p0354

[tigapaw]

have a 2005 ls v6 only code is p0354. replaced coil cleared code and code returned.
cleared code and swapped coils 4 and 5 to make sure new coil was not bad
code returned car rough idle in nuetral or drive with foot on the brake.
any idea what to do next,did not replace plug

 

[cobey]

I had a similar situation when I had my first tackling of the coils on my LS. The concensus of this forum seems to be to swap all coils and plugs with OEM Motorcraft because if they aren't failing now, they will be soon. This has been covered pretty extensively in the forum, so a quick search should find more info for you. Good Luck

 

[joegr]

That code indicates a problem with the primary circuit of that coil. Check the wiring. One of the wires should have +12V all the time the engine is running. The other should pulse to ground. Check the wiring all the way back to the PCM. Also check the connector at the coil. It could be a bad PCM, but I would make sure that it isn't wiring first.

After you get this resolved, the suggestion to change all the coils and all the spark plugs at once is a very good one.

 

[tigapaw]

already got the Motorcraft DG528 coils coming all 6 ,plugs,and intake gasket
will start on the wires next

 

[tigapaw]

lol now i got a p0301 but all coils and plugs and gaskets soon
and i promise to never be cheap again
getting the motorcaft stuff and not the 6 coils for $77

 

[Gus_Mahn]

I've seen some primary coil codes caused by bad PCM's Hopefully it's in the coil not the PCM.

 

[tigapaw]

going to install new coils and plugs in my 2005 ls v6. what else should i do while i'm in there?
pcv and elbow?
intake manifold gaskets? lower set only or kit that includes plenum set?
valve cover gaskets?

 

[LS4me]

going to install new coils and plugs in my 2005 ls v6. what else should i do while i'm in there?
pcv and elbow?
intake manifold gaskets? lower set only or kit that includes plenum set?
valve cover gaskets?

I'm pretty sure the 2nd gen doesn't have the PCV (elbow) hose issue like the 1st gen. On our old V6 I was able to reuse the old upper plenum gasket, 3 times. Depending on the miles, you may be able to wait on the valve cover gaskets.

 

[tigapaw]

only 48000 miles