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Snowgodccr
04-11-2011, 09:18 AM
So. My car has been sitting at my tuner for over a week now trying to get this problem sorted.

Car: 2002 WRX Sedan

Current mods that could affect the engine:
Grimmspeed Up Pipe
ACT Streetlite flywheel
Tomei Expreme Ti catback (installed after trouble started though)
AEM CAI (came on car)
Blitz BOV (came on car)

Problem: ECU cannot be flashed

Symptoms:

The car starts and runs just fine, about 95% of the time. Sometimes it will stall when coming to a stop and not want to restart. If I let it sit for a few minutes, it restarts and drives normally. Last time, I didn't have time to sit so I did a roll start down a hill and it hasn't done it to me again since (about 300 miles ago)

CEL is on, Catalytic converter performance out of spec or something like that

CEL cannot be cleared

ECU cannot be flashed

The shop has checked all the wiring between the OBDII port and the ECU and they found one wire that was "off". They fixed that, and the ECU still won't flash or communicate with his computer. They've been tuning other cars in between working on mine, so it's not their computer or cables.

I brought the car in for the fuel line recall at a dealership in early March. They did the recall and the car wouldn't start back up. They replaced the ECU and magically the car started. I brought the car (with a new ECU) back to my tuner shop to clear a CEL that came on because of the lack of EGT on the new up pipe. They couldn't clear the CEL now. Brought the car back to the dealership, they somehow cleared the CEL, it stayed off for a week and has since come back on.

I talked to the shop this morning, and now we're to the point where they can get into OBDII on the car, they can even Datalog the car, he just can't flash the damn maps.

The last trick they have up their sleeve to get this sorted out is to jump the pins right at the ECU and see if that works.

I NEED to get this ECU flashed because I have parts sitting at the shop waiting to go on. They can't go on until the ECU can be flashed though since they require a tune.

Anybody have any thoughts they'd like to throw in here? Anyone with a similar problem in the past?
$1600 for a Hyrda is not in the cards at this time.

KevinWelker
04-11-2011, 10:54 AM
I've heard of them just locking up and refusing to take a flash. Get a spare ECU, they should be in the $100-150 range.

Snowgodccr
04-11-2011, 10:56 AM
I've heard of them just locking up and refusing to take a flash. Get a spare ECU, they should be in the $100-150 range.

This one is brand new...supposedly. With the BS that the dealership put me through, I'd only be half surprised to learn that they took my $250 and didn't give me a new ECU, especially since my passenger side floor mat was in the same position it was in when I dropped the car off.

KevinWelker
04-11-2011, 11:03 AM
The only other time I've seen an extreme amount of difficulty on multiple ECUs was when the engine wiring harness was hacked up by an owner. The final fix was to replace the engine wiring harness with one that was in good condition.
So, there could be some grounding issues or other problems that might have happened during the fuel line fix. Look carefully at the wiring harnesses on the intake manifold and back by the turbo where the ECU harness plugs into the engine harness.

Hope you can get this sorted out, electrical gremlins are tricky.

punkrockerjohn
04-11-2011, 11:08 AM
I'm Thinking bad ground somewhere, but I'm sure the shop checked that. Interesting...

Snowgodccr
04-11-2011, 03:08 PM
We're going to Jerry rig it for the time being - he's got another guy with a bugeye coming by this afternoon. I told him to put the parts on my car, put my ECU into the other bugeye, give me a canned Stage 2 map and put my ECU back into my car. I don't care about max power right meow, I just want to drive my car. I'll get the power when I have the money for a Hydra.

I'll hunt down the wiring gremlin on my own time in my own driveway...they're busy enough over there already.

Snowgodccr
04-13-2011, 01:35 PM
Are there any fuses that could cause a problem like this?

ZED E85
04-13-2011, 01:53 PM
I had a friend with an 02 that was really finnicky about being flashed....if I remember right we had to start the flash, wait for it to try and connect, and then turn the key to on. This was with a tactrix cable, not sure what you are using.

Sent from my DROID2

Snowgodccr
04-13-2011, 03:40 PM
We tried swapping my ECU into another bugeye today, it wouldn't flash in there either, and that was an '03.
I'm picking up a new (used) ECU tomorrow morning and it'll be going in sometime tomorrow. If it works, the rest of my parts will go in and I can go to my first RallyX on saturday, and my first AutoX on sunday!

I had a friend with an 02 that was really finnicky about being flashed....if I remember right we had to start the flash, wait for it to try and connect, and then turn the key to on. This was with a tactrix cable, not sure what you are using.

Sent from my DROID2

The sticker here is that the ECU can't be read either. It can't be read or written.

Snowgodccr
04-14-2011, 12:57 PM
I had a friend with an 02 that was really finnicky about being flashed....if I remember right we had to start the flash, wait for it to try and connect, and then turn the key to on. This was with a tactrix cable, not sure what you are using.

Sent from my DROID2

IT WORKED! :bow::bow::bow::bow::bow::bow::bow::bow:

Myself and my ancestors thank you 1000 times with the graces of many camels.

Snowgodccr
04-14-2011, 01:10 PM
My theory on this:

'02s of a certain build period may have some amount of extra resistance in the wiring somewhere. This extra resistance causes a lower voltage at the OBDII port, making it such that the voltage is too low for the Tactrix cable to be able to recognize as a functioning ECU. Upon turning the key to the "on" position, you get a voltage spike through the system of great enough magnitude that the cable can see the ECU and start talking to it. Basically, the running voltage at the OBDII port is too low for the Tactrix cable to recognize. I like this theory because at one point my tuner forgot to plug the cable into the OBDII port, and we got the same error message that time as the times that it WAS plugged in.

My father's theory:
The ECU is dumb and impatient. When you turn the key to the "on" position, the ECU may "ping" the OBDII port, and if nothing starts talking to it right away, it ignores any further OBDII inputs for reading/writing. Also a good theory.

It could also be a confluence of both, or nothing to do with either. We're both geeks.