PCM Update has changed how car drives

[Jay4424]

Hey guys, does anyone know if a pcm update is a straight forward process or does a technician have to input certain information into their laptop which they can easily screw up and thereby affect the car?

Basically my 2018 GT required a pcm update due to the change engine oil light coming on sooner than normal and according the the ford service manager it needed updating. it’s under warranty so didn’t cost me anything.

However, when I started the car up it rough idled during that first start up after I collected it and there was a bit of hesitation from the engine. It hasn’t done it since but my main concern was that it feels as though the torque/horsepower may have been affected since the car feels sluggish. Now rather than let ford have another try I thought I’d see if anyone with knowledge of these things can help.

Also if I were to get a tune done the line would this override whatever the update did or would I have to get a correct pcm update if required then get the tune?

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[ice445]

Any time the KAM (PCM memory) is cleared, like with an update, the car has to re-learn all the relevant parameters for engine performance and will likely be down on power for a little bit as a result. Maybe 100-200 miles or so. The main thing is that the computer wants to learn what octane value is being run so it can adjust timing accordingly. Until it knows that, it will use a base map with pretty low timing advance.

 

[fmc_smt]

And if you have an automatic the adaptive shift tables are reset . So the transmission will have to relearn also.

 

[ORRadtech]

Any time the KAM (PCM memory) is cleared, like with an update, the car has to re-learn all the relevant parameters for engine performance and will likely be down on power for a little bit as a result. Maybe 100-200 miles or so. The main thing is that the computer wants to learn what octane value is being run so it can adjust timing accordingly. Until it knows that, it will use a base map with pretty low timing advance.

And if you have an automatic the adaptive shift tables are reset . So the transmission will have to relearn also.

I understand that modern cars learn as they are driven.
My question is, why don't we hear complaints about new cars with minimal miles with rough start ups and/or poor/sluggish driving patterns?

 

[fmc_smt]

They go threw a drive cycle before the leave the plant , that is a base line to start with . If the tech doing the reprogram does a drive cycle about the only thing that you will notice is shifting and maybe fuel mileage.

 

[ORRadtech]

So what does a drive cycle consist of?
I've seen where people pick up cars with just 3 or 4 miles on them, does that constitute a drive cycle?
The OP said his was rough on the "1st" start but surely it had to be started and driven out of the repair bay so that couldn't really be the 1st start. And if the OP drove it home wouldn't that be a drive cycle? Although he didn't say how many times he has driven it since the reflash. Also, since it needs a drive cycle wouldn't that be part of the procedure for a reflash?
Not trying to hijack the thread, just trying to understand. And hopefully my questions will help the OP as well.

 

[Jay4424]

Cheers for the input guys. I’ve driven it about 50 miles on and off since but although the car starts up fine now, the drivability seems sluggish. It doesn’t feel as quick as it used to and funnily enough the mpg seems to have gone down even thought my driving habits haven’t changed.
I’ve got a manual performance pack and the drive modes work and you notice the change with each one but I just need to really push down a bit more on the throttle to get that quickness I’m used to.
It may just sort itself out over the short term as mentioned above but my main concern was whether the torque/horsepower could be affected by a technician who haphazardly inputs the wrong info when doing the update. My dash cam was on and I saw snippets of the technician with his laptop. He only drove it to the customer parking bay so I guess I was the next person to start the car up

 

[fmc_smt]

Hope this helps

On Board Diagnostic (OBD) Drive Cycle Description of On Board Diagnostic (OBD) Drive Cycle The following procedure is designed to execute and complete the OBD monitors. To complete a specific monitor for repair verification, follow steps 1 through 4, then continue with the step described by the appropriate monitor found under the OBD Monitor Exercised column. Federal OBD requires that all vehicles comply with 0.508 mm (0.020 inch) evaporative emissions (EVAP) system requirements in addition to meeting the 1.016 mm (0.040 inch) EVAP system monitoring requirements. The F-150 3.5L GTDI will use the engine off 0.508 mm (0.020 inch) EVAP monitor rather than the 1.016 mm (0.040 inch) EVAP monitor to set I/M Readiness. For the EVAP system monitor to run, the ambient air temperature must be between 4.4 to 37.8°C (40 to 100°F), and the altitude below 2,438 meters (8,000 feet). If the OBD monitors must be completed in these conditions, the PCM must detect them once (twice on some applications) before the EVAP system monitor can be bypassed and OBD monitors readied. The EVAP Monitor Bypass procedure is described in the following drive cycle. Use a scan tool to carry out the OBD drive cycle. Refer to the scan tool manufacturer's instruction manual for each described function. A detailed description for clearing the continuous diagnostic trouble codes (DTCs) is found in this section. Refer to Drive Cycle Recommendations WARNING Strict observance of posted speed limits and attention to driving conditions are mandatory when proceeding through the following drive cycles. Failure to follow these instructions may result in personal injury. 1. Most OBD monitors complete more readily using a steady foot driving style during cruise or acceleration modes. Operating the throttle in a smooth fashion minimizes the time required for monitor completion. 2. The fuel tank level should be between 1/2 and 3/4 full with 3/4 full being the most desirable. 3. The EVAP purge flow monitor can operate only during the first 30 minutes of engine operation. When executing the procedure for this monitor, stay in part throttle mode and drive in a smooth fashion to minimize fuel slosh. 4. The EVAP 0.508 mm (0.020 inch) leak check monitor runs after the ignition is turned OFF. The vehicle must be driven to complete the EVAP purge flow monitor to increase the temperature of the fuel in the fuel tank. 5. When bypassing the EVAP engine soak times, the PCM must remain powered (ignition ON) after clearing the continuous DTCs and relearning emission diagnostic information. For best results, follow each of the following steps as accurately as possible: OBD Monitor Exercised Drive Cycle Procedure Purpose of Drive Cycle Procedure Drive Cycle Preparation Note To bypass the EVAP soak timer (normally 6 hours), the PCM must remain powered after clearing the continuous DTCs and resetting the emission monitors information in the PCM. 1. Install the scan tool. Turn the ignition ON with the engine OFF. Cycle the ignition OFF, then ON. If needed, select the appropriate vehicle and engine qualifier. Clear the continuous DTCs and reset the emission monitors information in the PCM. Bypasses the engine soak timer. Resets the OBD monitor status. 2. Begin to monitor the following PIDs (if available): AAT, ECT, EVAPDC, FLI, IAT and TP MODE. Start the vehicle without returning the ignition to the OFF position. 3. Idle the vehicle for 15 seconds. Drive at 77 to 104 km/h (48 to 65 mph) until the engine coolant temperature is at least 76.7°C (170°F). Prep for Monitor Entry 4. Is the ambient air temperature between 4.4 and 37.8°C (40 and 100°F)? If AAT is not available, IAT is used. If not, complete the following steps, but note that step 16 is required to bypass the EVAP monitor and complete the OBD drive cycle. Engine warm-up and provides ambient air temperature input to the PCM. If AAT is not available, IAT is used. HO2S 5. Cruise at 77 to 104 km/h (48 to 65 mph) for greater than 5 minutes. Executes the HO2S monitor. EVAP 6. Cruise at 77 to 104 km/h (48 to 65 mph) for 10 minutes (avoid sharp turns and hills). NOTE: To initiate the monitor, the throttle should be at part throttle, EVAPDC must be greater than 75%, and FLI must be between 15 and 85%, and for fuel tanks over 25 gallons FLI must be between 30 and 85%. Executes the EVAP purge flow monitor if the ambient air temperature is between 4.4 to 37.8°C (40 to 100°F). Catalyst 7. Drive in stop and go traffic conditions. Decelerate at closed throttle and then moderately accelerate from each stop. Include 5 different constant cruise speeds, ranging from 40 to 72 km/h (25 to 45 mph) over a 10 minute period. Executes the catalyst monitor. EGR 8. From a stop, idle for 30 seconds, accelerate to 72 km/h (45 mph) at 1/2 to 3/4 throttle, cruise at steady throttle for 1 minute. Repeat idle, acceleration and cruise 3 times. Executes the exhaust gas recirculation (EGR) monitor. CCM (Engine) 9. Bring the vehicle to a stop. Idle with the transmission in drive (neutral for M/T) for 2 minutes. Executes the idle air control portion of the comprehensive component monitor (CCM). CCM (Transmission) 10. For M/T, accelerate from 0 to 80 km/h (0 to 50 mph), and continue to step 11. For A/T, from a stop and in overdrive, moderately accelerate to 80 km/h (50 mph) and cruise for greater than 15 seconds. Stop the vehicle and repeat without overdrive to 64 km/h (40 mph) cruising for greater than 30 seconds. While at 64 km/h (40 mph), activate the overdrive, accelerate to 80 km/h (50 mph) and cruise for greater than 15 seconds. Stop for at least 20 seconds and repeat step 10 five times. Executes the transmission portion of the CCM. Misfire, Fuel And Deceleration Fuel Shut Off Rear HO2S Monitors 11. From a stop, accelerate to 104 km/h (65 mph), hold steady throttle for 5 seconds, then decelerate at closed throttle to 64 km/h (40 mph) (no brakes), accelerate from 64 km/h (40 mph) to 104 km/h (65 mph), hold steady throttle for 5 seconds, repeat deceleration 5 times. Allows learning for the misfire monitor, and completion of the deceleration fuel shut off rear HO2S monitor. Readiness Check 12. Access the On Board System Readiness (OBD monitor status) function on the scan tool. Determine whether all non-continuous monitors except the evap monitor have completed. If not, go to step 15. Determines if any monitor has not completed. EVAP 13. Turn the ignition OFF for 1 hour to allow the engine off 0.508 mm (0.020 inch) leak check to run. Executes the 0.508 mm (0.020 inch) EVAP monitor. Readiness Check 14. Turn the ignition ON. Access the On-Board System Readiness (OBDII monitor status) function on the scan tool. Determine whether all non-continuous monitors including the evap monitor have completed. If not, go to step 15 Determine if any monitor has not completed. Pending Code Check And EVAP Monitor Bypass Check 15. With the scan tool, check for pending codes. Conduct the normal repair procedures for any pending code concern. Otherwise, repeat any incomplete monitor. If the EVAP monitor is not complete and the ambient air temperature was out of the 4.4 to 37.8°C (40 to 100°F) temperature range in step 4, or the altitude is over 2438 m (8000 ft.), the EVAP bypass procedure must be followed. Go to Step 16. Determines if a pending code is preventing the completion of the OBD drive cycle. EVAP Monitor Bypass 16. Park the vehicle for a minimum of 8 hours. Repeat steps 2 through 14. Do not repeat step 1. Allows the bypass counter to increment to 2.

 

[fmc_smt]

And for you automatic guys
Adaptive Learning Drive Cycle



Configuration

NOTE: Perform the adaptive learning drive cycle on a level road surface.

NOTE: The engine and transmission must be at normal operating temperature with the transmission fluid at the correct level.

1. Record then clear the DTCs (Diagnostic Trouble Codes).

1. Warm the engine and transmission to normal operating temperature.

1. With the selector lever in (D), moderately accelerate from stop to 80 km/h (50 mph) allowing the transmission to shift into 6th gear. Keep vehicle speed and throttle steady for a minimum of 15 seconds.

1. With the transmission in 6th gear and maintaining steady speed and throttle, lightly apply and release the brake to operate stop lamps. Maintain the speed and throttle for a minimum of 5 seconds.

1. Brake to a stop and remain stopped for a minimum of 20 seconds.

1. Repeat Steps 3 through 5 five times.

 

[Elp_jc]

My question is, why don't we hear complaints about new cars with minimal miles with rough start ups and/or poor/sluggish driving patterns?

The main thing a lot of folks don't do is to allow the engine to idle after it warms up. It needs that to learn the fuel trims again. It takes several minutes to adjust to an acceptable level, but about 20 minutes total to get to 100%. If you start driving right away, or almost right away, it'd take a lot longer.

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