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Engine swap causing ECU problems

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Mdozier7180

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Discussion starter · #1 ·
Hey! Long story short, bought a 2005 ford focus to do a engine swap that ended up having California emissions. Swapped engine, removed extra emissions. Traced wiring harness with new engine, everything seemed to still match up. ECU is now angry.The car will start and run, but the old exhaust manifold and cat had a third O2 sensor and its throwing all kinds of codes cause its now missing. I bought a ECU from a junkyard that would match with the new Engine, but when its plugged in the car won't start.

So my question is, is it just a matter of reprogramming the new ECU to my keys because of some Anti theft system, or is there more I need to do? Or, can I somehow use my old ECU and make the car run happy? (it pulls codes, and runs in open loop)

Sorry if this seems ignorant, but I've never had to downgrade emissions or known anything about California equipment. (and I know its probably a nono to do this)
 
#2 ·
did you swap out a PZEV duratec to a normal non PZEV Duratec?... if you did, you need to replace the ECU to match..

as for the car not starting yes you need to program the new ECU to the original keys..
 
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#4 ·
uumm give me a few ill see what i can find for you..
 
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#5 ·
Just for the silly question (I can't be sure WHAT you did) - why change from PZEV to non-PZEV?

The engine itself is no different between the two.

Only swapping the injectors to keep the better PZEV ones is really a direct engine item, no need to swap other parts to match the new engine instead of the old. Leaving old exh. in only requires the correct gasket, and exh. would be off/need one anyways.
 
Discussion starter · #6 ·
Well I bought a used engine from a mechanic that had all the accessories/wiring harness/exhaust manifold. So I just left the extra emissions equipment off when I did the swap. Since the new engine had its original exhaust manifold I just used it. Only thing I've swapped so far is just the ECU. (which I can't use until I program my keys) And I don't even know if the pinouts of the PZEV ECU are the same as the non.
Reasons for removing emissions equipment was because I have a mechanic friend who believes non PZEV has a slight performance gain and also easier to troubleshoot.
 
#7 ·
Wish I could help more, they talked you into a PITA that would have been a LOT easier if you just left it PZEV style.

Existing exhaust, existing accessories for PZEV (not much, just the air pump hdwe), and the Better PZEV injectors.

Right now you've got to cross fingers the new PCM works without codes, just not connecting to the missing pieces.
 
#9 ·
$100 thats a canned cost they charge a flat rate for it.
 
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#10 · (Edited)
Most dealers charge 1 hour at whatever their labor rate is. There's a dealer here that charges $145 to program keys for a gas engine vehicle and $185 to program keys for a diesel engine vehicle.

I love owner programming mode.... I've told several customers how to program keys on their own. Of course, owner programming mode won't help here....but if it's not already explained somewhere on the forum.... (I'm too lazy to search for it)


Edit: I can't get the connector pin-outs to load and even if they would, they'd be SVG file format.
 
#11 ·
would love to see how a normal consumer can wipe masters and reprogram 2 new masters..

feel free to send the file my way xD
 
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#13 ·
no, cars come stock with 2 keys. loose 1 key you cannot add another key you need 2 masters belonging to the car to program secondaries IE key 3 to 8. ive tried cheating a key into my old focus with only 1 master and ended up setting the car into protection and setting off its alarm.
i can go test that theory out but that will have to wait till the morning im not setting the cars alarm off trying to program a third non programmed key using only 1 master... i also personally dont want to add the third key because its one of the worn ones that the old style ignition cylinder ate and shaved it undersized badly and dont need to damage the new cylinder using an undercut key on it

only other way to program 2 new masters into an ECU is with a Key programmer, hiring a mobile auto locksmith, taking it to ford or using a tuner to defeat pats. all my work cars have 3 keys 2 masters which are locked in the safe at work and 1 secondary which the drivers get so if they loose it i can just cut a new ebay pats key and simply reprogram the car using the 2 factory masters that came with the car
 
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#14 ·
In the US, only fleet cars have "master" keys....unless the car has the feature that allows you to set a maximum speed, maximum radio volume, etc (can't remember wtf the feature is called).... In that case, it's the first 2 keys programmed to the vehicle.

Owner programming, at least on older vehicles in the US, only allows you to add 2 new keys. Beyond 4 keys, it starts erasing keys.

If you have 2 keys already programmed, you simply cycle each of those 2 keys to the run position, then back to off. Then insert up to 2 "non-programmed" keys and attempt to start the vehicle with each. If it starts, they programmed, if not, they didn't.

Some dealers will disable Owner Programming on vehicles that support it though... That way customers have to pay to get new keys programmed, or to have the feature turned back on. New vehicles that support it, come from the factory with owner programming enabled by default
 
#15 ·
sykozis said:
In the US, only fleet cars have "master" keys....unless the car has the feature that allows you to set a maximum speed, maximum radio volume, etc (can't remember wtf the feature is called).... In that case, it's the first 2 keys programmed to the vehicle.

Owner programming, at least on older vehicles in the US, only allows you to add 2 new keys. Beyond 4 keys, it starts erasing keys.

If you have 2 keys already programmed, you simply cycle each of those 2 keys to the run position, then back to off. Then insert up to 2 "non-programmed" keys and attempt to start the vehicle with each. If it starts, they programmed, if not, they didn't.

Some dealers will disable Owner Programming on vehicles that support it though... That way customers have to pay to get new keys programmed, or to have the feature turned back on. New vehicles that support it, come from the factory with owner programming enabled by default
Click to expand...

i dont drive nor have anything newer then a 2006.. terms for master keys are the 2 factory originals.. none of the cars i have have the options for max speed..

i guess i can call that mode granny mode or parental lockout LOL

the parental mode would be very quickly stripped from any of the cars i ever own in the future..
 
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#18 ·
Mdozier7180 said:
Hey! Long story short, bought a 2005 ford focus to do a engine swap that ended up having California emissions. Swapped engine, removed extra emissions. Traced wiring harness with new engine, everything seemed to still match up. ECU is now angry.The car will start and run, but the old exhaust manifold and cat had a third O2 sensor and its throwing all kinds of codes cause its now missing. I bought a ECU from a junkyard that would match with the new Engine, but when its plugged in the car won't start.

So my question is, is it just a matter of reprogramming the new ECU to my keys because of some Anti theft system, or is there more I need to do? Or, can I somehow use my old ECU and make the car run happy? (it pulls codes, and runs in open loop)

Sorry if this seems ignorant, but I've never had to downgrade emissions or known anything about California equipment. (and I know its probably a nono to do this)
Click to expand...
I realize this post was forever ago, but the reason your car won’t start after swapping the Ecu is you need to change out the key tumbler
 
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