GolfGTIforum.co.uk
Model specific boards => Golf mk2 => Topic started by: hughesy83 on 01 August 2009, 23:55
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Hi,
I bought my first mk2 16V not long ago and am having fun to say the least!
Unfortunatley tho now i've now got a small problem with the revs not dropping back to idle between gears, and wonder if anyone here could offer advice.
As an example, if i'm driving along the motorway in 5th at 70 and depress the clutch, the engine still runs away at about 3200 rpm and doesn't drop in speed.
If then I approach a junction or whatever and have to stop, the only way to drop revs and not sit there sounding like i'm revving the nuts off my car in an attempt to impress the ladies in car next to me, is by engaging clutch again and forcing revs down. But once they are down, they dont rise back up by themselves - they just seem to get "stuck" up there.... this can happen in any gear...
I was wondering if its the ISV unit? although other stories i've read on here RE: ISV mention either erratic idleing or revs dropping below 1000 and stalling so i'm wondering if something else is up with my car?
And btw i do take my foot off the throttle lol, and don't think its a sticky throttle cable as i can drop the revs using clutch as mentioned above...
Cheers for any advice...
Hughesy
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Is your clutching slipping.
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Could be the idle switch on the throttle body is not operating when you take your foot off the throttle or the isv sticking. Just had this exact prob on an 8v digi and it turned out to be an intermittent isv fault, replaced the isv and it was sorted. I know the 16v kjet is is different but I think the ISV works in exactly the same way. On the 16v there's a separate electronic control box for the isv behind the centre console but I've not heard of these going wrong very often. Always worth cleaning the isv out with some carb cleaner, there's a guide on here somewhere.
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sounds throttle related. whats the cable like? it might be frayed and its sticking at this point, on the springs and linkages are sticking.
i had the same problem when i put an abf in mine, the top of the throttle linkage was jamming on the bonnet :laugh:
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Try unplugging the ISV - idle will be pretty rough, but if it stops revving, that's your problem!
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No clutch isn't slipping.
I'll try unplugging the ISV now and see what happens... thanks for the tips!
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Any idea what this is? Its been attached to my ISV using a plastic tie clip.
It appears to connect fuel lines and a sensor (temp?) But i'm pretty sure this isn't how car left the factory. Any idea's on whats going on here? Thanks
(http://i602.photobucket.com/albums/tt110/hughesy83/02082009065.jpg)
(http://i602.photobucket.com/albums/tt110/hughesy83/02082009066.jpg)
(http://i602.photobucket.com/albums/tt110/hughesy83/02082009067.jpg)
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Looks like some sort of by-pass or piggy back on the warm up regulator, perhaps to enrich the mixture for some reason. Perhaps the cams or timing are not standard?
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you can test your throttle switch by hand, with the engine running open the throttle by hand to over 2k rom, press the button on the throttle switch and hold it. if working it will activate the bypass valve and the rev's will temp plummet then lift again. it will do this continually for as long as you have the button pressed. if it dont do it, the switch is goosed
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Have your brakes got harder lately? Check the NRV between the brake servo and the induction and also check the interity of the servo pipe. Any leaks there may cause the symptoms to have.
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looks like you have the good version of k-star that can control fueling as well as ignition advance, nice :)
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where does it inject the extra fuel? looks like the fuel line goes behind the engine
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seems what it does is change the control pressure, as its tapped inline to the WUR. Much better way to do it rather than have an extra injector spray fuel in :cool:
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ah i see
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So its a good thing by the sounds of it? :grin: But what does WUR stand for? :huh:
The prob isnt that serious, she still runs well. But I could prob save some fuel by sorting it.
Gambit - will check the throttle button - cheers
DarnPB - no probs with brakes
Ta all :smiley:
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warm up regulator, basically its the equivilant of the choke on a carb but it doesnt function in the same way, but its how the fueling is ajusted while the car warms up. trouble with k-star is its quite old, so finding tuners who can set it up is getting dificult. but at least you have the deluxe package there if you find someone, or if you go back to std/fit another engine its worth a few bob!
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Hi all,
I thought i would just add to this topic rather than start another as i am having the same problem on my car.
My car is now converted to ABF and all running fine except at random intervals the revs decide to drop very slowly, seem to be more likely to happen once the car has warmed up.
When going slowly in town or approaching a junction and down shifting you have to bring the revs down with the clutch and brake, but if i depress the clutch the revs begin to rise again.
I have sinced cleaned the ISV which i thought sorted the problem, which it hasnt but it does seem to have helped slightly. When on the open road and pulling 4k+ the revs hardly drop between gearchanges, but then a little bit of cruising at below 3k and it seems ok.
i have also tested the idle switch and that is fine. is there any chance this could be lambda probe related as mine is secondhand and unknown?!
tomorrow i plan to recheck the throttlebody and cable but im pretty sure the problem isn't there, i will also try unplugging the ISV.
any help very much appreciated
cheers
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Thing that fixed this for me was a faulty temp sensor, on the side of the head are 3 individual ones, swap them around on the wires and one of them will be running different to the rest. You should see it on the dash temp sensor. Don't know why this causes the high revs but mine did it on and off for a while, I tried everything and then just on a hunch I swapped the temp sensors round and it never happened again. I mean I tried everything as well, ECU ignition amp, ISV Control box, ISV, metering head, WUR the works. bloody £3 temp sensor solved it :D
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Thing that fixed this for me was a faulty temp sensor, on the side of the head are 3 individual ones, swap them around on the wires and one of them will be running different to the rest. You should see it on the dash temp sensor. Don't know why this causes the high revs but mine did it on and off for a while, I tried everything and then just on a hunch I swapped the temp sensors round and it never happened again. I mean I tried everything as well, ECU ignition amp, ISV Control box, ISV, metering head, WUR the works. bloody £3 temp sensor solved it :D
Didn't have a chance to look at her today, but i will look into it tomorrow!
Have found out today that if i drive at under 3k it doesnt do it at all, so that has solved it for now.
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could be a sticky over-run valve, this unit is supposed to cartch the revs if you dip the clutch at high rpm. check the vac hose and electrical connection to it. also check the idle siwtch carefully, it might click normally but if the cable or upper mech is slightly stiff it might prevent the top arm actuate the switch sometimers. i had the same problem on my cabby, bit of spray lube down the accellerator cable solved the issue for me.
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could be a sticky over-run valve, this unit is supposed to cartch the revs if you dip the clutch at high rpm. check the vac hose and electrical connection to it. also check the idle siwtch carefully, it might click normally but if the cable or upper mech is slightly stiff it might prevent the top arm actuate the switch sometimers. i had the same problem on my cabby, bit of spray lube down the accellerator cable solved the issue for me.
Where is the over run valve? an chance anyone has a picture of it?
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its behind the airbox, big black/grey plastic thingy, can just see it in this piccy:
(http://i.ebayimg.com/20/!B(22CY!B2k~$(KGrHgoOKjcEjlLm(,PeBKed!U)5uQ~~_12.JPG)
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mines running propper management, digi 3. dont think i have that do i?! :huh:
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ah no, in your case id be looking at the idle switch on the back of the tb, its the 2 pin jobber. should hear it click as throttle is shut, ive seen the nipple clicky bit fall off on them. worth havign a hunt aroujnd for air leaks too, and check the tps & idle switch wiring as it runs above the zaust and gets baked.
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I have already checked the idle switch and ceaned the ISV. the TPS is next on my list to check.
Will vagcom be any use?
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its behind the airbox, big black/grey plastic thingy, can just see it in this piccy:
(http://i.ebayimg.com/20/!B(22CY!B2k~$(KGrHgoOKjcEjlLm(,PeBKed!U)5uQ~~_12.JPG)
hehe, im watchin that metering head on ebay!