Emissions testing cycle?
 

Picked up a "new to me" E53 last weekend. Having difficulty getting it *ready* to pass our local emissions inspection. It isn't failing, but simply reporting "not ready". I've put about 250 miles on it, mix of highway and commuting, all the emissions testing center has said is "drive it some more" but that is a little risky when I can't get the license plates until it passes. Anyone know what the *actual* driving cycle for a 2001 E53 (5sp manual, 3.0) is? I've found a couple of things on the internet but so far had no luck with them.

FWIW, I DO have an OBD2 ready and I can check for the VA emissions test myself before going to the shop, but still trying to get the "not ready" status to finally clear itself.

Are there any codes? I think if it reports "not ready" it's either there is a problem or the problem has been fixed and not enough drive cycle has happened yet. What did previous owner say ?

Haven't contacted previous owner yet, he's on vacation (was leaving when I picked up the car last week, and I'm about 95% certain his location doesn't require emissions testing.

Codes... not irrelevant of course, but not *directly* tied to the emissions either. Again, it isn't FAILING emissions, just reporting that it is not ready. I cleared the codes last night in frustration (which reset the emissions readiness!), but mostly because I didn't know how old any of the codes might have been and was trying to get a clear baseline. Put about 60-70 miles on the car early this morning and so far none have come back. Emissions tests that report not ready are mostly centered around cat. converter, o2 sensor heating circuit, and evap. leak test. I'll go back down to the car in a bit and check.

Basically, any time the battery is disconnected, it resets the readiness test. I'm assuming the battery was disconnected during some of the prep work getting it ready to sell, I'm just trying to figure out what the cycle is that it wants me to complete. I found the one below online, but don't know that it is specifically for the E53, so trying to get as specific as I can since I'm not overly comfortable driving it around without plates.

We don't have emissions testing here either so I don't have much more advice other than maybe doing a search on here because I know this has been talked about before. Maybe someone more familiar with the ready status will chime in. Can't you get plates with a grace period for emissions testing ??

Afraid that both safety inspection and (for my county) emissions are required to register it.

That being said, safety is done, most of the emissions items seem to be either cat. converter or o2 sensor related. Here's current status:

I've seen cats not set for a long time on various models and makes. I recommend a new thermostat. Check the coolant level. Use a laser thermometer. Is one cat hotter than the other?

FWIW, had one more code clear over the weekend (O2 sensor) after about 100 miles of driving. So I have 3 left:
Cat Converter
Evap System
O2 sensor heater.

I'm not opposed to replacing a thermostat, but what does that have to do with the cat. converter? I'm not making the connection there....

Picked up a set of 02 sensors, figured I'd either replace them on the X5, or use them on my kid's E39 that we're restoring, so that may be my next step. I'll try to get under it in the next day or two and check cat converter temps. I did log the output of all 4 02 sensors for a little bit of driving (and idling) yesterday, and noticed one of the pre-cat sensors was fluctuating a LOT more than the other. Car has about 130,000 miles on it, so they COULD be original, not sure. Figure replacing them isn't going to hurt anything other than possibly my knuckles.

You need to check for "trouble" codes with a scanner that can read all of them. Readiness won't set if there are problems. Yes, for sure thermostat has a lot to do with emissions and could affect the readiness for any test that needs to see the engine temp.
If you have a good scan tool you can run the evap system test manually. (Maybe even do a oxygen sensor test manually too but I'm not sure about that one.)

I'll check for codes in a bit. I have both a Foxwell and a phone-based app, saw some intermittent codes but can't recall off top of my head. Only one I remember was for the O2 sensor, which passed the emissions readiness test so I didn't pay much attention to it.

Has anyone ever been able to fix the o2 heater issue?[emoji848] I think every e53 has that error....[emoji28]

Sent from Embassy network using Tapatalk

Thermostats keep the engine hot enough to heat cats. If a thermostat is not working properly, at highway speeds the engine runs cooler but won't set codes. A thermostat maintains engine temp constant for NOx burning. The instrument gauge doesn't swing enough to see temp changes. For it's age, a new thermostat is good maintenance. Does it have OEM plugs in it? Or updated single filament iridium plugs? Does voltage swing up and down on front O2 sensors. Voltage should swing. The rear O2 sensors should read a more constant voltage. Some scanners can read cat temps. Are both cat temps close in readings?

@EODguy
I don't think I've ever seen a O2 heater code on mine, should be a lot easier to track down than a mixture code. I'm pretty sure there are some good threads here on that.

I've never seen an O2 heater code on my '01 (not sure if it even HAS heated O2 sensors), either. Last time I got it inspected, I was able to get all the emission monitors to set, except for EVAP. Having one monitor not set is OK for my year model in Texas, though. It only took me a 5 mile drive (not following any "drive cycle" regimen) to get the others to set.

On the other hand, a few years ago, it took me almost 500 miles of driving to get my '04 Chevy 2500HD (6L gas) to set the monitors. Even after I closely followed the prescribed "GM Drive Cycle" at least 10 times. I drove it several days, with many key on/off cycles, but with no luck. Finally, all but the EVAP monitor set. I had replaced one downstream O2 sensor, and the evap filter, prior to that episode.

On other cars & trucks, resetting the emissions monitors has usually taken about 50 miles doing the GM drive cycle, after repairs and code clearing (most of my vehicles have been GM). The quick reset of the monitors in the X5 was a pleasant surprise. Can't wait to see what my wife's Lexus will do, when/if I need to reset the monitors.

Sent from my SM-G965U using Tapatalk

It does. There will be four wires going to each sensor - two of these are the heating element.

Yep, the heat circuit has a seperate ground that I think often gets overlooked so probably a good thing to check if one has heater code issues.

The EVAP one always takes the longest. It has to be above 37° Fahrenheit and you have to let it stand overnight and it has to have either like a full tank or empty tank or something. It's taken me forever to get it to turn on on the f30. E53 it still took a few days of random driving. The cycle they mention in ISTA, doesn't work. Even if all the sensors and everything are tip top it doesn't work.

Thanks all. I managed to get temp. tags today good for 30 days, so I can actually DRIVE the thing without worrying about getting pulled over, MUCH easier for trying to get the last codes to clear!

What *SHOULD* the coolant temps be for "normal" driving? I know the temp gauge is borderline useless, but I'm driving with a live OBD2 readout on the phone so I'm normally seeing it fairly steady at about 201 F.

I also replaced both front O2 sensors yesterday during my lunch break, haven't had a chance to get under the car to deal with the 2 rear. Front sensors are cycling heavily when I log them, rears are relatively steady at 0.4-0.5.

Now that I have the "luxury" of the 30 day tags, I'll probably drive it for a day or two, see how it does, and then replace the rear o2 sensors and clear any codes and re-start the process if needed.

Buy a cheap gas cap. Take the o ring off and put it on. Or flip your gas cap ring over. I've done this to several cars for EVAP codes. If the gas cap o ring is good enough, it will work to tighten up the seal. Flipping the o ring on mine worked for a while. Eventually, I took a seal off a new gas cap. No EVAP codes have appeared for two years.

201 is right on the money. It will move up and down between 198 and 203. And when you get it on the freeway the system will turn the t-stat heater on and the temp drops into the 180's.