Cali smog question
Lead Driver
Joined: Dec 2006
Posts: 7,092
Likes: 145
From: San Diego, CA
They can detect tuners on newer trucks but not ours, especially a chip. It just plugs in and the PCM defaults to the chip like business as usual.
I don't know how they detect tuners specifically. Something to do with some flag/bit getting set/activated when something gets uploaded to the PCM including when you return it to stock programming. The smog shop sees this "bit" set and you fail. I understand the concept but don't know the technicalities of it. Regardless, ours don't have that flag problem.
As far as electronically I've not had a problem with tuning as I have a PCM flashed with a custom tune and a Hydra. My 6-position chip wasn't an issue either. The shop can't detect any of that by plugging into the OBDII (bad news - our trucks get smog checked, good news - our trucks are not fully OBDII compliant).
The physical aspect is more of a hold-your-breath-and-hope-(s)he-doesn't-look-under-the-dash-near-the-parking-brake. The cord is the only thing you can't hide. My 6-pos chip had an unmarked **** on the dash that the tech did not see/care about and I put my Hydra controller in my pocket and tucked the ribbon inside the dash. The only thing noticeable on the dash was a piece of velcro that he never asked about. If he would have asked I would have told him that it was for something convenient (pen, list, tech accessory) so that I would have it handy and not lose it.
I don't know how they detect tuners specifically. Something to do with some flag/bit getting set/activated when something gets uploaded to the PCM including when you return it to stock programming. The smog shop sees this "bit" set and you fail. I understand the concept but don't know the technicalities of it. Regardless, ours don't have that flag problem.
As far as electronically I've not had a problem with tuning as I have a PCM flashed with a custom tune and a Hydra. My 6-position chip wasn't an issue either. The shop can't detect any of that by plugging into the OBDII (bad news - our trucks get smog checked, good news - our trucks are not fully OBDII compliant).
The physical aspect is more of a hold-your-breath-and-hope-(s)he-doesn't-look-under-the-dash-near-the-parking-brake. The cord is the only thing you can't hide. My 6-pos chip had an unmarked **** on the dash that the tech did not see/care about and I put my Hydra controller in my pocket and tucked the ribbon inside the dash. The only thing noticeable on the dash was a piece of velcro that he never asked about. If he would have asked I would have told him that it was for something convenient (pen, list, tech accessory) so that I would have it handy and not lose it.
Lead Driver
Joined: Dec 2006
Posts: 7,092
Likes: 145
From: San Diego, CA
My boost fooler passed no problem.
I did the standard ribbon out from between the upper and lower dash pieces to the left of the steering wheel with the head velcro’d to the upper dash. I pulled the ribbon out of the head, put the head in my pocket, and tucked the ribbon back into the dash. Took me all of 30 seconds to do (obviously I had the engine off and key out of the ignition any time I connect/disconnect the controller head).
Don’t worry about the tunes. The Hydra will stay in whatever setting you have it in until you plug the controller back in.
You can leave it hooked up and take your chances but I’d already failed once and didn’t want to take any chances for round 2.
Obviously the easiest way to ensure you pass is completely remove the Hydra but I don’t have that option. I have single shot injectors and the PCM flash I have is too smoky. Lesson learned: get the tune dialed in THEN have it flashed to the PCM.
I did the standard ribbon out from between the upper and lower dash pieces to the left of the steering wheel with the head velcro’d to the upper dash. I pulled the ribbon out of the head, put the head in my pocket, and tucked the ribbon back into the dash. Took me all of 30 seconds to do (obviously I had the engine off and key out of the ignition any time I connect/disconnect the controller head).
Don’t worry about the tunes. The Hydra will stay in whatever setting you have it in until you plug the controller back in.
You can leave it hooked up and take your chances but I’d already failed once and didn’t want to take any chances for round 2.
Obviously the easiest way to ensure you pass is completely remove the Hydra but I don’t have that option. I have single shot injectors and the PCM flash I have is too smoky. Lesson learned: get the tune dialed in THEN have it flashed to the PCM.
Senior User
Joined: Jul 2018
Posts: 107
Likes: 0
They can detect tuners on newer trucks but not ours, especially a chip. It just plugs in and the PCM defaults to the chip like business as usual.
I don't know how they detect tuners specifically. Something to do with some flag/bit getting set/activated when something gets uploaded to the PCM including when you return it to stock programming. The smog shop sees this "bit" set and you fail. I understand the concept but don't know the technicalities of it. Regardless, ours don't have that flag problem.
As far as electronically I've not had a problem with tuning as I have a PCM flashed with a custom tune and a Hydra. My 6-position chip wasn't an issue either. The shop can't detect any of that by plugging into the OBDII (bad news - our trucks get smog checked, good news - our trucks are not fully OBDII compliant).
The physical aspect is more of a hold-your-breath-and-hope-(s)he-doesn't-look-under-the-dash-near-the-parking-brake. The cord is the only thing you can't hide. My 6-pos chip had an unmarked **** on the dash that the tech did not see/care about and I put my Hydra controller in my pocket and tucked the ribbon inside the dash. The only thing noticeable on the dash was a piece of velcro that he never asked about. If he would have asked I would have told him that it was for something convenient (pen, list, tech accessory) so that I would have it handy and not lose it.
I don't know how they detect tuners specifically. Something to do with some flag/bit getting set/activated when something gets uploaded to the PCM including when you return it to stock programming. The smog shop sees this "bit" set and you fail. I understand the concept but don't know the technicalities of it. Regardless, ours don't have that flag problem.
As far as electronically I've not had a problem with tuning as I have a PCM flashed with a custom tune and a Hydra. My 6-position chip wasn't an issue either. The shop can't detect any of that by plugging into the OBDII (bad news - our trucks get smog checked, good news - our trucks are not fully OBDII compliant).
The physical aspect is more of a hold-your-breath-and-hope-(s)he-doesn't-look-under-the-dash-near-the-parking-brake. The cord is the only thing you can't hide. My 6-pos chip had an unmarked **** on the dash that the tech did not see/care about and I put my Hydra controller in my pocket and tucked the ribbon inside the dash. The only thing noticeable on the dash was a piece of velcro that he never asked about. If he would have asked I would have told him that it was for something convenient (pen, list, tech accessory) so that I would have it handy and not lose it.
this is great information as I was looking at getting the hydra chip. Thank you.
Lead Driver
Joined: Apr 2011
Posts: 8,259
Likes: 346
From: Northern California
First step to understanding your challenge is to grasp why you failed.
he didn’t fail you because you had a tunner, he likely had no idea you had a tunner.
you failed because as soon as he plugged into your OBD port his scanner looks for 2 things.
1. Misfire monitor
2. comprehensive monitor
both of these must be “ ready” or you fail.
there is a very detailed Drive Cycle and set of events that have to happen before the computer will set the status to ready so you can pass smog.
typically a engine that is operating within the prescribe parameters of “smog legal” will set the status as ready within a 100 miles of typical driving but since you have recently driven a few thousand miles clearly your engine is not running within CA smog spec.
your next step is to figure out what is out of spec. If you have Forscan or the ability to monitor your PID’s while you drive I can point you in the right direction.
he didn’t fail you because you had a tunner, he likely had no idea you had a tunner.
you failed because as soon as he plugged into your OBD port his scanner looks for 2 things.
1. Misfire monitor
2. comprehensive monitor
both of these must be “ ready” or you fail.
there is a very detailed Drive Cycle and set of events that have to happen before the computer will set the status to ready so you can pass smog.
typically a engine that is operating within the prescribe parameters of “smog legal” will set the status as ready within a 100 miles of typical driving but since you have recently driven a few thousand miles clearly your engine is not running within CA smog spec.
your next step is to figure out what is out of spec. If you have Forscan or the ability to monitor your PID’s while you drive I can point you in the right direction.
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Lead Driver
Joined: Apr 2011
Posts: 8,259
Likes: 346
From: Northern California
here is an abbreviated portion of the required drive cycle and the part that modified and runner trucks often can't pass.
The crux of the drive cycle is step 3c and the part modified 7.3 typically fail is the MFDES which is the "Mass Fuel Demand" PID or how much fuel is being delivered by each injector...
7.3 Drive Cycle
1.Key on. Do not crank until the WAIT TO START or at least 10 seconds
2.Start the engine. Idle in PARK or NEUTRAL for 40 seconds.
3.Under load, accessories on, OVERDRIVE off to run in 3gear
b. Accelerate steadily to third gear and hold 1500 rpm for 3 seconds.
c. Accelerate 35 mph to 65 mph with MFDES @
Minimum of 37 mg above 1500 rpm for 11 seconds
Minimum of 37 mg above 2300 rpm for 6 seconds
Repeat 3x
4.Drive in fourth gear continuously for 60 seconds
b. Accelerate steadily from a full stop to fourth gear and then return to a full stop.
Repeat 10x
5. Before continuing, EOT must exceed 60C (140F).
6.Idle the vehicle for 20 seconds in PARK or NEUTRAL.
MFDES must remain below 12 mg for 11 consecutive seconds
7.Key off.
8.Start the engine. Idle in PARK or NEUTRAL for 40 seconds.
9.Check monitors
** The only parameters that apply to 7.3L diesel applications are CCNT, IAT, LOAD, MAP, MIL, RPM and VSS.
what this means is if you have over size tires and the computer doesn't know it, or your tuner has altered the MAP sensor reading ( which they do ) then the calculations for the MFDES will be off and your Comphrensive Monitors will not reset to the ready status.
bottom Line is unless your engine is running within parameters you will not pass smog, 2 years ago they tightened the restrictions and test procedure on Diesels,, they used to allow 1 monitor to not be ready and now the tolerance is zero.....
The crux of the drive cycle is step 3c and the part modified 7.3 typically fail is the MFDES which is the "Mass Fuel Demand" PID or how much fuel is being delivered by each injector...
7.3 Drive Cycle
1.Key on. Do not crank until the WAIT TO START or at least 10 seconds
2.Start the engine. Idle in PARK or NEUTRAL for 40 seconds.
3.Under load, accessories on, OVERDRIVE off to run in 3gear
b. Accelerate steadily to third gear and hold 1500 rpm for 3 seconds.
c. Accelerate 35 mph to 65 mph with MFDES @
Minimum of 37 mg above 1500 rpm for 11 seconds
Minimum of 37 mg above 2300 rpm for 6 seconds
Repeat 3x
4.Drive in fourth gear continuously for 60 seconds
b. Accelerate steadily from a full stop to fourth gear and then return to a full stop.
Repeat 10x
5. Before continuing, EOT must exceed 60C (140F).
6.Idle the vehicle for 20 seconds in PARK or NEUTRAL.
MFDES must remain below 12 mg for 11 consecutive seconds
7.Key off.
8.Start the engine. Idle in PARK or NEUTRAL for 40 seconds.
9.Check monitors
** The only parameters that apply to 7.3L diesel applications are CCNT, IAT, LOAD, MAP, MIL, RPM and VSS.
what this means is if you have over size tires and the computer doesn't know it, or your tuner has altered the MAP sensor reading ( which they do ) then the calculations for the MFDES will be off and your Comphrensive Monitors will not reset to the ready status.
bottom Line is unless your engine is running within parameters you will not pass smog, 2 years ago they tightened the restrictions and test procedure on Diesels,, they used to allow 1 monitor to not be ready and now the tolerance is zero.....
Lead Driver
Joined: Apr 2011
Posts: 8,259
Likes: 346
From: Northern California
Although it will usually through a p1211 DTC low fuel pressure at WOT can also prevent the injectors to deliver the prescribed 37mg at the correct RPM - MAP load.
a minimum of 45 psi is required at WOT and the only way to know that is to run a fuel psi gauge into the cab and test drive.
it is easier then it sounds, Tap into the fuel bowl with a -4 ORB to 1/4 NPT fitting and run a nylon hose to your test gauge, ( a cheap o harbor freight works just fine.
procedures below.... if you fail to maintain 45 psi at WOT it is typically a fuel pressure regulator in the fuel bowl.....riff raff and others sell the motorcraft rebuild kit.
7.3 Fuel Pressure Test
8c. Electric Fuel Pump
a. Measure Fuel at Fuel Bowl Test Port Spec . 45 psig WOT >42 psig
b. Measure at fuel outlet from electric fuel pump should be 51 ± 4.5 PSI @ idle.
c. Road Test- engine at full load condition 42 PSIG MINIMUM*
d. If fuel pressure fails low, go to step 8d.
e. If pressure is above min. spec, replace right check valve.
8d. Electric Fuel Pump Inlet Restriction.
a. If fuel line is restricted above 6 Hg, check for: blockage between pump and fuel tank.
b. If fuel line is not restricted, inspect regulator valve condition and for debris, If OK replace pump
a minimum of 45 psi is required at WOT and the only way to know that is to run a fuel psi gauge into the cab and test drive.
it is easier then it sounds, Tap into the fuel bowl with a -4 ORB to 1/4 NPT fitting and run a nylon hose to your test gauge, ( a cheap o harbor freight works just fine.
procedures below.... if you fail to maintain 45 psi at WOT it is typically a fuel pressure regulator in the fuel bowl.....riff raff and others sell the motorcraft rebuild kit.
7.3 Fuel Pressure Test
8c. Electric Fuel Pump
a. Measure Fuel at Fuel Bowl Test Port Spec . 45 psig WOT >42 psig
b. Measure at fuel outlet from electric fuel pump should be 51 ± 4.5 PSI @ idle.
c. Road Test- engine at full load condition 42 PSIG MINIMUM*
d. If fuel pressure fails low, go to step 8d.
e. If pressure is above min. spec, replace right check valve.
8d. Electric Fuel Pump Inlet Restriction.
a. If fuel line is restricted above 6 Hg, check for: blockage between pump and fuel tank.
b. If fuel line is not restricted, inspect regulator valve condition and for debris, If OK replace pump
Lead Driver
Joined: Apr 2011
Posts: 8,259
Likes: 346
From: Northern California
My guess is you have not driven without your tunes long enough for your comprehensive monitor to complete its cycle.
if you do not have Forscan or another way to check ford’s specific DTC or run PIDs and you are fairly certain your engine is all stock and in good order you could just get one of these and drive around until the little green light comes one to let you know it is ready.
be sure to do at least 3 WOT pulls up a incline to 65 mph...like getting on a freeway on ramp, this is the 35 to 65 mph part that checks MFDES outlined in 3c I posted above.
scroll down the page
IMready
if you do not have Forscan or another way to check ford’s specific DTC or run PIDs and you are fairly certain your engine is all stock and in good order you could just get one of these and drive around until the little green light comes one to let you know it is ready.
be sure to do at least 3 WOT pulls up a incline to 65 mph...like getting on a freeway on ramp, this is the 35 to 65 mph part that checks MFDES outlined in 3c I posted above.
scroll down the page
IMready
Fleet Mechanic
Joined: Jul 2010
Posts: 1,753
Likes: 34
From: Los Angeles, Ca.
My 7.3 smog drive cycle. Remove tune, clear computer, drive approximately 1.5 miles to McDonalds to get food for the assumed long drive cycle ahead of me, scan vehicle while waiting in drive through, discover that the monitors are already set, go to smog shop, pass, reinstall tune while chit chatting with tech, go to AAA for reg.
Bone stock '02 Ex, I was using a borrowed Super Chips 1705 at the time. It might pass with the tune but I had fault codes from experimenting with sensors and needed to clear them anyway so I pulled the tune to be on the safe side.
Bone stock '02 Ex, I was using a borrowed Super Chips 1705 at the time. It might pass with the tune but I had fault codes from experimenting with sensors and needed to clear them anyway so I pulled the tune to be on the safe side.