Re: V6 Tickover
Posted: Tue Feb 24, 2009 11:16 am
Very useful info there, Andy - and I do like your expression "marketing over substance"apole wrote:Hi there,
I have the same issue, suddenly one day in the summer the idle speed dropped to around 500 RPM. Fine normally, but sometimes if the AC cuts in etc it can stall. I have LPG but this is not connected as it does the same on petrol.
There is an idle control valve on the V6, researching the web it could be that this is gunked up and needs cleaning/replacing. Details of what is looks like are here:
http://www.yiparts.com/Part/en/RHFHF
It is however, very hard to get at. I'm therefore wondering if it's worth using some kind of foam inlet system cleaner, again this gets good reviews but that could be marketing over substance but I think it's worthwhile.
This is the cleaner:
http://www.ecotekplc.com/PowerBoost.htm
Over time I have cleaned most of the electrical contacts on the engine (spray contact cleaner from maplins, and if poss fine wet dry paper) and ensured all things like earth connnects, ECU plugs etc are clean and well seated. I have yet to clean the MAF but will do so when it's warmer and I have time.
I'm also going to check all the vacuum hoses around the engine to ensure there are no leaks there.
I can't see the Lambda sensor having anything to do with the idle speed, or the MAF as they control mixture.
I have had my codes read and there is nothing registered, if you do it is possible to see the Lambda sensor, temp sensor etc in action.
I am awaiting a new disty cap and rotor arm, not sure if this will help the idle, but my car recently started missing sometimes (another story) and on investigation the contacts on the cap are very worn/burnt on some, and the rotor arm looks like an old sponge. Just cleaning it a bit has made a big difference, much more power and no missing so I'm hopeful that the new parts will make it run better. Can't see that improving the idle speed however.
Have you any other symptoms, how is your MPG for example? Are all your plugs and air filter clean, what colour are your plugs? Check the disty cap as a precaution, some get water contamination and mine was quite worn so it's worth checking anyhow.
Some web links I found for diagnosis ideas are:
http://www.unixnerd.demon.co.uk/motronic.html
http://www.2carpros.com/first_things/wh ... t_idle.htm
If I find a solution I'll let you know.
Andy
As a one time marketeer (not a lifetime career, I hasten to add), who knows their evil ways well 
, that's a recurring theme for me - but not previously as elegantly as you put it. If you don't mind, I'll borrow the expression for future use!Our V6 has also started running rough when below normal operating temperature, and now also has that tendency to stall at traffic lights when cold(ish) - but only on LPG.
To prevent that happening, I've been manually controlling the switchover from unleaded to LPG, when my TM-2 engine temp monitor gets up into the 70s - and that has worked fine as a workaround. Next week, I'm down in Dorset, where Imperial got the LPG conversion done, and I'm going to call in for my, long overdue, "first 1,000 miles LPG check up/tune up", and hope that properly fixes it - will confirm on here.
Must admit also that it's a North Japan 'cold climate' model, and I hadn't set the air intake to 'cold' through the recent freeze but it probably wasn't that, as it's still been doing it, although perhaps a little less(?). Changed the lever over to 'cold' last night, and if I do find today that it's made any difference, I'll report that on here.