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Discussion Starter · #1 ·
I'm considering doing the the fuse pull ECU reset trick on my 04 R. Is it a bad idea if there is nothing seemingly wrong with the car? Are there or has anyone experienced any adverse effects from it? Will it effect anything on my gauge cluster? Does the car take time to "get back to normal" or are the effects instant?
 

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Should be fine. R feels great afterwards.
 

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Details about said ecu reset?
 

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Discussion Starter · #4 ·
I'm considering the reset where you pull fuse 6 and 23, try to start the car and replace the fuses. But I'm not sure if I should because there really isn't anything noticeably wrong (CE light, etc). The performance of the car really hasn't changed since I bought it in June but I wanted to see if doing the ECU reset would improve it in anyway.
 

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I'm considering the reset where you pull fuse 6 and 23, try to start the car and replace the fuses. But I'm not sure if I should because there really isn't anything noticeably wrong (CE light, etc). The performance of the car really hasn't changed since I bought it in June but I wanted to see if doing the ECU reset would improve it in anyway.

It'll be crazy fast for a little while but gradually it will reign itself back in. If you have a tune, you have to be very careful, because you'll often see boost spikes well over 20psi. It's not really worth it except for a temporary boost, and could be risky if you have any mods.
 

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I have VIDA, had VADIS before that and also have use of Autologic.
The computer learns the oxygen sensor signals, MAF offset, and ETA operation, NOT you or your driving.
If someone disconnected your battery and did a test drive where it idled, ran at 2000 RPM and slower at light throttle and then ran it over 2000 rpm at steady light throttle and then you got in your car and drove it w/o knowing you'd see no difference UNLESS there was a repair. Before and after fuel trim values will go back where they were with no mixture impacting repairs.

I have cleared hundreds of Volvos as part of diagnostics and compared before and after. The only time it changes is when there is a part replacement or some repair that affects mixture.

Initially you may see it run better as the fuel trim adjustment may take it leaner than the default values in ECM prior to it completing fuel trim re-learn (adaptation).
You may also initially have it run worse is there are any contributing factors that would adjust that car to a richer adapted fuel trim as compared to default values.

DO you know how many times a customer tells me there runs so much better than before I worked on it when I did nothing that could have had any impact on the performance. Of course I also get comments that it runs worse when I've done no repairs that could have had an impact.

I get loads of positive comments when I do brake pad replacement or an oil change and as part of that I adjust door latches or lube binding door hinges or tighten the door check strap attachment to body to eliminate noises or issues that DRIVE ME BATTY!.
I often center steering wheels and get comments as to how much better the car drives when no other changes were made that coukld have made any difference.

We are humans and we love to confirm whatever suspicion or expectation we have. Period.

Millions of dollars worth of MPG improving gadgets have been sold where the purchaser at least initially RAVED about MPG gains.
Same with adding dual exhaust to vehicles.
If I do something that is supposed to improve MPG then I drive like MPG matters to assure I see if it makes a difference.
 

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I have VIDA, had VADIS before that and also have use of Autologic.
The computer learns the oxygen sensor signals, MAF offset, and ETA operation, NOT you or your driving.
If someone disconnected your battery and did a test drive where it idled, ran at 2000 RPM and slower at light throttle and then ran it over 2000 rpm at steady light throttle and then you got in your car and drove it w/o knowing you'd see no difference UNLESS there was a repair. Before and after fuel trim values will go back where they were with no mixture impacting repairs.

I have cleared hundreds of Volvos as part of diagnostics and compared before and after. The only time it changes is when there is a part replacement or some repair that affects mixture.

Initially you may see it run better as the fuel trim adjustment may take it leaner than the default values in ECM prior to it completing fuel trim re-learn (adaptation).
You may also initially have it run worse is there are any contributing factors that would adjust that car to a richer adapted fuel trim as compared to default values.

DO you know how many times a customer tells me there runs so much better than before I worked on it when I did nothing that could have had any impact on the performance. Of course I also get comments that it runs worse when I've done no repairs that could have had an impact.

I get loads of positive comments when I do brake pad replacement or an oil change and as part of that I adjust door latches or lube binding door hinges or tighten the door check strap attachment to body to eliminate noises or issues that DRIVE ME BATTY!.
I often center steering wheels and get comments as to how much better the car drives when no other changes were made that coukld have made any difference.

We are humans and we love to confirm whatever suspicion or expectation we have. Period.

Millions of dollars worth of MPG improving gadgets have been sold where the purchaser at least initially RAVED about MPG gains.
Same with adding dual exhaust to vehicles.
If I do something that is supposed to improve MPG then I drive like MPG matters to assure I see if it makes a difference.
I like the cut of your jib sir!
 

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I thought the transmission relearns if you do the fuse pull reset?
 

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The transmission's relearning is a simple thing also that has taken an internet life if its own.
The TCM monitors completion time for shifts. It starts off being too long after adapted value clearing and TCM increases the duty cycle to build pressure more rapidly and for some gear changes also decreases duty cycle more rapidly for brake or clutch being released for that shift until target time is achieved. There is an acceptable shift time range so the shift can be quicker up to a point and then the duty cycle rate of increase will be slowed until the time gets longer to be within the OK range. Towing trailers and using higher settings if you have a multiple tune programmer device can create the extra firm to harsh shifts that gets smoothed back to a nicer shift after driving once tune is reduced or trailer is unhooked.

The single "learns me" thing the trans can do is a mode that you might call "switchback mode". If you lift throttle and coast the standard actions of TCM will cause an upshift. IF you are driving aggressively on twisty road or driving a stair step ascending or descending mountain road then the TCM will see the repetitive lift and apply and will hold gear range when you lift. When things stabilize this mode is exited with no action on your part.
The transmission does not care who is behind the wheel.
 

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I need to do this too. My transmission adaptation mode is all wacked up right now too and is causing a CEL. lol
 

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Batt reset doesn't clear 6 speed auto TCM's. None of the TCM's that are mounted on trans for that matter (P1's 5 speed has the TCM on gearbox).
 

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The only person I've seen with problems was Sean. I remember we use to give him a hard time because he was resetting his ECU on a weekly basis... well maybe not weekly, but alot.

 
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