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Discussion Starter · #1 ·
Hi all

Ive popped over from the Corrado forum for some advice.

Im currentlyt running a 4motion engine, with custom-code, in my VR6 Corrado. I have a slight problem with the DBW, I think.

This is what I posetd on the corrado forum: http://www.the-corrado.net/forum/viewtopic.php?t=48134&highlight=


Right, since I had
the engine done (I think anyway) Ive always had a sharpish jerk from
the car when I take my foot of the accelerator.

Its like taking your foot off really quickly, and the car jerks,
just once, but in all gears, and no matter what revs, or if being
driven hard or slow.

I cant think of another way to describe it
Confused


Double-6s had a go and felt it (oo er) and I also asked H100 VW
and he reckons it sounds like the fuel is being cut off when I take my
foot off, and then back on straight away. Does this sound right?


Oh yeah, its not a massive jerk, but it does make you move forward like a sharpish gear change.

Another thought:

The brake or clutch switches are not fitted, but they do not get depressed for this to happen, so
therefore if the switches were fitted they would be passive anyway.

Do you reckon it could be the custom-code chip causing it? My mate
reckons it sounds similar to the digilag that mk 2's used to suffer
from, but obviously on a DBW car.

Any thoughts?


Any help appreciated guys.

Stan
 

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Sorry, I've got a 4mo, but can't help other than to say mine doesn't do this. However, I think I've read about faulty brake light switches causing problems so might be worth looking into that aspect (do a search perhaps). You made need to effectively 'plug one in' even if its not being used?

Otherwise are you able to plug in VAG-COM? and read for faults?
 

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Discussion Starter · #4 ·
Yeah I'll have to get the vag com on it again then see if I can spot anything. I know the brake switch isnt fitted as its still running the Corrado brakes, same for the clutch too. However the accelerator from the 4mo is fitted.
 

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hi

did you find a fix for this? i think its the same thing happening to mine right now

all off a sudden when i take the foot of the gas it jerks forward, seems like the fuel or air to engine is being cut off as soon as

vag-com didnt show anything

hafizur
 

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Discussion Starter · #6 ·
No mate I didnt, however its booked back in at PSI Tuning next month. Its not a huge judder, more of a small lunge, if you know what I mean. Its quite hard to describe unless you drive it.
 

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Yep, i know what you mean, was out on a long hard drive on sunday, parked up and filled up with texaco crap. So wondering if that has anything to do with it. Only happens once the engine has warmed up though. Feels like the whole engine is loose and may fall off.

Let me know what PSI tuning say, i'm going to try replace some motor mounts and reset the ecu. I'll let you know if i get mine fixed too

Thanks

Hafizur
 

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Just double checked with VAG-COM and i am seeing the following:

16885 - Vehicle Speed Sensor: Implausible Signal

P0501 - 004 - No Signal/Communication - Intermittent

16891 - Idle Control System RPM Higher than Expected.

P0507 - 001 - Upper Limit Exceeded - Intermittent

From doing a search on these errors, it seems be the speed sensor thats causing this and the jerking forward. Any one know where it is located on the R32?

Just checked the climatronic and channel 16 read 0 all the way for 10 miles. The car is not getting a speed signal, so it stops sucking in air the moment you take the foot off the gas. Cruise control is not working either. Maybe the cluth pedal has gone dodgy, i know the cover came off (The .:R Logo) on Sunday. Hmm, wondering if i have other issues, as when i have the headlights off, the car behaves as normal, as soon as i turn the lights on, it starts to do the jerky nesss and cruise doesnt work.

Anyways, looks like its a common problem but no definite answer, will check all things this evening. Speed sensor, Clutch Pedal, Brake light switch. Can't think of anything else.

Come on, someone must have the answer to this.
Hafizur
 

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just checked the maf and throttle body, seems like a lot of dirt on the throttle body

damn it, just started raining. oh well, guess i may have better luck tomorrow

anyone point me to a throttle body removal thread?
 

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easy.

unclip the inlet hose

unplug the electrical connector for the DBW

remove the 4 bolts

can't belive you had to ask, just look at it, it's blatantly obvious how it's held on.
 

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wooooohooooo

after careful search, found the speed sensor, took it out and gave it a good clean with a cloth and air blower, put it back in, and went for a drive. So far so good, going to get it replaced as soon as, as i am sure it will go soon.

This thing really messes your car up.

The throttle body needs a good clean though, and the maf, but i saw a big difference between driving with the maf on and maf off, it was not really possible to drive with the maf off.

Now to change the motor mounts and arbs

hafizur
 

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that didnt last long

no longer working again

maybe that isnt the speed sender

time to take to the dealers i guess

hafizur
 
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