P0305 Cylinder 5 Misfire

[crespoh69]

Hello everyone, I'm hoping someone will be able to help me fix this issue I've been trying to fix. I've changed the plugs, the wires and have even swapped the #5 coil pack with the #3 coil pack to see if the code moves but the same code still comes up and the car will occasionally run rough. What's the next step I can take?

This is for a 99 Auto 6 cyl

 

[crespoh69]

Ahhh, I've been battling this for the past few months only my misfire is on #3.
Next, try swapping fuel injectors to see if the misfire moves. I did, but hasn't fixed the problem. If that doesn't work, try replacing O2 sensors (advice I received from this forum and most likely my next step). If these don't work, then...

...you may have a blown head gasket or cracked head. Symptom would be loss of coolant and/or coolant smell/white smoke from exhaust when starting the engine after it has been sitting for awhile. Pray this isn't the issue.

Word of Advice: Don't get too excited if the engine starts running well right after completing one of these steps. My engine ran well for a few weeks after each step I took: plugs, wires, coil pack swap, fuel injector swap. But, inevitably, the daggone misfire came back. Good luck to us both.

You know what I will try the O2 route as well because a few months prior to this I was also getting an O2 code but forget what it was exactly, it went away on it's own.

 

[FD7683]

I really hate to bump an ancient thread but cylinder #5 hasn't been very nice to me lately and its been troubling to diagnose the problem - new spark plug and coil pack made it in there but it did not fix the misfire. By throwing in Seafoam injector cleaner in the gas tank and pushing it hard, the stuttering did lessen a bit and its not as bad as before but its still doing it intermittently. I'm concluding injector #5 is failing.

I heard that aftermarket fuel injectors are junk. Would you guys recommend replacing or rebuilding the injector? For now, i'm going to throw in some more fuel injector cleaner and see if it helps it a bit more.

 

[spartacus]

I really hate to bump an ancient thread but cylinder #5 hasn't been very nice to me lately and its been troubling to diagnose the problem - new spark plug and coil pack made it in there but it did not fix the misfire. By throwing in Seafoam injector cleaner in the gas tank and pushing it hard, the stuttering did lessen a bit and its not as bad as before but its still doing it intermittently. I'm concluding injector #5 is failing.

I heard that aftermarket fuel injectors are junk. Would you guys recommend replacing or rebuilding the injector? For now, i'm going to throw in some more fuel injector cleaner and see if it helps it a bit more.

Replacement injector with an oem injector. I had issues with a refurbished injectors. Some say motorwest performance injectors are good but I don't know if they sell one. Normally it's a set of 6 or 4.

 

[FD7683]

Replacement injector with an oem injector. I had issues with a refurbished injectors. Some say motorwest performance injectors are good but I don't know if they sell one. Normally it's a set of 6 or 4.

Hmm, i'll have to look deeper into this. Thanks for the advice. All I heard from Motorwest is that they will just clean them.

 

[spartacus]

Hmm, i'll have to look deeper into this. Thanks for the advice. All I heard from Motorwest is that they will just clean them.

.

I am fairly sure they sell em. Check their site motorwestperformance.com.
if you want to get them cleaned and refurbished this guy in Colorado is the best imo.
Home