edilberovic

I own a 97 auto and my car has been doing some strange things for a while now. A few of my car buddies have told me the 97s are knows for ECU problems and that could be the case here. Also tuning is a PITA so i am looking to upgrade to a z06 ecu or a good aftermarket ECU. Any suggestions? Or any places where i can find a z06 ecu?
THANKS

tblu92

Knowing all your mods will help in deciding if you need an ECM update
Assuming you just have a bolt on type car and no cam or heads or boost--tells me you will get NO benefit from a newer model ECM----The reason many update an older ECM is because if they are running the STOCK MAF open/closed loop system a 97 ECM MAF table ends at 11250 HZ-----This means it can only support approx. 450 RWHP--Updating to the later ECM's will give the MAF table a higher ceiling at 12500 HZ which can support 500+RWHP---So if you future plans don't include mods that will exceed 450 RWHP then your 97 ECM is fine-----
PLUS it takes a lot of work in transferring tables from a 97 ECM into a newer one--so a re-tune is deff. needed---There would be NO HP or drivability advantages for an update unless you exceed the HP potential of your ECM

edilberovic

Sorry for the late reply.
The car is a bolt on car with a LS6 manifold and i believe a 92mm tb not drive by wire.
The plan is to ProCharge it in a year or so. I was leaning more towards a aftermarket ECU if there is a option with a A4 and plug in play.
But I think all of my issues that I need to fix right now are BCM related the car does some strange things at makes me think what the F*$k.

tblu92

All C5's came with DBW---If you changed it to cable T-Body--then there are several tables in your tune that must be changed to accommodate the cable system--You must be certain that you are getting the TPS signal correctly as I believe the pigtails are different on both-Also---A DBW T-Body does not have an "idle air control valve" IAC but most cable throttles do---This also requires tuning as the IAC is used for start up and deceleration- If your issues include hard starts flooding--surging--dying--then this could be why---

RonSSNova

The C5 won't have the wiring for an IAC. In fact, the entire car will be very pissed off with a DBC throttle.....

97 PCM is also rather slow compared to the later 99 up units. Not that the engine really cares.

In the end though, the harness can be repinned for the later ECU but it's not trivial.

edilberovic

I think this might be the issue. I purchased the car with all of the parts on it. I did get a CEL and my wording might not be exactly right but it was something to do with the TPS singnals not communicating properly. I was in park then all the sudden the car started bogging so i turned it off waited a few min then turned it back on. When i turned it back on i got that CEL code. Its showing all of the issues you mentioned, I will make a appointment with a local tuner for him to look at it. If need be ill just go back to a DBW. Thanks for you help!!

tblu92

Did they re configure your throttle with a cable system ?? If so that was a huge error---basically If your car came with a DBW you need to install anther one
Just for your Information---A 102 T-Body is really an overkill for most applications anyway---The STOCK T-body can produce plenty of airflow for most all applications including boosted-----If you still have the stock T-Body I would re-install it and it should be fine
Typically a larger t-body is only needed when :
Having larger than stock cubic inches
Rubbing your car consistently over 6500 RPM's
Running beyond 8 PSI boost
IF your car does NOT fit any of these scenarios then install the STOCK T-Body
Otherwise you will need to trade your cable 102 for a DBW 102 which can be double the price and the net results may produce maybe even LESS HP and TQ especially below approx. 6000 RPM's----So not a reasonable mod----