[mark jeansonne]

I have a 2001 P38. Runs fine, but code 1172 keeps coming up, "running rich". A good suggestion I got was to change plugs. Anyone recommend good upgrade for spark plug replacment? Manual calls for Champion #RC11PYPB4, I assume there are better replacements today.

 

[SID]

I have a 2001 P38. Runs fine, but code 1172 keeps coming up, "running rich". A good suggestion I got was to change plugs. Anyone recommend good upgrade for spark plug replacment? Manual calls for Champion #RC11PYPB4, I assume there are better replacements today.

I was told that the Champion plugs were the best for my 4.6. Low tech engine = low tech plugs..... some thing to do with the high amount of power from the coil packs I think.

Could not find the part number as in the manual from Champion here in the UK as now replaced with part number RN11YCC. So thats what I have got in mine.

Engine is also a bit on the rich side and I thought the plugs would help to burn all the fuel but no, after a good run at 70mph they are just as sotty as the ngk's that were in there before.......Maybe I need to get the engine management values reset at a dealer?

SID.

 

[allyv8]

A set of NGK BPR6ES will do fine - no need for anything clever.

 

[david despain]

champion 318 also known as RC12MC4

 

[big-t]

I was thinking the same thing" witch spark plugs to use in my 01, 4.6 HSE " and I went to Google and typed in," How do spark plugs work". I was amazed at the wealth of info availiable and how helpful the posts were. Give it a try, You'll be happy you did. Good luck, Big-T.

 

[Doctor Leo]

Your truck will run rough on NGK plugs same with Bosch. The OEM Champions are a good choice, but going to the Champion Iridium plugs is your best bet. In both my P38's I ran the iridiums and it ran smooth and never stumbled in idle or in hard acceleration. I would also do a set of hotter aftermarket HP wires. Which you can find info on the main site about. Good luck and stay away from NGK and Bosch plugs.

 

[GEMS 4.0]

I've used these particular NGKs in my 1997 GEMS 4.0 for two years and find they are rubbish, as the exhaust is always sooty despite having clean air filter and good ht leads and coil pack etc and now the engine misfires at idle and some plugs are covered in soot! I got them in Halfords as they recommended them, but have researched since and find they are NOT equivalent to the OEM Champions RN11YCCO which are supposed to be used!

 

[Reinhoud]

I'll give this a try in my Disco with 4.6, can't getting it idling smooth... It runs on Bosch, got Champions in the P38, and that engine runs like a dream, so incredibly smooth..