Bad cats will cause the HC to be out of wack, sometimes NOx also. Are the cats original? If it turns to be the cats it could be expensive.
OK, the old 5er just failed the Texas State Emissions Test. Car has 140k mi. on it, and has been very carefully maintained according to prescribed schedules. No codes thrown in a while and the most recent one was for an O2 sensor, so I put in two new ones from BMA about a year ago.
Here is the data from the test:
HC (PPM) 228 max allowed 112 FAIL
CO (%) 0.49 max allowed 0.62 PASS
CO2 (%) 14.5
O2 (%) 0.6
Nox (ppm) 1156 max allowed 829 FAIL
Dilution 14.99 need >6 PASS
Question is, what to do next? Seems like I am way out of range on Hydrocarbons, so is trying another testing facility worth the $40 ? Is there any way to do some troubleshooting on my own ? Car doesn't have OBDII, so there were no other data available. Or, do I just need to go to the local indy and have them diagnose ?
TIA
Robert Callaway
Dallas, TX
'94 530im 143k mi
'94 Land Cruiser FZJ-80 202k mi.
"If I could have back all the time and money I ever spent on cars.......I'd spend it all on cars."
Bad cats will cause the HC to be out of wack, sometimes NOx also. Are the cats original? If it turns to be the cats it could be expensive.
'01 540it, 6/01
'03 325i 5 speed, 9/02
'10 535ix. 9/09
'10 mini 6 speed
'15 mini countryman 6 speed
Yes, I am afraid it could be the cats, and yes they are very expensive. Last time I priced them they were about $1200 ea, IIRC. That is the very, very last thing I would be willing to replace. All other rocks will turned over first.
I just put some Redline Fuel System Cleaner in the car just now and will run it hard for a few days. It doesn't get a good workout in my normal commute to the office and back, so maybe there is some carbon build up going on. Also, if I understand the M60 motor, there is no EGR system, and the car relies on the cats to do a good bit of the work. I have a feeling the car sat too long before the test was performed and they were not really at proper temp. so getting them good and hot before the test could help a bit. I always run premium gas in it but we are in an area with up to 10% ethanol. Would that help or hurt?
Ideas ?
Thanks again.
Last edited by Super90; 04-03-2008 at 02:19 AM.
Robert Callaway
Dallas, TX
'94 530im 143k mi
'94 Land Cruiser FZJ-80 202k mi.
"If I could have back all the time and money I ever spent on cars.......I'd spend it all on cars."
and it will make some difference is oil is fresh,car(and cats) are hot....run some injector cleaner through too,just before you change the oil.
Gone but not forgotten
Yep, they were OE cats from BMA, but that was about four years ago when I priced them. Aftermarket cats for M60 cars were a bit dodgy back then and no one really recommended them.
Robert Callaway
Dallas, TX
'94 530im 143k mi
'94 Land Cruiser FZJ-80 202k mi.
"If I could have back all the time and money I ever spent on cars.......I'd spend it all on cars."
We'll do. Thanks !
Robert Callaway
Dallas, TX
'94 530im 143k mi
'94 Land Cruiser FZJ-80 202k mi.
"If I could have back all the time and money I ever spent on cars.......I'd spend it all on cars."
Is that $1200 for factory replacements? On my 525i I just use an aftermarket replacement and it passed just fine, and it was alot cheaper than the factory replacement cat.
That's the plan. Try the easy, cheap, obvious things first, then go try the test again within my 15 day period. If we fail again, we are going to the indy for a full diagnosis.
Funny thing is, the car has new O2 sensors, recent plugs and intake seals (13k mi.), I run only premium gas from known sources, only Mobil 1, change the filters frequently, she runs strong and idles smooth. And this is an original block M60.
I am just wondering if she needed a fuel system cleaning and that the cats were not at good operating temp. It sat for maybe 30 minutes before they did the test, it was about 65 degrees outside, and I wasn't driving her very hard before we showed up.
Keep the ideas coming ! Thanks fellas !
Robert Callaway
Dallas, TX
'94 530im 143k mi
'94 Land Cruiser FZJ-80 202k mi.
"If I could have back all the time and money I ever spent on cars.......I'd spend it all on cars."
If it's cats, go with magnaflow replacements - way cheaper and still very good.
My 530i failed TX emissions, too and there are all kinds of other reasons why it can happen with an older car. In my case, some solder joints on the DME had cracked, which gave erratic and intermittent control to the spark - I can't take credit for finding this out, but re-soldering things made it right.
The o2 sensors could still be bad, or you could have one or more corroded wiring connectors - often ground wires. Or a spark coil (or 2) could have gone a bit south, so giving weak spark.
I took mine to an indy shop here (Houston) where they have the equipment and know how to deal with this complex stuff - never the dealer.
Good luck.
I wouldnt bother going to the stupid expense of changing the cats when it is most likelly the lambda sensor which sits in the cats. Give that a go first it'll probably cost you less than £100 ($198)Originally Posted by Super90