Recently my car has developed a misfire. It throws code P0174 (system too lean bank 2) and P0308 (cylinder 8 misfire). It all started when I was driving home Thursday. It misses all through the rev range. No oil burning, no coolant burning, no oil in coolant or vice versa, and no soot on the exhaust tips, not even any black smoke. I have not found any vacuum leaks, fuel pressure is good (~40psi).
Now this only happens when the car is at optimal operating temperature. There is no misfire on a cold start or for about 45mins after. Then all of a sudden the car starts shaking and is down on power.
The car is a 97 cobra.
Luke Reed
Change plugs and go from there
Ian Morgan
I did the plugs today. (Probably should have mentioned that) also the plug boots don't have any signs of cracking, rotting, burning, or anything. Same with the wires. Although, I think the wires are still stock.
Julian Perez
Swap the wire with one from a different cylinder. (both end) if the misfire doesn't jump to that cylinder it could be the fuel injector. If it was both banks it might be a clogged fuel filter. It could be an air leak after the maf sensor or vacuum leak somewhere.
Oliver Powell
I had an issue with persistent misfires that would start when the car hit operating temperature and it ended up being a valve issue.
Christopher Baker
>valve issue
Pls no
Nathaniel Cox
I change wires with every plug change. To eliminate the mystery.
Isaac Gutierrez
>mfw I also have a 4.6 that just started having these exact same issues (shuddering and missing without any visible fluid/exhaust issues) and the same code (cyl 8 misfire) Let us pray together.
Nathaniel Green
Just doing a little googling it seems like this is a fairly common problem for the 4.6 so you're probably not SOL quite yet. You know what they say Ford stands for don't ya. It stands for fix it again tony.
Luke Stewart
Change in fuel?
Had a similar problem when I was forced to use 89 octane in an 87 octane engine. Missing due to timing issues with higher octane fuel. Only ever happened at operating temp, and had loss of power associated with it. Once tank was driven empty and filled on proper fuel, it resolved.
Blake Roberts
Well that day it started I did get a full tank of gas. And it was in NJ where you can't pump it yourself. If it was bad gas wouldn't it be misfiring on more than one cylinder?
Benjamin Cruz
Don't know, but it will cause weird engine issues. Mine just kind of intermittently missed. I was like 16 or 17 at the time, so I don't remember well.
You can always drain the tank and get a fresh fill and see if that fixes it. Problem solved.
Aiden Flores
Also, not being able to pump your own is fucking retarded. Wife and I drove through Oregon, it's weird.
Jose Sanchez
irrelevant to current post but i need help. i didnt want to open a new thread for my question
So i was changing the hose for the radiator because it broke and i well i replace it and placed things back together. but there was one hose that i couldn't recall where it went. can you guys help me out. i have a 1996 nissan altima.
thanks for the help, i really appreciate it
Elijah Rogers
Trans breather hose, I believe. That is where it goes.
James Peterson
>Fill radiator. >Watch for gushing water. >Attach hose to whatever water came out of.
Angel Baker
my nigga.
Julian Perez
yeah i think that's what it is because it was close to the air filter when it was moved. i am concerned that it has to be connected but my friend did say it wasnt connected when i was working on it.
it was close to the air filter thing. i had to remove that section to get to the hose that i needed to replace
thanks fellas. but if anyone thinks otherwise i'd appreciate the info.
Hunter Davis
How many miles?
Jack Evans
Check any rubber elbows on the pcv system under the hood. The heat causes them to soften up and they suck themselves closed or develop a leak and pop a lean code. Since both codes pertain to bank 2, I'd look around that side of the engine for any rotten hoses.
Leo Parker
I'm not sure. The odometer is broken. Maybe 120k+.
Ryan Powell
There is carbon blocking one of the intake valves. Easiest fix is to.go to the to of a steep hill. Go about 20mph turn the engine off, then turn key back to the click before the starter motor. press the accelerator fully down to the floor stick the car in second and drop the clutch.
This will blow out all the gunk with a bang!
Be aware when the car is off you lose power assisted steering and brakes so dont do it when other people are around
Ayden Johnson
OP here
I have found the problem. I swapped the #8 injector with #5 and the misfire has migrated with the injector.