Sebring 2.7 Sebring missfire and injector codes
 

Hi, have '02 Sebring convertible with 2.7 engine, 107k miles. Plugs replaced at 90k. Car started to misfire a few days ago. Checked codes and have 0305 misfire, cylinder #5 and 0205 injector circuit, cylinder #5. Problem only happens when engine is up to full temperature after running for 10 or 20 minutes. After cool down, engine starts and runs fine but misfires again when up to temperature after 10 to 20 minutes. Cycle repeats. Once it starts to misfire it continues until engine is shut off and cooled down. Also, when misfiring starts check engine light flashes. Seems to be heat related, but not really sure. Any ideas as to problem? Thanks for your help.

"0205 injector circuit, cylinder #5."

Kevin, thanks for your reply. Can you narrow the problem down a little bit. Do you think it's the injector? What parts make up the injector #5 circuit? Is there a way I can test this. I have a voltmeter and a consumer grade OBDII.

IF u want diog test u would need to buy a service manual it will walk u though all of that.
I only have stuff that u use the dealer scan tool and would be useless to you.

The injectors should measure about 13 to 16 ohms. You may be able to hear the injector clicking by touching the end of a screwdriver to the injector while the engine is idling and touching the handle to your ear.
Check and clean the connectors in the harness with electrical contact cleaner.
Can't hurt, might help.
The Haynes manual for your car has a whole chapter on the fuel system that discusses this.

Thanks for your replies. The only way to see or get at the injector and connector is to remove the plenum. If I'm going that far, I may as well replace the #5 injector just to be safe. Since this is a bit of work, do you guys feel it’s the injector or could it be something else? I'll also check out the Haynes manual. Thanks.

In looking at engine on both banks near the coils for #5 and #6 there's a green wire that goes to a small black device about a 3/4" x 3/8" to engine ground. Someone told me this is a capacitor. What is this for? Capacitors can be affected by heat. Could this be related to problem I have??

The capacitor in the system is to minimize radio interference. It's not likely to be the cause of your problems since it's tied to more than one cylinder.

Since injectors are hidden and access to wires at PCM are difficult to get at. In fact, everything in a Sebring is jammed packed into engine compartment.
I elected to bite the bullet and remove plenum and replace #5 injector. Old injector read about 13 ohms. Now I had that sinking feeling it was good and not the problem. Replace with new injector. Started engine and it still had misfire.(#&$%) Shut off and cleared all codes. Started engine again and it ran fine. It’s been running great for the last four day under all conditions, so I’m confident problem is solved with new injector. My belief is the injector coil was heat sensitive which caused an open when hot. I've seen this in my field of electronics when parts are heat sensitive and fail only when hot.
As to why it still misfired after initial injector replacement is a mystery. Maybe PCM had to reset? If I have time, one day I’ll put bad injector in an oven and heat it up then measure coil. Anyway, thanks again to everyone for your trouble shooting help. It was very helpful and greatly appreciated.