Corvette Z06 Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
1,281 Posts
Discussion Starter · #1 ·
Hey all,

Ive been having some codes being thrown quite often (P0172, P0175, P1431, P0300). I inspected the engine and found nothing wrong, no fuel injector wire chaffing or anything. I pulled the plugs and this is what I found. I did not pull plug from cylinders 5 or 8 for time sake. Please take note of the insulator color on plug 7. I put a scanner on the car and it said cylinder 7 was misfiring. Knowing the codes and seeing the plugs, anyone got an educated guess or know something else I could check or look up?



 

·
Registered
Joined
·
17,744 Posts
You might have a bad plug wire. Buy a new one or swap the wire with another cylinder and see if the problem moves. :cheers:
 

·
Registered
Joined
·
902 Posts
IT L GO said:
You might have a bad plug wire. Buy a new one or swap the wire with another cylinder and see if the problem moves. :cheers:
Like he said, Many times I have seen ignition wires fail shortly after being pulled off a plug. While you have the plugs out do a compression test then if the results are ok change the wires and plugs

Sabot
 

·
Moderator
Joined
·
21,378 Posts
P0172 Fuel Trim System Rich Bank 1
P0175 Fuel Trim System Rich Bank 2
P0300 Engine Misfire Detected

Just going with the highest probability. I've had my plug wires off more times than I can count and they have never given me a problem, that is, as long as you put them on correctly.
 

·
Registered
Joined
·
2,317 Posts
Just going with the highest probability. I've had my plug wires off more times than I can count and they have never given me a problem, that is, as long as you put them on correctly.[/QUOTE]


I agree with Jub ! Make sure the plug wires are snapped all the way on ! I know I've done it before on the rear cylinders !


Rob
 

·
Registered
Joined
·
1,281 Posts
Discussion Starter · #7 ·
Thanks for the replies guys. I've done the check my wires thing and reseated all of them and the problem persisted. The misfire cylinder was #7, hence the dark insulation around the electrode. I swapped the wire with the #5 cylinder to see if that fixes it. Next, im going to try swapping coil packs. Im guessing the rich situation is something im going to have to talk to my tuner about.
 

·
Moderator
Joined
·
21,378 Posts
You know, I think this comes with the territory when you have modified car. I've notice that my car runs rich at idle. I'm seeing a lot of soot in the exhaust. I also get misfire codes and MAP codes. It's not surprising to see fouled plugs and misfire codes with a cammed or S/C car. The ticket is a good tune or have them turned off, or both! IMHO of course. :D
 

·
Registered
Joined
·
3,212 Posts
My recollection is that #7 takes the worst of the oil in cars with Valley Cover seal leaks. The plug is certainly fouled. Maybe because it's Missing, either because of Wires or the Coil. Maybe, because you're sucking oil.
 

·
Registered
Joined
·
2,388 Posts
RocketSled said:
My recollection is that #7 takes the worst of the oil in cars with Valley Cover seal leaks. The plug is certainly fouled. Maybe because it's Missing, either because of Wires or the Coil. Maybe, because you're sucking oil.
If I'm standing in front of the car (facing the windshield) looking at the engine, what is the cylinder numbering order?

Why would cylinder #7 suck more from the PCV system?
 

·
Registered
Joined
·
1,273 Posts
Driver ft is #1
Driver side is 1,3,5,7
Pssgr is 2,4,6,8
 

·
Moderator
Joined
·
21,378 Posts
RocketSled said:
My recollection is that #7 takes the worst of the oil in cars with Valley Cover seal leaks. The plug is certainly fouled. Maybe because it's Missing, either because of Wires or the Coil. Maybe, because you're sucking oil.
How about TOO MUCH FUEL!

Oil fouled plugs are black and wet.

Plugs that don't fire usually don't have any color.

I have seen enough plugs in my day to know a "RICH" condition when I see one. That plug is running rich as in RICH!

http://www.users.bigpond.com/jack_stands/motorcycle_advice/bike_servicing/sparkplug_chart.html
 

·
Registered
Joined
·
58 Posts
I had the same P0172 code and fouled #7 plug after Anivenom H/C install. Greg figured it was a bad injector and replaced, no help. Checked compression, spark, injector flow etc. - all good. Pulled the valve cover and had a broken exhaust valve spring! thank god for putting in dual springs! Hope this isn't your problem but thought I'd throw it out there.
 
1 - 15 of 15 Posts
Top