Date: Wed, 30 Jul 2003 18:07:29 GMT From: Paul Halliday <pjghnopsamyonder.co.uk> Subject: Re: Mixture problems and lumpy idle
in article bg8ckm$lu9il$1nopsam52899.news.uni-berlin.de, Grunff at grunffnopsam.com wrote on 30/07/2003 13:10: > Paul Halliday wrote: > >> Am I going the right way about this? The Haynes says to set the idle first. >> Am I doing this right? It then says to set the mixture correctly by >> measuring the exhaust gas. Is there something I can buy to check this? I >> have no cat, so I presume I can measure the gas at the rear of the car at >> the exhaust outlet. > > As Carl says, check the cold start injector - they sometimes > leak. Remove it when the engine is hot, see if it dribbles. > > Have you cleaned out your idle control valve (by the thermostat > housing)? If not, remove it, empty half a can of carb cleaner > into it, followed by a generous amount of WD40. You will see > lots and lots of soot coming out. > > Have you cleaned out the throttle body + butterfly? Again, lots > of carb cleaner followed by a bit of oil. Do I understand this right? If the cold start injector is not running at all then while the car is warming up it won't be rich enough. This will explain the poor RPM at cold idle and occasional stalling when when the outside weather is a bit muggy. If it is over running (running all the time), then I've set the mixture too lean to compensate when warm and the same outcome as above will be so? It all seems to have started since I had the dump valve fitted and my throttle housing replaced for a 16V version to accommodate the dump valve. I've ruled out the dump valve leaking by plugging up the pipe. Perhaps my garage were over-zealous with the cold start valve gasket sealant :) I'll have them check it out when it's next in - I ended up burning myself when I last bled the coolant, so spraying petrol all over myself from a leaking injector seems a really bad idea :) I do clean out the PCV, idle control valve and throttle body with carb cleaner the day before doing an oil change. I do a Wynns engine flush (to get the remaining crap out) and oil change about every 3000 miles. Sparks and leads are checked at this time as well. I've recently checked over the rotor arm, cap, leads and plugs when I had that "wobble at 2000 RPM" recently, so I know that's all okay. Thanks for the help guys, Paul <--- Contemplating that petrol fiasco now I've had a beer :)
![]() |
![]() |
![]() |
![]() |
![]() |