stormseeker 0 Posted March 25, 2004 Had a sit in another VR6 (Storm) last week after I'd given the owner a hand changing the CPS - idle was much much smoother than mine - but noticed while my VAG-COM was plugged in the idle speed was 800rpm. Mine idles at about 680-700rpm - I'm wondering if it's the slightly lower speed that makes mine seem rougher. I've cleaned & checked the ISV and that seems to have made the cold start idle a lot better, but when warm it still seems rough. I know the VR is characteristically rough anyway, but if mine was as smooth as the storm's I'd be well chuffed :-) Both are within spec. but I'm wondering if there was a way to prod the Motronic to increase the idle speed with VAG-COM :? :?: Quote Share this post Link to post Share on other sites
dr_mat 0 Posted March 25, 2004 Which CPS? Crank or Cam? Quote Share this post Link to post Share on other sites
stormseeker 0 Posted March 25, 2004 Which CPS? Crank or Cam? Sorry - cam. That had been changed on the Storm with the smooth idle with which I was impressed... according to the owner it was smooth idling before the cps change too before anyone asks... Quote Share this post Link to post Share on other sites
dr_mat 0 Posted March 25, 2004 Probably the ECU wasn't in fully-adapted mode then, if it's been running without a CPS it'll probably be in "safe" mode. They'll need to reset the ECU after the replacement, I'd say. Mine idles at 650rpm too, it does seem low, but I think that the ECU does that when it's fully adapted. Quote Share this post Link to post Share on other sites
dr_mat 0 Posted March 25, 2004 according to the owner it was smooth idling before the cps change too before anyone asks... Right so it's a fluke then! ;) Quote Share this post Link to post Share on other sites
stormseeker 0 Posted March 25, 2004 Ahhh - I'll check back with him then to see if it's changed... There was a bit of debate between the car's owner and the CCGB technical guru and the consensus was a reset wasn't needed after the CPS change. The CPS fault logged in the ECU was "intermittent" anyway, and the owner reckoned he could tell when it was working and when it wasn't as some days the car felt a lot more "livelier" than others! Quote Share this post Link to post Share on other sites
dr_mat 0 Posted March 25, 2004 The CPS fault logged in the ECU was "intermittent" anyway, and the owner reckoned he could tell when it was working and when it wasn't as some days the car felt a lot more "livelier" than others! I suspect that's just a corrado trait, mine certainly does that, and it's not logged any faults (yet). My feeling on the ECU reset is - if you change anything, do it. It's not gonna cost you anything, and you get to wipe the slate clean and adapt to the current condition of the engine, not how it was six months ago (the majority of the adaptation will occur pretty shortly after the reset). Ask kev about his TPS change - the ECU reset was the only thing that prevented the thing from ticking over at 1200rpm!! Quote Share this post Link to post Share on other sites
stormseeker 0 Posted March 25, 2004 (the majority of the adaptation will occur pretty shortly after the reset). That was the area of debate - certainly things like TPS vs. mass airflow & TPS values for closed & open throttle might be learned then, but mixture adaptation (the legendary "learned O2 values") & some other minor variable bits & bobs were re-learned every 24 (or was it 26?) starts of the engine.... Anyone know any firmware engineers in Bosch :-) ;-) we need a good contact on the inside :lol: Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted March 25, 2004 Might be worth plugging your mates car into VAG-COM and checking what the TPS angle is at idle. If it's greater than 14 degrees, that could be your answer! I did have cursory flick through the VAG-COM manual and it hinted on setting things like idle speeds etc if you know some kind of code, so I dismissed it as I don't have any codes to hand! But AFAIK, the only official way of doing it is setting it on the chip itself. K Quote Share this post Link to post Share on other sites
stormseeker 0 Posted March 25, 2004 I did have cursory flick through the VAG-COM manual and it hinted on setting things like idle speeds etc if you know some kind of code, so I dismissed it as I don't have any codes to hand! But AFAIK, the only official way of doing it is setting it on the chip itself. K Yeah - I saw the "adaptation" section "for modules that support it" like you say, if you know the channel number. I'll have a plough through Bentley (fnarr fnarr) when I get home to see if it's mentioned. Quote Share this post Link to post Share on other sites
Timo. 0 Posted March 26, 2004 Ahhh - I'll check back with him then to see if it's changed... There was a bit of debate between the car's owner and the CCGB technical guru and the consensus was a reset wasn't needed after the CPS change. The CPS fault logged in the ECU was "intermittent" anyway, and the owner reckoned he could tell when it was working and when it wasn't as some days the car felt a lot more "livelier" than others! This was the fault code I once got when plugged into the VAG super computer at my local VW garage. They didn't give a monkeys about the hall sender, but were more interested in the lambda fault, which they cleared. Funnily enough my car behaved like that owners and eventually (actually two weeks ago), in an attempt to sort my car out once and for all, I replaced the hall (cam position) sender and the car has been superb ever since. P.S. never had anymore problems with the lambda sensor. I reckon it was the hall sender all along. Ta timo P.S. its a shame my valve stem seals are away and my vr os going in for engine rebuild this saturday at the cost of a small fortune/small country :shock: Quote Share this post Link to post Share on other sites
HodgyVR6 0 Posted March 26, 2004 Had my discs/pads changed yesterday and my mechanic guy said that he noticed the car was idling slowly 650rpm thus making it feel abit lumpy. He said he adjusted the idle up slightly by about 40 rpm by turning a screw some where. Are you actually able to adjust the idle speed or not on a VR6? I must say I haven't noticed any major difference in the idle speed, but he did say he only adjusted the screw a quarter turn! The guy I use seems to know his stuff so if he didn't adjust the idle speed what was the screw he adjusted? Quote Share this post Link to post Share on other sites
dr_mat 0 Posted March 26, 2004 Erm, can't see how that can work, given that the idle speed is electronically controlled by the ECU. Maybe you can trick the ECU somehow? Perhaps you can overclock the ECU...? ;) Quote Share this post Link to post Share on other sites
stormseeker 0 Posted March 26, 2004 As far as I know there is no screw! ...it's all done with the ISV under the complete control of the motronic ECU. Quote Share this post Link to post Share on other sites
stormseeker 0 Posted March 26, 2004 Erm, can't see how that can work, given that the idle speed is electronically controlled by the ECU. Maybe you can trick the ECU somehow? Perhaps you can overclock the ECU...? ;) Ahhhh that screw - the big brass screw on the side of the ECU ;-) Quote Share this post Link to post Share on other sites
dr_mat 0 Posted March 26, 2004 Don't forget you might need to add a cooling system to the ECU's CPU if you adjust this.. :) Quote Share this post Link to post Share on other sites
stormseeker 0 Posted March 26, 2004 I bunged another 256M of RAM in mine and got another 15BHP.... Quote Share this post Link to post Share on other sites
dr_mat 0 Posted March 26, 2004 Really? I'll have to try that out. My ECU runs Linux, by the way. I got an extra 30 mpg when I switched over from windows, and now the car won't crash! Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted March 26, 2004 Pah you're all pathetic.....my ECU is an XBOX and using the Live service, I can drive it around on the Streets of Project Gotham :-) OK, on a more serious note. You *can* adjust VR idle speed by adjusting the dashpot behind the throttle body. Simply slacken it's 13mm nut and wind it up until the butterfly opens. This is a real cack way of doing it and just introduces one big air leak, and therefore not properly controlled by the ECU, but it must be the only way this mechanic of Hodgy's could have done it as there are no screws on the TB or anywhere else that could effect idle speed. K Quote Share this post Link to post Share on other sites
