (25)

+1 on figuring it out...you think that could be the cause of the smoke you have been having for a while?

Overboosted

iTrader: (14)

Sounds like a cracked piston, or rings are screwed. Had the same problem myself once upon a time...

kornfreak_401

iTrader: (77)

well thanks guys. I'll figure it out. i guess this means heads/cam/springs/gasgets after all. vette's gonna have to way for a couple of months.

It's weird because i have great oil pressure and the rpm run really good. once i drive you can tell theres something wrong...

anything else?

A&M drty brd

sounds a lot like what my car has been doing (not sure what the code has been) , but my SES light hasnt blinked. its just stays solid. i got it cleared at a local shop earlier this week. hopefully i'll find out tomorrow morning what it is when i take it to MTI

88GT&69ss

What color is the smoke? Like real white or does it have some blue in it? Just curious

kornfreak_401

iTrader: (77)

NO not really white. more like blueish/grayish...

Speaking of... Jeff tunes my car. He can't seem to narrow down why in the hell i still keep running rich!! any ideas? i have new plugs, O2's, clean K&N WTF? I can't affor to be driving up there every week you know what i mean?


thanks

Jerry

Overboosted

iTrader: (14)

Are your 02s hooked up on the correct sides?

kornfreak_401

iTrader: (77)

yes. wait what do you mean anyways?

01WS6/tamu

iTrader: (37)

Have you tried washing the maf with some carb cleaner for your rich condition. How far - are your lt and st fuel trim values running.

01WS6/tamu

iTrader: (37)

If she has good spark and fuel supply it's gotta be internal. I am assuming you do not have cats on it. I had a f-car in the shop about a month ago that had 5 and 7 misfire dtc's and it drove me up a wall until I dropped the crossover and it went away the cat was beginning to fail and it was partially plugged.

tsench

iTrader: (15)

hey check your injector 2 fuse i have the same problem but mine missfire on cylinder 3 and my injector 1 fuse is out check that out and see what happen

kornfreak_401

iTrader: (77)

maf mo. trim's i'll find out tomorrow. what should i look for/be at?

kornfreak_401

iTrader: (77)

i'll check my fuses also...

thanks guys

Jerry

kornfreak_401

iTrader: (77)

bump..