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03 Ranger 3.0 OBD not ready for smog after drive cycle


Socal

Member
Joined
Feb 3, 2020
Messages
8
City
Socal
Vehicle Year
2003
Transmission
Automatic
Hope this is the right section to post. I'm just learning about cars so forgive my ignorance. I need some help to pass smog -- OBD is still not ready - oxygen sensor, oxygen sensor heater, evap, and cat are not completed. Expired tags for over a month so far :(.
I have gotten a new battery and have completed a few drive cycle attempts since then, maybe 3 ( looked at the ford drive cycle) after the new battery, about 200+ miles. Driving stop and go and at 55 on the freeway with hazards on, in socal... Smog guy checked the Fuel trim and STFT on both banks were identically +12.5, so running lean. He said maybe a vaccume leak, i have visually inspected vaccume hoses/lines, the PCV valve was replaced like 8 years ago, but have not checked this with smoke yet. There are no codes. Months ago i had a p0102 code but i replaced the MAF and cleaned my K&N air filter and it did not return. This was all pre - smog attempts, so im thinking i should clean the new maf again b/c of the fresh K&N oil in the air filter...? Maybe I need more drive cycles? Im gonna replace the cigarette lighter fuse just in case and get a new radiator cap. Any suggestions? Opinions? Truck has 97,000 milles and starts up great every time idles at under 1500 rpms at first ,then dips to around 1000, it vibrates a little but not a violent shake or anything.... no check engine light. Runs fine as far as i can tell but i dont drive that much. Thanks in advance for any tips. Hoping I don't have to just scrap my perfectly fine running truck because OBD monitors wont ready.

edit - I started the car and unplugged the IAC and the idle dropped to just above 500 rpms, like 600 rpms-ish - does this indate a vaccume leak as well?
 
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Yep I have that printed out and have been tryin to follow it each time. How excact do I need to be?
 
Trying to follow drive cycle "rules" is an insane and pointless task in my experience. Keep the gas tank around half to 3/4 full and drive normally. The system needs x amount of cold soak times that you simply can't force.

Btw change your freaking pcv valve for god sakes...

And as far as fuel trims, those numbers mean nothing without other info. They could be and probably are perfectly fine.

Unplugging the iac and having the idle drop like that is a good sign of no vac leaks.
 
I've driven countless customer cars to clear the monitors so they could pass NH inspection. This is what I would do:
Make sure there's over 1/4 tank of fuel and the cap is on tight.
Warm up the engine and go for a test drive
Get on the interstate and drive 10 minutes at 55-65 mph- I'd go 62 because any faster would mean going another 5-6 miles to the next exit.
Get off the highway and get on the entrance ramp to head back, accelerating at least 2/3 throttle to 60 mph. Coast back to a stop and repeat the 2/3 throttle acceleration.
Get off at the next exit and find a spot to stop and let the engine idle in drive for 2 minutes
Drive back to the shop through town stopping and taking off as many times as I could.
The Ford manual says to avoid turns and hills on the drive cycle, that's impossible here. We have so few straight sections of road that we name them, I live about a mile from West Canaan flat, Canaan Flat is a couple miles in the other direction, and Hammond's Flat is on the southern side of Canaan. My method almost always worked.
 
I've driven countless customer cars to clear the monitors so they could pass NH inspection. This is what I would do:
Make sure there's over 1/4 tank of fuel and the cap is on tight.
Warm up the engine and go for a test drive
Get on the interstate and drive 10 minutes at 55-65 mph- I'd go 62 because any faster would mean going another 5-6 miles to the next exit.
Get off the highway and get on the entrance ramp to head back, accelerating at least 2/3 throttle to 60 mph. Coast back to a stop and repeat the 2/3 throttle acceleration.
Get off at the next exit and find a spot to stop and let the engine idle in drive for 2 minutes
Drive back to the shop through town stopping and taking off as many times as I could.
The Ford manual says to avoid turns and hills on the drive cycle, that's impossible here. We have so few straight sections of road that we name them, I live about a mile from West Canaan flat, Canaan Flat is a couple miles in the other direction, and Hammond's Flat is on the southern side of Canaan. My method almost always worked.

Great description!! The Ford IDS diag computer has a process for this. Allows you to bypass the EVAP section, and clear the monitors. Most smog stations, will pass you with ONE monitor, uncleared.
 
OK thanks guys, I'm not givin up yet. I'll will keep tryin to drive cycle and use 19Walt93's tips. And the PCV valve was replaced in 2013, I inspected it and it still sucks and rattles, so I think its good.
 
Fuse 21 in engine fuse box, 10amp, is the KAM(keep alive memory) power for the PCM(computer), this fuse always has power and holds the "test results" in PCM Memory when key is off, so it doesn't have to retest at every startup

Have a look at it, if you pull it out you will have start over again

And................test battery voltage, 12.8v-12.3volts is a good battery, after it sits overnight, need to test batteries after they sit for at least 6 hours
If lower then when you start the engine the voltage can drop too low, and KAM power goes to low, so memory is cleared and OBD tests have to start over every startup
 
NH uses the Gordon Darby OBD II test system, a Ford with one "not ready" will fail. Several Asian cars will pass with up to 2 not readys and that never made sense to me.
 
NH uses the Gordon Darby OBD II test system, a Ford with one "not ready" will fail. Several Asian cars will pass with up to 2 not readys and that never made sense to me.

No, certainly doesn't, being that OBDII was to "standardize" this entire issue:cautious:
 
Obd2 is standardized for the most part but some cars have more systems monitored than necessary under different US or state smog rules. NJ allows up to 2 systems to not be complete as long as there are no permanent or pending codes.
 
I looked at fuse 21 (kam) in the engine w/out pullin it out, seemed ok. I will check the battery again, even though its new. I've been reading through the forums tryin to get a clue of what could be wrong. Did two more attempts at a drive cycle, tried to follow 19Walt93's, I'll try Jim's next, and still same 4 monitors not complete. Maybe the truck idles a little high (1000) even when warm? Also air intake temp reads a little high, like 110 and its only 65 outside. I don't kno if this means anything. Here's the diagnostics from smog place today after driving for 40+ mins... Maybe I should clean the IAC valve?
:( 20200205_123332.jpg

edit -With the IAC unplugged my car wouldn't start/dies instantly. idk what this means.
 
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After you clean it disconnect the battery for a few minutes to clear the memory- and don't unplug anything else- before the road test.
 
You test IAC valve while engine is warmed up and idling
THEN you unplug it and RPMs should drop to 500 or engine may even stall, either is GOOD, it means no vacuum leaks and IAC Valve is working, closing all the way

Computer opens IAC Valve all the way for starting the engine, if you unplug it and then try to start engine it won't have enough AIR to start and stay running
You could push down on "gas" pedal a bit to let in more air as needed
 

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