As put on video here: http://www.youtube.com/watch?v=efwJz7Pkzlo Friend advised me to unplug the ISCV, and of course, without it, the engine wouldn't even idle at all then. Is this def. the problem, or is it something else?
i cant see the video, but have you checked the wiring to the throttle switches?, checked all earths are ok, and checked for vaccum leaks
The top throttle switch is fine, that much i can tell, as when you press it, the idle settles down to perfectly normal, but jumps around when you take your finger off the microswitch. Will check the bottom one though. Idles fine when you first start it, but any throttle at all will cause the idle to go mad.
Vac leak somewhere? check for air leaks, you could also set it up using rubjonny's how to set up digi faq
Check all the vac pipes on the Throttle Body, there should be one on the front and one on the back which are blocked off. The other one on the front of the TB should have a T Piece with one pipe going to the FPR then the other going to the air box. To check the switches start the car up, hold the throttle open a little then press the WOT switch. The idle should drop off when switch is pressed. May need setting up as per RJ's Digifant FAQ.
Yep, the switches are both fine, as is the wiring. To clean the ISCV, i just immerse one end in a glass jar full of petrol, while the ignition is on, right? Or have i missed out something?
put it in jar of petrol so that both holes are submerged then turn ignition on. leave it sat buzzing in the jar for a good hour
i had a similar fault on mine when i first got it and had run it for approx 2 weeks. I cleaned the isv and this seemed to make it a little better but also whilst looking for vac leaks i found the rubber 'donut' under the ufo on the rocker cover had split. Of course with me pulling on it and tearing it even more made it worse so it idled worse than yours is doing. I replaced it and the idle pretty much stablised, although it was a tad high. I then found that with the throttle shut it wasnt hitting the idle switch correctly because at some point the stop had been wound in too far. Adjusted the throttle stop and its idled at approx 900rpm everytime since.
Wow - in the 50 mins its been immersed and 'gibbering', its thrown out a fair amount of crap... Fingers Crossed!
I *think* it's all sorted now, thanks chaps Here's the video i recorded: http://www.youtube.com/watch?v=NaOeWbTQ1Gs
Contrary to my earlier assumption - it's still fecked To start it, you NEED throttle, once it started, it'll sit at 900rpm, steady idle, and gently raising the throttle will be fine, and come off the gas and it'll be back at 900rpm. Now, at about 2250rpm, the engine is stuttering and misfiring, until you get to about 3500rpm, at which point it'll zip to 6500rpm without issue, and smoothly, too. But, then the idle will settle down to 1500rpm and won't go any lower. Turn the car off, start it back up again (with the prerequisite throttle), and it'll sit at 900rpm again - but again, after driving it, it'll never go below 1500rpm again. If i adjust the idle screw at 1500rpm so it sinks lower, it'll start doing the surging crap again, and upon restart, will barely keep idle at 400rpm or so. AAARGH!
sounds like a mixture problem. set CO and timing as per rubjonny faq. before you do that you might wanna take throttle body off and give it a good fettle with carb cleaner. make sure the hole between inside of throttle body and vac line with T is clear(pipe cleaner works well).
I'll give it a go, however, i do have a timing light - would it not be easier to set the timing with that?
Have you tried fitting another ISV? There does come a point when cleaning doesn't work anymore, if you know someone with a working 8v that'd be a good start.
Had thought about it, there are a couple of them on eBay but all used....new ones are silly money, from what i can see. Before i do anything though, i have to clean up the sand underneath the car...stupid oil change!
Another possible reason, Coolant Temperature Sensor? The one on my Mk3 is being a pig as well, so i ordered one from GSF, along with a new distributor cap, rotor arm, ignition lead set and on a more unrelated note, new front shocks & springs...
Hi mate, i had a similar problem on my old mk2 PB and spend a small fortune on leads, plugs, dizzy cap/rotar arm and it turned out it only needed the throttle body cleaning out. I don't know if youve already done this but if you aint its worth a go, and will only cost you a couple of quid for some carb cleaner and twenty minutes or so. I hope this helps. Steve
