Jump to content
Sign in to follow this  
theRuler

vr6 ecu reset - how?

Recommended Posts

Either pull the ECU wiring harness out or disconnect the battery. Around 10 mins should do it, then reconnect. All 'learned' parameters and error codes will then be deleted.

Share this post


Link to post
Share on other sites

Just out of interest , why do you need to reset the ecu and will there be any down side's ?? :|

Share this post


Link to post
Share on other sites

its done 148,000 miles now, and it doesn't run as crisp as it used to.

 

some dude at work said he resets the ecu in his pug (every now and again) and that makes it run nice

 

the car still drives nice. although the gearbox is getting "loose"

Share this post


Link to post
Share on other sites

Sometimes resetting the ECU helps if the fuel trimming has gone out of range or if the knock sensors have been activated frequently. It just forces the ECU to reset everything and start over. Kind of like rebooting a Server that's getting laggy.

 

There are no downsides. Just make a note of the errors, if any, with VAG-COM before resetting it, but they'll come back anyway if there are persistent problems.

Share this post


Link to post
Share on other sites

I reset my ECU all the time (a side effect of all the work I've been doing on it recently :roll: ) It does seem to drive a lot crisper afterwards, but really needs a good 'mixture' of driving immediately after a reset so the ECU can adapt to the full range of driving conditions.

 

Cheers,

Robbo

Share this post


Link to post
Share on other sites

I wonder if it's worth hooking up a switch to the ECU's earth or power supply so that you can reset it without the hassle of lifting the bonnet and hoiking the battery lead off?

 

That way, you can nip to the shops, cut the ECU power, get back in the car, flip it back on and assess the changes (if any) on the way home?

 

Subarus have an 'in car' reset function by touching a green wire to a black one I think, which also then puts it in diag mode...... so no reason why us VR drivers can't enjoy the same convenience :lol:

Share this post


Link to post
Share on other sites
Guest

sounds like a good idea Kev, I'm surprised you don't have one already ;)

Share this post


Link to post
Share on other sites

Is all this stuff about mid-throttle accel in 4th from 25mph and full throttle in 3rd from 3,500 rpm really necessary?

 

I was thinking of doing a reset on my car but am scratching my head to think of a suitable road for the 3rd gear acceleration procedure which won't put my license under threat!

Share this post


Link to post
Share on other sites

The car will readapt ignition timing every time you start the ignition. The only long-term learned figures are for fuelling mostly, iirc.

The ECU reset does not *fix* anything. If you have an array of sensors on the engine that all work, there is really no need to reset the ECU. Indeed the factory manuals all state that when replacing an ECU you should record the adaptation values in the old ones and reinstate them using VAG-COM or equivalent afterwards.

 

It's one of those "voodoo" fixes that everyone thinks does magical things and it plain doesn't.

 

The only possible benefits for performing the reset as described above (the full throttle for 3 seconds, part throttle in 4th etc etc) is to force the engine to adapt to either a new sensor or a new air flow characteristic more quickly, or to remove saved error codes more quickly. (I am led to believe that for example if you have a duff lambda, fitting a new one will require three engine start cycles and power-on-self-test passes before the new part gets fully trusted.)

 

I know the microsoft world always tells you a reboot fixes everything (and bloody mobile phones are getting the same way now!!), but the VR6 car ECU is not that clever!

 

My 2p. :-P

Share this post


Link to post
Share on other sites

Not really. After reconnecting the battery, just let it idle for a few minutes, then take it for a drive and do at least 1 or 2 full bore blasts in 3rd. The rest it will learn as you go along. You don't have to max the revs in 3rd, the ECU is just 'learning' your throttle movements, so just floor it in 3rd and hold it there for a few seconds.

 

Vince at Stealth says the relearning procedure doesn't really do much but resetting the ECU has other uses though, such as resetting all the MAF and TPS, ISV calibration etc.

 

K

Share this post


Link to post
Share on other sites

Thanks Matt,

 

The reason I asked was I ran the battery flat by leaving the interior light on for about 2 days without noticing and hand to jump start the car this morning. Just wondered if a very low battery would keep the ECU values or whether a reset was the answer.

 

The other thing is that the pinking has returned (after a long absence) between 3 and 4,000rpm. I suspect a bad tank of BP Ultimate as it came back quite suddenly - just to play mind games with me :roll:

 

I know the microsoft world always tells you a reboot fixes everything (and bloody mobile phones are getting the same way now!!), but the VR6 car ECU is not that clever!

 

I wouldn't say that M$'s constant need to reboot was a "clever" feature of the OS! Haven't touched windows for a long time anyway, thankfully.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...