Check Engine Warning Light

Dakota 04, 4.7 L, 32000miles

Autozone code error P0302
Definition:
BBCylinder misfire detected-cylinder number 2
Explanation:

BBThe powertrain control module monitors the crankshaft
speed and has detected a misfire condition.
Probable cause:
Definition:
BB1. Ignition system fault-spark plug(s)
Ignition wires, coil
BB2. Vacuum Leak.
Bb3. Injector fault.
Bb4. High or low fuel pressure.

Installed new gapped plugs. ( all 8 ),
side note: air filter replaced also.
Light still on.

Does the test really show that it is indeed the # 2 Coil
or just a 1 in 8 guess?
Is their a way to check that coil?

Any help is greatly appreciated.

The code merely means that the PCM has detected a misfire in cylinder #2. You have to figure out whether it was caused by lack of spark or lack or fuel and then the cause of the problem.




78 Corvette Pace Car For Sale-18k mi orig-Florida

Not well versed with the newer coils or injectors,
is there a way to check either of these?

So it is indeed # 2, then this is where I need find if the coil or injector


Thank you!

I've given you specific instructions to resolve your problem. If this is beyond your abilities, then your just going to have to have a shop do it for you. It's not an easy vehicle to work on at all.




78 Corvette Pace Car For Sale-18k mi orig-Florida

Jack; As HT stated, the problem is with #2 cylinder. It is the front one, on the passenger side of the engine. This is a 'coil over plug' engine, meaning each cylinder has it's own coil. It also has an injector for each cylinder. You could have a coil problem, a defective spark plug, an injector problem, a vacuum leak affecting that particular cylinder, valve problem, ect. It is going to take some diagnostics to find the problem. A shop with a gas analyzer should be able to figure it out rather easily. A compression test of that cylinder might help.
Loren
SW WA

I have to apologize here. I confused this question with another one I was working on at the same time that had a coil problem that I gave specific instruction for.




78 Corvette Pace Car For Sale-18k mi orig-Florida

If you know which coil is the #2 I would try placing it into another cylinder , clear your codes and drive the truck wait for MIL to come on and rescan the truck if code jumps to that cylinder then you know for sure your problem its the coil............................

>>I confused this question with another one I was working on at the same time<< LOL. OPD. (Old pharts disease). Welcome to the club.
Loren
SW WA

In Reply To

Swaptronics.....Not a bad diag method, I've been known to use it a time or 2... . I would also move the plug to a different cylinder.......


(This post was edited by Sidom on Sep 9, 2009, 6:04 PM)

No Problem, about the confusion with the other problem you were answering,
at my age I goof more than I care to admit.

1. Plugs were changed out, # 2 did not look fouled to my eye. center electrode rounded slightly to side electrode
However gap was maybe about .044
Have attached similar plug picture ( but this is Not my plug ) My plug slight Goldish or yellowish color on ceramic insulator on # 2 plug

2. now that I know that code is correct, and it is indeed #2 cylinder.

3. went back to store and cleared code, been 8.9 miles no error as yet.
they stated that code sometimes clears itself or not, anyway it is cleared.
seems it should either clear or not clear code, just my way of thinking.

4. If code returns, I will swap it with another cylinder, clear code, see if problem presents itself on a different cylinder. Swaptronics

5. if code returns to # 2, next step is to look at # 2 injector

6. Have not heard a vacuum leak.

Thanks to all who answered.

Code returned after 90 miles. ( all plugs replaced, before 90 miles )

Have swapped # 2 Coil with # 4 Coil and have cleared code, see if that is the problem.

If Code comes back with # 2 misfire, ( thus possible injector problem ) then I guess I'll have to see if that is still covered under the ( power train warranty )32k miles less than 7 years.

Jack