ECU Replacement Nightmare!

[SonnyF]

Help Guys! My beloved 2007 9-3 started to misfire badly, so took her to mechanic and after a through check (Error code P02450 his conclusion was ECU failure. I proceeded to search for a pre-own ECU replacement but the local garage guy said after replacing the ECU need to reprogram with Tech 2. Which I also located a guy to do it, BUT here is the fun part. The tech guy said because the central lock system is linked to the ECU as well and after reprogramming the ECU the central locking system will not work??? So Im in a desperate situation where I have absolutely no idea what to do next! If anyone share the same experience please HELP!

[swisssaabist]

Must confirm my allegations but thinking your Twice module must be reprogrammed with Tech II, others here can infirm or confirm what I say

[SonnyF]

Thanks ! So you are saying I need to reprogram both Engine ECU and also reprogram Central Lock ECU?

[swisssaabist]

the twice (theft and central locking) is dependent of the ECU datas like VIN number and others things. the twice is under the driver seat. but must be confirmed by others people here some are most qualified that i' am. your ECU must first be updated with the correct software version then with data from your car.
but seems strange the misfires is related with a bad ECU That kind of modules are generally strong,
Do you have been going to a Saab dealer ? is he used a Tech II ?

[Digger]

Help Guys! My beloved 2007 9-3 started to misfire badly, so took her to mechanic and after a through check (Error code P02450 his conclusion was ECU failure. I proceeded to search for a pre-own ECU replacement but the local garage guy said after replacing the ECU need to reprogram with Tech 2. Which I also located a guy to do it, BUT here is the fun part. The tech guy said because the central lock system is linked to the ECU as well and after reprogramming the ECU the central locking system will not work??? So Im in a desperate situation where I have absolutely no idea what to do next! If anyone share the same experience please HELP!

Could you please describe this problem with a little bit more detail. Would be helpful to know which motor is in the car, was the old controller divorced before installing the replacement and if replacing the controller fixed the misfire problem.

[SonnyF]

No did not dare going to Saab dealer cause their cost will most likely be higher than what my car is worth now!

[SonnyF]

Thanks Digger. Mechanic took apart everything clean out all the coils spark plugs etc and confirm there are no sparks on 2 of the cylinder and OBD comes back with error code P0245. And seems this is a common problem with 9-3 !

[Digger]

Thanks Digger. Mechanic took apart everything clean out all the coils spark plugs etc and confirm there are no sparks on 2 of the cylinder and OBD comes back with error code P0245. And seems this is a common problem with 9-3 !

P0245 is an emissions code and if this happened after pulling plugs and coils it's probably a bad wire connection. If not and you have the 2.0, look to the boost pressure valve first. The WIS doesn't say this, but I say if you have the 2.8 / GM V6, look to the egr valve first.

[swisssaabist]

Understand a non Saab couldn't tell precisely if the ECU is bad regarding to one code of misfire you must check other potential culprits before spending money for ECU

[Digger]

Understand a non Saab couldn't tell precisely if the ECU is bad regarding to one code of misfire you must check other potential culprits before spending money for ECU

Like Swiss says, check the most likely culprits before replacing the ECU. A shorted boost pressure / waste gate / solenoid will detune your engine and put you in limp home mode and trying to fix a misfire while you're in limp mode could take you down a lot of strange paths. A shorted wire, or boost pressure / waste gate / solenoid can also burn out the ECU and this has to be checked and fixed before replacing, or you will be replacing it again real soon. No Tech 2 programing necessary to fix a wire or replace a solenoid.

Not Tech 2 programming, but anytime you disconnect the battery, central locking needs to be re-synched to the remote fobs and to make sure you can use it when you need it, all the fobs need to be run through the ignition switch and cycled.

Like they say, old habits are hard to break and I have long standing first check for the not so venerable 60 degree V6. If you have the 2.8 V6 check the egr, the book doesn't include this with the code, but I know that when it's not bad enough to pop its own code it can cause others.

If you don't find a bad wire, connection, or solenoid, you will need Saab software with security access and for most people that means having a Tech 2 hooked to a PC running TIS. Sometimes it cost more to pay for this kind of help, sometimes it saves you money. Either way keep shopping for that good used engine controller. Kind of like buying a fire extinguisher, you don't really want to use it, but real nice to have handy when you need it.