Nick Barnes Posted January 10, 2017 Share Posted January 10, 2017 Hi I have a 2000 1.6i it was running a bit rough and when idling would go from almost cutting out to running fast sometimes especially when first started from cold . I changed the idle control valve ( pain in the a... you have to have very small hands and eyes on stalks to see and find the bottom bolt when refitting so its tightened properly, ended up with 2 of us one above and one under the car to get a spanner on it to get the new one back on !! taking the old one off is easy as you can undo the top bolt then swing the sensor out of the way while attached by the bottom bolt so you can get to it OK to undo it ) and took it for a test run, now much smoother but if I put the clutch in before stopping it will go down to an idle speed of 1500 RPM while I am still moving ? until I actually stop it goes down to 1000 ? the RPMs stay steady now so why the delay in dropping to the correct RPM Any ideas Quote Link to comment Share on other sites More sharing options...
jinks Posted January 12, 2017 Share Posted January 12, 2017 clean throttle body could be sticking loob up the acc linkage as well if not ok then possible tps sensor regards john Quote Link to comment Share on other sites More sharing options...
Nick Barnes Posted January 12, 2017 Author Share Posted January 12, 2017 clean throttle body could be sticking loob up the acc linkage as well if not ok then possible tps sensor regards john Hi John, Thanks I will spray the throttle body with carb cleaner and do the linkages, I already took off and cleaned the throttle positioning sensor with wd40 ? when I changed the idle control valve, it wasn't doing this before I changed the ICV so maybe this one is also at fault ? the old one was just not running at idle properly where this one is ( except the 1500 RPM thing ) lucky I kept the old one and just cleaned it with carb cleaner, so if the problem persists I might put the clean old one back on to see what happens ? but what a pain to get to it do it haha Quote Link to comment Share on other sites More sharing options...
jinks Posted January 12, 2017 Share Posted January 12, 2017 is your icv the one on the side of the inlet or sits on the iner wing Quote Link to comment Share on other sites More sharing options...
Nick Barnes Posted January 13, 2017 Author Share Posted January 13, 2017 is your icv the one on the side of the inlet or sits on the iner wing Hi Jinks, It's on the right hand side of the throttle body at the top Quote Link to comment Share on other sites More sharing options...
Nick Barnes Posted January 13, 2017 Author Share Posted January 13, 2017 Hi Jinks, It's on the right hand side of the throttle body at the top no its not haha thats the throttle position sensor ( sorry got confused ) the ICV is on the front of the throttle body behind the engine held on by 2 x 8mm bolts in that small gap, you cant see the bottom bolt until you undo the top bolt and swing the unit up then you can see the bottom bolt and get a spanner on it easily ( that's how I got it off ) But trying putting it back in hmmm the unit needs to be in situ to fully tighten it ? and you cant see the bolt neither can you get a hand in the gap from either side because of all the pies etc. to feel the bolt properly ? so you can get a spanner on it unless you a vey small handed contorsionist. We ended up with me under the car threading a spanner up through the gaps in the various pipes, to my mate with a screwdriver trying to locate the spanner on the bolt from above by feel haha not a pleasant experience and would like to know the secret of getting it back on ? Quote Link to comment Share on other sites More sharing options...
Paul Grainger Posted January 14, 2017 Share Posted January 14, 2017 Hi Nick. This is normal...... Sounds weird I know. The idle speed is supposed to hang up until the car stops, this it controlled by the ecu and speed sensor. Disconnect the sensor and it won't happen. the sensor is mounted on the gearbox and the Speedo cable goes into the top of it. The multiplug is directly above it on the baulkhead. It has three wires and is basically a hall sensor. Many of these sensors gave a problem of idle speed hanging up when stationary due to power leakage within the hall sensor fooling the ecu into thinking the car was still moving when it wasn't. Only thing is the speeds you have quoted sound a little high. Could your rev counter be reading wrong? Normal tick over speed is 800 rpm Cheers Quote Link to comment Share on other sites More sharing options...
Nick Barnes Posted January 14, 2017 Author Share Posted January 14, 2017 Hi Paul, Thanks for the input, the high RPM when coasting has seemed to have sorted itself out last time I drove her ? I never noticed a car hanging up or doing this before that's why I questioned it ? The revs drop down to NML idle revs now ? when you put the clutch in and coast to a stop no hanging ? I did take off the TPS again ( as its a 2 minute job ) and gave it another squirt of WD40 maybe that helped ? maybe the ECU had to reset itself fully and now that has ? The idle has now settled down to about 950 RPM, I will try to manually adjust the idle down to 800 RPM later if this is possible ? but the Haynes manual says this engine ( zetec ) can't be adjusted without specialised equipment because its controlled by the engine management system ? it also doesn't list a RPM for this engine ? lets hope its sorted now and thanks again for the message Quote Link to comment Share on other sites More sharing options...
Paul Grainger Posted January 15, 2017 Share Posted January 15, 2017 Hi Nick, Don't try and adjust the idle speed. The ecu records the lowest voltage as a base value. Have you scanned for any fault codes? Quote Link to comment Share on other sites More sharing options...
Paul Grainger Posted January 15, 2017 Share Posted January 15, 2017 Just a thought. Is there any hissing noise when ticking over? Could have an air leak in a vacuum pipe. The t piece at the front of the engine on the right as you look at it is quite a common failure. Also worth replacing the pcv valve where the breather pipe goes into the block. Sometimes these play up too. Good luck. Quote Link to comment Share on other sites More sharing options...
Nick Barnes Posted January 18, 2017 Author Share Posted January 18, 2017 Thanks for the ideas Paul I will look at these things Keep you posted when I've checked them Quote Link to comment Share on other sites More sharing options...
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