PCM updated for 2020 gt?

[Albertcado]

Hi all,

I recently had to take my car in to the dealership because the "wrench light" came on randomly while driving and it went into limp mode.
I parked the car and restarted the engine, the wrench light was gone and the car seemed to drive normally.
Either way I wasn't taking any chances so I took the car in and they ran the codes. Tech told me that the PCM was not 100% accepting certain codes or was not functioning properly which caused it to "think" something was wrong or off which set off the "wrench light" warning and limp mode.

He said there was actually an update for the PCM on my 2020 mustang gt and when it was updated, all codes came back error-free and that it had accepted the update with zero issues. The car seems to be driving fine and no dash warnings or issues since the update.

Is this PCM update something you guys have heard of or know if it has any negative effects to the engine, say limiting power output or related?

Sponsored

 

[Bikeman315]

Is this PCM update something you guys have heard of or know if it has any negative effects to the engine, say limiting power output or related?

Happens all the time. No different then operating system updates on your pc or mobile device. There should be no negative effects in having the update done. If there is you can expect another update.

 

[Albertcado]

Happens all the time. No different then operating system updates on your pc or mobile device. There should be no negative effects in having the update done. If there is you can expect another update.

Good to know, thanks for the helpful info. So far she's running great after the PCM update and no "wrench lights" or CEL.

 

[Schwerin]

Happens all the time. No different then operating system updates on your pc or mobile device. There should be no negative effects in having the update done. If there is you can expect another update.

Tell that to people that bought the Ford Racing ZX2 PCM from Ford for $500 or bought a 2000 ZX2 S/R. They would dyno 122WHP, then after an "emissions update" they went down to 100WHP. Which was 10-12WHP less than a normal 5spd non-FR PCM ZX2 and about the same as the automatic 4spd ZX2. It made the price of non-flashed PCM's jump on ebay and people would swap PCM's before taking it to Ford just to keep from it accidentally getting flashed.

Ford really FUCKED those people. Bought a car that was faster than the usual 5spd ZX2 and ended up with a car making the power of a slow As Shit model auto.

 

[Brokestang]

I know nothing about computers but it seems they must program them to mess things up so then you have to bring it for them to "update "it. How was it able to leave the dealers lot running & driving fine for thousands of miles & then it won't run without this "update".

 

[Schwerin]

I know nothing about computers but it seems they must program them to mess things up so then you have to bring it for them to "update "it. How was it able to leave the dealers lot running & driving fine for thousands of miles & then it won't run without this "update".

Likely if you just pulled your battery cable and let the power drain to kill the stored memory you'd have been back to being just fine. Sometimes memory leaks creep up.

I'm still not sure why not EVERY car has the exact same PCM code. They all have the same hardware, why does ford have multiple PCM codes with slightly different tweaks between them? Seems a waste of development time.

I remember back in the ZX2 Escort days you could track every PCM tune back to 2 original ones. because you could see that some codes all had the EXACT A/F maps of one code but then would have different Timing maps. Another branch would have the same A/F Of the OTHER PCM but then different timings.

Then 2 more branches had the same Timing Maps but then different A/F maps. It was so strange, and each branch would have numbered version like MTX0-MTX4, and some going up to 9, meaning there were 9 different version of code alone, and there was like 4+ branches each having multiple revisions. It was the DUMBEST thing I've ever seen from a tuning/coding POV.

The 2 initial codes were the Ford Racing tunes, and every other tune was a "gimped" version of them either gimped by timing or A/F. Then later when they did the Emissions update it was a flash that applied to ALL the PCM code that brought it back to just 1 very neutered tune. It was like the ZX2 was some kind of odd PCM/tuning testing ground for Ford who how knows why.

The whole thing still boggles my mind years later. As a developer myself I can't think of ANY reason it was all done. When the initial 2 tunes had the best power, best fuel economy, and passed 50 state emissions.

 

[Mdtaylorjr]

Hi all,

I recently had to take my car in to the dealership because the "wrench light" came on randomly while driving and it went into limp mode.
I parked the car and restarted the engine, the wrench light was gone and the car seemed to drive normally.
Either way I wasn't taking any chances so I took the car in and they ran the codes. Tech told me that the PCM was not 100% accepting certain codes or was not functioning properly which caused it to "think" something was wrong or off which set off the "wrench light" warning and limp mode.

He said there was actually an update for the PCM on my 2020 mustang gt and when it was updated, all codes came back error-free and that it had accepted the update with zero issues. The car seems to be driving fine and no dash warnings or issues since the update.

Is this PCM update something you guys have heard of or know if it has any negative effects to the engine, say limiting power output or related?

This is totally normal. You'd be surprised at how thorough ford actually tests the engine, Trans, and tunes. The one thing they cannot account for is the driver and different fuels across the country and when they start seeing repeated issues they look into it and issue a tsb to the dealers and a code update. To answer another question no they do not program them to fail because they still have to pay the dealer for warranty time for the updates. But a pcm update to solve what could cause a major problem down the road they will pay it.

Sponsored