SwedeSpeed - Volvo Performance Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
199 Posts
Discussion Starter · #1 ·
I've only put 12K kms on ours since picking it up with 60K on it. Its been a 9 out of 10 with just a couple small 'bugs' since picking it up. One was an off the gas coasting issue that bugged me. When off the gas and coasting/braking for say a 90degree corner, it would drop to idle rpm and you would roll around the corner without any engine braking. The transition to accelerating again wasn't exactly smooth, but pretty well how a north american car does it to.<br>I drove around this problem ok, but also I was noticing a lazy downshift from cruising speed. At 80-100kph its only turning 1600-1800 rpm and when stepping down slightly on the gas the rpm would burp upward slightly for a moment, but not downshift. Kind of like it wanted to downshift but changed its mind. More gas and it would go down 2 gears instead of one. I was a little concerned about this since I've towed a lot since getting the vehicle.<br>So, off to the dealer (under warranty). I got a very knowledgable shop foreman who came out for a test drive with me as a passenger. I asked them to check it out and at least change the trans oil, even though its supposed to be a lifetime oil, I've done it in a few other Volvo's and got 300-400k kms out of them so I still think its a good idea. <br>The tech said he had never had a V8 engine/trans warranty issue before which I was a little concerned about, knowing this could turn into a waste of time and end up being a 'works as designed' comment from them. But he did say the transition from neutral to drive/reverse was a bit abrupt and would look into it, and could even be a transmission mount. Good, at least he acknowledged it wasn't quite right. <br>The tech checked the mounts (fine), no codes, but there was tech bulletins and software updates for both engine and trans available that pretty well fit the description of my concerns. So they went ahead with the updates (free), changed the oil (wasn't too bad looking, meaning it was showing some signs that a change wouldn't be a bad thing... under $300) and after he found out I had bought it used from a city driver, he offered to put it into adaptive mode so it would re-learn my driving habits which is 90% rural)<br>I'm very happy now. Smoother shifting than ever, it holds the lower gears slightly longer and provides much better engine braking at slow speeds without any jerky off the gas/on the gas transition. Gearing down 1 gear from cruising speed is also much easier now.
 

·
Registered
Joined
·
199 Posts
Discussion Starter · #3 ·
Re: (crash)

You positive about that? I kinda doubt it since things like seat/mirror positions, radio stations, and clock all stayed the same. Unless they use a RAM memory in everything except the TCU that is. I don't think unhooking the battery resets any stored engine codes either.
 

·
Registered
Joined
·
498 Posts
Re: (cdnx90)

I think the tranny software update wipes out all adaptive related data stored in the system.
 

·
Registered
Joined
·
270 Posts
positive. during an intermittent tranny problem, we discussed the issue with a volvo service rep. disconnecting the battery purges the 'cache'. there's most like a way to do it from the OBD connection as well.<p>as exlpained to me, the adaptive shift never stops. the more shift patterns that are recorded means that the adaptive shift logic can try to anticipate the next one.<p>similarly, the engine computer also does a diagnostic test everytime the ignition key is turned on and reports faults codes if present and not necessarily causes a permanent fault code.<p>I believe there is also some sort of 'error log' that's available. I remember the service rep talking about reviewing 'recent' fault codes for a diagnostic fee of $89.<p>I also noticed that there is a reset cycle on 'programmed' settings such as seats and mirrors. I'm thinking it's annually. In the 5 years ownership, I noticed it to be a scheduled event(I just don't know how often <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/tongue.gif" BORDER="0"> )<p><br>
 

·
Registered
Joined
·
26 Posts
battery disconnect

With my Audi, disconnecting the battery does reset the short-term fuel trim curves in the ECU, and resets the throttle position sensor. The fuel trims are much like the adaptive shifting- it "learns" thru stored driving data. Hard restart (battery disconnect) wipes the short-term memory and resets the adaptation. My Audi is a manual, so cant confirm it works with adaptive shifting, but I'd imagine it works the same way. And no, the seats/radio etc are not wiped when doing this.
 

·
Registered
Joined
·
37 Posts
Re: battery disconnect (JayTeeC)

Hey JayTeeC,<p>I don't mean to hijack this thread, but as a XC90 V8 and A4 owner, this really got my attention. <p>My wife's A4 keeps storing codes that reference fuel trims. Have you seen this? Think disconnecting the battery for a while will make 'em stop?<p> -Paul<br>
 
1 - 7 of 7 Posts
Top