law262 0 Posted July 30, 2010 its the device that is connected to the boost pipe going to the throtle body. measure the 2 outer pins with an ohmeter. to adjust: if there is a blue cap remove this and turn untill you get 500ohms. how does that work? Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted August 16, 2010 its the device that is connected to the boost pipe going to the throtle body. measure the 2 outer pins with an ohmeter. to adjust: if there is a blue cap remove this and turn untill you get 500ohms. how does that work? I didnt see your post untill just now, I take it I adjust it off the car? its reading 37ohms at the moment, no blue cap just a hole with a big black flat head screw in it. Quote Share this post Link to post Share on other sites
JMC 0 Posted August 16, 2010 its the device that is connected to the boost pipe going to the throtle body. measure the 2 outer pins with an ohmeter. to adjust: if there is a blue cap remove this and turn untill you get 500ohms. how does that work? I didnt see your post untill just now, I take it I adjust it off the car? its reading 37ohms at the moment, no blue cap just a hole with a big black flat head screw in it. When you checked your resistnce, did you do that hot? The 500 ohm recommendation is when the car is up to temp. Adjust it when the car is up to temp mate. Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted August 18, 2010 its the device that is connected to the boost pipe going to the throtle body. measure the 2 outer pins with an ohmeter. to adjust: if there is a blue cap remove this and turn untill you get 500ohms. how does that work? I didnt see your post untill just now, I take it I adjust it off the car? its reading 37ohms at the moment, no blue cap just a hole with a big black flat head screw in it. When you checked your resistnce, did you do that hot? The 500 ohm recommendation is when the car is up to temp. Adjust it when the car is up to temp mate. cheers il give it a go Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted August 18, 2010 I set it at 500 when it was cold and off the car, its 504 hot on the car, guess i need a new one then, unless its that small a change normally? never seen a thermistor that changes that little. Quote Share this post Link to post Share on other sites
JMC 0 Posted August 18, 2010 No, normally a bigger change than that (between ambient and operating temp). Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted August 18, 2010 Thanks, I thought so, off to VW again then lol Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted August 19, 2010 Just ordered one from VW, £80 :cry: and the last one in the UK Quote Share this post Link to post Share on other sites
sparks 0 Posted August 20, 2010 i was told to always set it at 500 on cold cus everyone car can run differently at hotter temps hence the set when cold someone tech out there to clear this up maybe ??? stu ... Quote Share this post Link to post Share on other sites
JMC 0 Posted August 20, 2010 Strange, I was told to set when hot. The Bentley manual has the CO pot at about 400 ohms when hot, but nearer 3000 ohms at 20 degrees. This would tie in with setting it when hot. Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted August 21, 2010 well its got the new last and expensive replacement on it and it has made... no difference :epicfail: unless they arnt set up when new. but im thinking it might be the throttle body switches now, as if it has the flat spot it wont accelerate atal, but if i lift of compleatly then put my foot down again it works :shrug: Quote Share this post Link to post Share on other sites
JMC 0 Posted August 21, 2010 I doubt they come with the right resistance setting from the factory. Did you try setting/measuring it when warm again. With all the correct pipework in place for the ISV, and the new CO pot set to 500 ohms when warm, have you tried going throught he full correct way of setting the idle (up to temp, blue temp sensor disconnected, adjusting the idle screw on the back of the throttle body, revving 3 times to more than 3000rpm etc)? The ISV itself shouldn't need to be adjusted, atleast it is unlikely to be the cause of your idling woes. Quote Share this post Link to post Share on other sites
steveo29 0 Posted August 21, 2010 thrott switches take 5 mins to check with a multimeter Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted August 23, 2010 I doubt they come with the right resistance setting from the factory. Did you try setting/measuring it when warm again. With all the correct pipework in place for the ISV, and the new CO pot set to 500 ohms when warm, have you tried going throught he full correct way of setting the idle (up to temp, blue temp sensor disconnected, adjusting the idle screw on the back of the throttle body, revving 3 times to more than 3000rpm etc)? The ISV itself shouldn't need to be adjusted, atleast it is unlikely to be the cause of your idling woes. hi iv re connected the isv and the idle rises and dropps a few hundred rpm constantly (every second) what is the full way to set the idle? i cant find it on here, thanks. Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted August 23, 2010 Also, with the isv out of the car, i cab blow a small amount of air through it, is it ment to be like this or should it be sealed? i cant get it compleatly sealed by adjusting the grub screw in the end of it. Quote Share this post Link to post Share on other sites
JMC 0 Posted August 23, 2010 You should be able to blow through the ISV when out of the car. Idling adjusting flagrantly nicked from the Vortex website... Idle Speed / CO Content --------------------------------- 1) Pull crankcase breather hose off pressure regulating valve and turn it so that only fresh air will be drawn in. 2) Let engine run at idle. 3) After approximately one minute disconnect the blue connector at the coolant temperature sender. 4) Raise the engine speed four times to over 3000 RPMs and then let the engine return to idle (This cancels the hot start idle increase function). 5) Adjust if necessary. 6) Remove tamper resistant plug over the CO screw, rotate both adjustment screws alternately. --- the idle speed is 800 30 RPMs --- and the CO is around 1.2 % (or set CO pot to approx 500 ohms) 7) Reconnect the blue temperature sensor harness plug. 8 ) Raise the engine four more times to over 3000 RPMs and then let the engine return to idle. 9) Check to make sure that the CO did not go out of specs. --- If the CO is out of specs, check the oxygen sensor system. 10) With the settings correct shut off the engine and reconnect the crankcase breather hose. 11) Install a new tamper resistant plug over the CO adjustment screw. Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted August 23, 2010 :notworthy: thanks Quote Share this post Link to post Share on other sites
JMC 0 Posted August 23, 2010 That's alright mate. With the ISV try and set it back to how it was originally with the grub screw. I seem to remember with mine it was at about where the air flow was minimum when blown through while off the car. To be honest if they have moved over their life, it'll be minimal, and should need very little if any adjustment. Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted August 23, 2010 Iv got 2, iv adjusted one but not the other, I get the same results with both though :( Quote Share this post Link to post Share on other sites
JMC 0 Posted August 23, 2010 That pretty much confirms that it's not the ISV then. Have you checked the ISV wiring for damage - mine had burnt through where it got close to the head which caused my idle problems. Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted September 27, 2010 ....... Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted October 12, 2010 I removed the ISV, and heard a whistling noise from the throttle body, the vac pipe to the ecu had split and come off, i think it was intermittent when it was just starting to go, and then constant when it came off, so iv re fitted it (about 2cm has come off the end so i still need to replace it) and it seams to be running better than ever, even managed 41mpg on a run at the weekend :D but the vw parts department showed the pipe as many parts, not one pipe, and they have ordered a few pipes in but none are the right size :( edit new pipe fitted (thanks mimjed) it seamed okay for a while but its doing it again, ECU relay on order :( Quote Share this post Link to post Share on other sites
leeeeshad 0 Posted October 24, 2010 The ECU relay sorted it :D Quote Share this post Link to post Share on other sites