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simex
23-10-2006, 07:32 PM
Has anyone ever had the problem where their car jerks slightly when taking your foot off the accelerator pedal? :?

It seems as though when I take my foot off the pedal, the car revs a little by its self. This happens in all gears and at throughout the entire rev range.

I have a 2001 VW golf GL 1.6

Thanks :)

william
23-10-2006, 07:40 PM
it could be a number on things my opinion is that it may be a clutch or airflow meter how many ks has the vehicle done

simex
23-10-2006, 07:50 PM
it's on 100,000 km's

i don't think it's the clutch, for the reason that it happen in neutral. (reving slightly as i take my foot off the pedal)

It could possibly be the air flow meter.

william
23-10-2006, 08:14 PM
the best way to check the airflow meter is to just disconnect the connector plug and see if the idle changes ,this just happens on idle if so i could be a misfire caused but cheapo fuel so use premium bc it fowls up o2 sensors what is your location i can put the car on the computer and i can give u an instant fault its hard to determine as the 1.6 simos engines have many faults that can cause other faults

william
23-10-2006, 08:18 PM
melbourne hmm to far also check coolant temp sensor to check if green plug if so fault may not be in temp sender unit but start there as is cheapest part all of 50 dollars where the air flow meter is 350 including labour

simex
23-10-2006, 08:39 PM
thanks for the advice William, I will have a look at those things you mentioned.

It could also be something to do with the accelerator cable. Just as i release the pedal, whether i'm in gear or not, i feel i slight "kick" in the pedal.

Could be the cable getting stuck...?

william
23-10-2006, 08:51 PM
uncommon but may be the case the best way to check that is by pressing the accelerator they pulling it back up if the revs change you know the cable need adjusting i cant recal if u can adjust on throttle body

Bug_racer
24-10-2006, 04:46 PM
It can be adjusted outside , it works the same way as mk3's .

I think its none of these problems .
My thought is the throttle body itself .
If the throttle position sensor (tps) is playing up then the engine ecu will not use this cause its outside its tolerances and use the MAF and Lambda probe to adjust the throttle instead . Since the MAF and lambda dont react as quick as the tps you will get bucking and jerking . A quick test is to see if the cruise control still works .

simex
24-10-2006, 05:40 PM
sadly i have a GL and don't have cruise control.

what would a throttle body set me back $$ ??

h100vw
24-10-2006, 11:07 PM
http://www.ecstuning.com/stage/edpd/pagebuild_v2.cgi?make=Volkswagen&engine=1.8T&model=Golf%20IV&submodel=&category=Engine&subcategory=Cooling

A bit cheaper from the states.

Gavin

mikinoz
25-10-2006, 12:06 PM
I have recified this fault myself on my 1.6.

You go to the point on the acc. cable where it emerges at the throttle body end, you take the clip off that retains it, pull it so that it is not opening the throttle, but tight and then return the clip back.

It somehow loosens, and this fix sorted me out for 20000km now.

You will also get better throttle response now. Maybe give the throttle body a clean too... why not ! ;)

gtimk5
25-10-2006, 02:19 PM
The main thing is to make sure you are not getting full throttle before the pedal hits the floor as no doubt the cables aren't cheap! If you don't check this then you are straining the cable every time that you apply full acceleration. That is a bad thing! :o

simex
25-10-2006, 02:28 PM
Thanks Mikinoz, that will save me some money if it works.

GTIMK5: In order to prevent the cable from undergoing any strain, should i just increase the height of the stopper under the pedal?

gtimk5
25-10-2006, 02:33 PM
Yes, you sure can. That is an option. However, you shouldn't need to adjust that if the cable is set correctly. Cheers, Andrew:)

polak
26-10-2006, 12:26 AM
Ive once had this exact same problem on my 2000 1.6 GL. However funnily enough before i knew it the problem had actually fixed itself. It just topped doing it.
Good Luck with it

simex
26-10-2006, 05:48 PM
I had a good look at the car today and noticed that there is a bit of slack in the throttle wheel (The wheel that connects the the cable, i'm not sure what the technical name is). This means that as the throttle is fully closed, there is still some spring left in the wheel, which causes the jerk, as it springs to its resting position.

Mikinoz: This is why your method of tightening the cable worked, as it took up the excess slack in the wheel.

Is there any way of adjusting the throttle itself to reduce this slack, instead of tightening the cable?

Thanks everyone for your input so far, I have only had my golf for 5 days and still trying the figure the car out. I will post some pics soon.

mikinoz
26-10-2006, 06:04 PM
I have wound mine so that all of the slack in the wheel 'linkge?' has gone, but the throttle has not opened.

inherently there is going to be some movement in the throttle by it's design ie. a pivot, but I have not experienced any detrimental effect from doing this... You will also find that it may engine brake more smoothly, as mine was jerking under engine brake loads also.

I spose in the old days with downdraght carbs, it was closed when it was slack as gravity took care of it.

WE WANT PICS SIMEX!

simex
26-10-2006, 06:13 PM
i tried to tighten the cable like you did, but when i got to the last rubber slot and it couldn't be tightened anymore, there was still slack in the linkage.

That's why i need to adjust the actual throttle wheel itself.

gtimk5
26-10-2006, 06:28 PM
Not sure what you are doing simex. To do it Mikinoz's way you only need to adjust the small amount of play in the cable out of it. If the throttle isn't opening at all then your cable is either broken or disconnected off the pedal? Sounds like you need to get it looked at by an expert?
My airfares are reasonably cheap!!!! :D

MK2 GTI
26-10-2006, 07:02 PM
i have had this and a simple clean out of the throttle body fixed it, though it could be anything.

simex
02-11-2006, 06:10 PM
Problem solved:

I tried all the methods that were mentioned in this thread (cleaning the throttle body and adjusting the cable), but they didn't eliminate the problem.

Today I took the car down to Volkspower in Burwood for a computer diagnostic test and 2 errors were found
1. Throttle position sensor
2. Air mass/Air flow sensor

They pinned down these errors to the temp switch green D plug ($50 part) and it eliminated the problem. The car was then put on the diagnostic again and all the errors were cleared.