Emissions system not ready to be tested

LeVeL

LeVeL

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Early in September I went to the dealership because they seem to be the only ones capable of correctly balancing my wheels. While there they offered to do my inspection and I agreed. They came back after a while claiming that the system isn't ready to test and showed me a printout that said that it was reset 0mi ago. My battery was last disconnected 2000mi prior to this (yes, I keep records), I haven't had a single CEL in the years that I've owned this car, so I'm guessing a tech disconnected my battery for some reason. After several weeks and 820mi it still wasn't ready!

I decided to reset the whole system again and disconnected the battery. After a couple of weeks of driving, this morning I followed a drive cycle procedure* I found online and it still says EGR and O2 sensor (not heater, that one is fine) are incomplete. Including the test loop posted above, I've done ~460mi since I reset the battery.

Again, no CELs, car drives fine although I've had some minor idle surges for a while, gas mileage seems normal (maybe 1mpg off but I can't be sure)... What's the deal? Bad cat? Bad O2 sensor? Computer acting up? Already got harassed by a cop with nothing better to do over my rejected inspection sticker.




*I didn't follow it to the T but I did complete each step. After ~15min on the highway I hit traffic and had to slow way down. Made up the two minutes I was going slow for by driving an extra 2-3min at 55mph. Around town GPS put me on a road where I could cruise steady at 45mph so after a few minutes of that I got back on the highway, drove normal (75mph) for 15min, then got onto local roads near my house and drove around for 20min.
 
Which vehicle is this on? Also for most drive cycles, you MUST match conditions exactly or the computer ends it. How old is the battery? Have you done a PID check to see if the temperature sensor is reading accurately (because if it isn't, a lot of things won't happen)?

Also, some I/M systems won't reset if the ambient temperatures are too low when you attempt the drive cycle.
 
If the car in question is the TL, that drive cycle is generic. Here is something that smells a lot more like the Acura drive cycle for the car.

The vehicle should be driven approximately 7.5 miles within a period of approx. 23 minutes (1372 seconds) from a cold start. However, due to manufacture variations, it is necessary to perform only as much of the Drive Cycle as is necessary to reset the required monitors to a "Ready" status. Operate the throttle smoothly to obtain best results. Do not shut the engine off during the drive cycle.
Step 1 (Engine Cold) Start engine, idle 20 seconds. Accelerate gradually and drive at 20-25 mph for 1 minute, varying speed.
Step 2 Accelerate gradually to 32 mph within 35 seconds. Decelerate to 0 mph in 10 seconds. Idle for 40 seconds.
Step 3 Accelerate at part throttle to 25 mph in 10 seconds. Cruise at 17-25 mph for 15 seconds. Accelerate gradually to 57 mph in 45 seconds. Cruise at 50-56 mph for 1 minute. Decelerate gradually to 0 mph in 40 seconds. Idle for 15 seconds.
Step 4 Accelerate at part throttle to 36 mph and maintain for 10 seconds. Decelerate to 0 mph in 15 seconds. Idle for 5 seconds.
Step 5 Accelerate to 30 mph and back to 0 mph within 30 seconds. Idle for 20 seconds.
Step 6 Accelerate to 36 mph in 20 seconds. Drive at 35 mph for 20 seconds. Decelerate to 0 mph in 15 seconds. Idle 5 seconds.
Step 7 Accelerate gradually to 26 mph and decelerate to 0 within 40 seconds. Idle 15 seconds.
Step 8 Accelerate to 27 mph in 40 seconds. Decelerate to 0 mph in 10 seconds. Idle 25 seconds.
Step 9 Accelerate to 26 mph in 15 seconds, maintain speed for 10 seconds, decelerate to 0 mph in 10 seconds. Idle 15 seconds.
Step 10 Accelerate to 23 mph in 20 seconds, decelerate to 0.5 mph in 10 seconds (no complete stop). Accelerate to 28 mph and back to 0 mph (momentary stop 1 second) within 35 seconds.
Step 11 Accelerate gradually to 34 mph in 45 seconds. Vary speed between 34 and 19 mph for 2 minutes. Decelerate from 25 to 0 mph in 25 seconds. Idle for 5 seconds.
Step 12 Accelerate to 29 mph in 15 seconds, decelerate gradually to 0 mph in 45 seconds. Idle for 30 seconds.
Step 13 Accelerate gradually to 28 mph and back to 0 mph (momentary stop 1 second) within 50 seconds. Accelerate gradually to 27 mph and back to 0 mph within 55 seconds. Idle for 15 seconds.
Step 14 Accelerate to 24 mph and back to 0 mph within 18 seconds. Idle for 10 seconds. Accelerate gradually to 22 mph and back to 0 mph within 50 seconds. Idle for 8 seconds.
Step 15 Accelerate gradually to 30 mph within 50 seconds. Decelerate to 0 mph in 10 seconds. Idle for 25 seconds.
Step 16 Accelerate to 23 mph and back to 0 mph within 30 seconds. Idle for 10 seconds.
Step 17 Repeat steps 1 - 16 once again. Recheck the status of the "Readiness Monitors".

NOTE: Remember, clearing DTC's or interrupting power to the ECM after the readiness monitors have been reset to "Ready" will require that the Drive Cycle be repeated.
Click to expand...
 
Guess what? Still not done.

Brought it to a local garage that I trust. They cleaned out the EGR but O2 and EGR sensor cycles are still incomplete. They ruled out O2 sensors and focused on the unstable idle instead. They determined that the throttle position sensor is ready at 7% open when idle really should be under 2% so the ECU basically never recognizes true idle so the monitors don't run their cycles. They did an idle relearn and it now reads correctly at ~1.7% open at idle but not it's not holding the idle steady. They disconnected the battery for 12hrs and that didn't help either. They're calling in a Honda tech who can "reprogram the idle" with some sort of specialized Honda software but he won't be in until Monday.

For now I got my car back and the idle is doing crazy things. Say I'm rolling up to a stop sign and take it out of gear when it's at 3k rpm - it stays at 3k rpm even though it's in neutral. I have to use the transmission to slow the engine down basically and once it's below 2k or so it falls down to regular idle when it's out of gear. I've never seen anything like this and it makes me miss cable throttles.

On a brighter note, I'm absolutely in love with my TL after driving the loaner car for a week.
 
Unstable idle like that is often traced to a vacuum/boost leak, no matter if it is a cable throttle or drive by wire. On older cars, it can also be traced to a bad idle-up solenoid or idle air controller, or a bad ECU. Worn throttle bodies are also an option. On DBW cars, once vacuum/boost leaks are eliminated as a potential cause, you only have three options - bad throttle body assembly or parts thereof, bad wiring or bad computer.
 
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