Howdy all.
My 2008 Cadillac CTS with the 3.6DI engine started to miss a little under hard acceleration yesterday and the P0300 and P0302 codes came up on my Tech 2. Sure enough, driving it with the Tech 2 connected and running the misfire graphic- it showed severe missing on the #2 cyl.
The car has just turned 52k miles and I was planning on changing the plugs anyhow around 60k miles since I've never ever gotten much more than that out of the OEM plugs. I know some of you have gotten 100k miles, but not me.
Now - I could just take it to the dealer since it is covered under warranty...but being a true BITOGer. I stay far away from dealers and would rather change out the plugs myself than have them only replace 1 plug under warranty.
So....I pull the #2 plug (lucky it is one of the one's you don't have to loosen the intake to get to) and it says AC DELCO 41-990....but it has the Bosch logo and Bosch plug # stamped in the steel part!! WHAT! I said - Bosch plugs in a GM car when so many here say they won't work on GM's LOL. Well- at 52k miles I would agree these plugs are awful. I thought for sure they would be iridium....but are just double platinums. So, I will first be switching coils tomorrow just to be sure it is not a bad coil (in which I will let GM pay for). If it proves the plug is bad, I will change them all out to Autolite double platinums and be done with it. I had also noted a slight miss on cyl #1 with the Tech 2 so I am guessing these plugs are done with and due changing.
Note: I did notice quite a bit of deposits on the plug. Maybe my preventative intake spray clean at each oil change to minimize any potential DI carbon issues fouled the plugs over time. Who knows...
My 2008 Cadillac CTS with the 3.6DI engine started to miss a little under hard acceleration yesterday and the P0300 and P0302 codes came up on my Tech 2. Sure enough, driving it with the Tech 2 connected and running the misfire graphic- it showed severe missing on the #2 cyl.
The car has just turned 52k miles and I was planning on changing the plugs anyhow around 60k miles since I've never ever gotten much more than that out of the OEM plugs. I know some of you have gotten 100k miles, but not me.
Now - I could just take it to the dealer since it is covered under warranty...but being a true BITOGer. I stay far away from dealers and would rather change out the plugs myself than have them only replace 1 plug under warranty.
So....I pull the #2 plug (lucky it is one of the one's you don't have to loosen the intake to get to) and it says AC DELCO 41-990....but it has the Bosch logo and Bosch plug # stamped in the steel part!! WHAT! I said - Bosch plugs in a GM car when so many here say they won't work on GM's LOL. Well- at 52k miles I would agree these plugs are awful. I thought for sure they would be iridium....but are just double platinums. So, I will first be switching coils tomorrow just to be sure it is not a bad coil (in which I will let GM pay for). If it proves the plug is bad, I will change them all out to Autolite double platinums and be done with it. I had also noted a slight miss on cyl #1 with the Tech 2 so I am guessing these plugs are done with and due changing.
Note: I did notice quite a bit of deposits on the plug. Maybe my preventative intake spray clean at each oil change to minimize any potential DI carbon issues fouled the plugs over time. Who knows...
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