S70 T5 OBDII Monitors not ready for emissions

I have a 99 S70 T5 It is inspection time and with the new OBDII emissions based test I can not have any check engine codes. About 6 months ago I had the Check engine light and checked the code.

It was Fuel rich Bank 1. I replaced the Front O2 Sensor with an OEM sensor - Bosch I believe. About a month later the light came back on. I lived with it. But now I need it to pass inspection.

I checked the codes and had the P0172 error. Same thing. I started to check the vacuum lines and could not find any obvious problems. I cleaned the wires on the MAF sensor.

Still the same error. I cleared the code and now have 3 monitors that are not ready. O2, Catalyst and Evap System. I think you can have no more than 2 monitors not ready for the OBDII emissions test. I ran it about 15 minutes this evening and still they did not reset. I will let it cool and run it again tomorrow.

Any ideas on what else to check? I read about a small vacuum elbow near the power steering pump but I could not find it on my T5.

Oh, when I start it cold it runs very ruff for about 15 seconds.

Thanks Pal

Reply to
Pal
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You definately have a problem if its running rough at cold start. All the 5 cylinders should fire up almost instanltly and smoothly at cold start. It sounds as its running rich- does the exhaust smell excessively of fuel? I'd be looking at the coolant temp sensor to begin with...

Tim..

Reply to
Tim (Remove NOSPAM.

Replacing the oxygen sensor is not the thing to do for P0172. The most likely causes are vacuum leaks, fuel pressure or injector problems or a bad air mass sensor. Once the computer is "reset", (i.e. codes cleared, battery changed) it has to go through a thorough check of all systems, (called a "trip") twice for the readiness code to be set to "yes".

To set readiness codes, first turn off your A/C. A/C coming on will cause tests to abort. Resetting the check engine light the "proper way" with a Volvo tool will minimize the number of checks that need to be done.

After the computer is reset, the flywheel adaptation must first be done. This adaptation only occurs during coasting, the computer analyses the tolerances in the cage or teeth on the flywheel so it knows exactly when each cylinder is at top dead center. This is used for misfire diagnostics. You need to do several decelerations from speed (coasting). Without the special Volvo tool you have no way of knowing when this has been completed, but 5 or 6 from 100 km/hr (60 mph) to 40 km/hr (25 mph) should be enough. A slight downhill will help.

The Trip

Obviously a road with little traffic and a good shoulder where you can pull off easily would be preferable to complete this cycle. The times given are minimum, allowing a little longer won't hurt.

Start engine, with the coolant temperature between 29 and 49 degrees Celsius. Make sure the A/C is off. Gear selector in Drive Drive at 1500-2000 rpm for 6 minutes Idle engine in Drive for 70 seconds (Fuel trim adaptive functions are being tested here) Drive at 1500-2000 rpm for 6 minutes Idle engine in Drive for 70 seconds (Air pump functions are being tested here) Accelerate gently to at least 45 mph, (75 km/hr), drive at 1800-2200 rpm for 5 minutes Idle engine in Drive for 70 seconds (Evap leakage (gas cap) functions are being tested here) Accelerate gently to at least 45 mph, (75 km/hr), drive at 1800-2200 rpm for 4 minutes Now the instruction sheet I have does not specify, but I believe you should shift to neutral for the next step Rev engine to 1500 rpm, hold for 10 sec, return to idle for 10 sec. Repeat at least 3 more times. (Idle air adaptation needs to come to idle at least 7 times to be set to ready)

Now if everything worked out OK, you have just completed one trip. Turn the car off, and allow the coolant temperature to drop between 29 and 49 degrees Celsius, and repeat. If you have the fancy Volvo scan tool you can monitor this stuff, otherwise you're flying blind.

And while this may look like a very unfunny joke, I'm afraid it isn't.

Reply to
Mike F

If this is a MA7 system (electronic throttle) you wont have a MAF- this system uses a MAP sensor.

What if its a manual Mike?

Tim..

Reply to
Tim (Remove NOSPAM.

Well, I didn't compose this, just copied it. You'll have to do this part in neutral, I guess. And ME7 injection still uses a MAF sensor.

Reply to
Mike F

Ahh then my Haynes BOL is not telling the truth- they claim the ME7 uses a MAP sensor.

Tim..

Reply to
Tim (Remove NOSPAM.

Bosch ME7 uses both a MAF and a MAP sensor. (And and intake air temp sensor and a air pressure sensor, lots of scope for problems!)

Reply to
OBD

Ahharrr! We were both right then! hehe

Tim..

Reply to
Tim (Remove NOSPAM.

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