Is there a BMW Error code P0470? '99 BMW 528i with 104,000 mi has intermittent "Service Engine Soon" light. On advice of dealer, had secondary air pump & valve replaced. Dealer also said spark plugs needed to be replaced, which I did myself ($36 parts & my labor vs. $312 dealer). Light came back and has been intermittent on a few days, off a few days. Came back on, and AutoZone printout is for error code P0470. This isn't listed in my Bentley manual for 52TU/54 engine. As an SAE code, it seems to point (at least for Fords) to an exhaust pressure (EP) sensor, possibly due to a short circuit on the signal return...I have no idea where this is, or how to DIY...is it time to go back to the dealer? O2 sensors were replaced about 2 yrs ago.
That code may not be right. You can't trust universal code readers on BMW sometimes. You need to have someone with a real scanner give you the code. Any indy BMW shop with a GT1, Autologic, or even a Snap On MT2500 with BMW software can read the codes properly. BTW, what plugs did you buy? That price seems low for what these cars take (I know the NGK BKR6EQUP plugs that you are supposed to use are like $14 each, but not sure about the BOSCH FGR7DQP.)
Paul, How do I find an indy BMW shop in the Newport RI area who would have the code reader? There were two shops I know of, but both have gone out of business in the last two years. Thanks. The plugs were Bosh Platinum +4s, but not BMW OEM stamped.
You don't need to PM me. You can try the phone book, your local BMWCCA chapter, or the internet to find shops. http://www.bimmershops.com/ shows none in RI, but there may be one nearby. Platinum +4 plugs are OK, but if they are not the number I listed above, then they are not the ones that are recommended by BMW for the car. My gut says that while they fit, they are probably not the ones you want. Might that cause your CEL to come on? Maybe.