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Old 28th September 2016, 02:37 PM
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Default Location of Throttle Position Sensor

I purchased a Throttle Position Sensor and Pedal Position Sensor from the forum sponsors some time back, to try and eliminate some erratic throttle issues. I fitted the Pedal Position Sensor and all seemed well, but I'm still having the same issues (same as HPSauce). I went to fit the Throttle Position Sensor today, but bugger if I can find the existing one. Maybe I need new glasses

I've Googled for pictures but can't find anything relevant. Does anyone have a picture or diagram of where it it located, since the engine bay is in pieces at the moment, and i'd like to get it replaced today, if possible.
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2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds
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Old 28th September 2016, 03:42 PM
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According to the Service Manual for the Motronic system (see Tech Dump) page 62 shows item 10 on the diagram (the black plastic ice hockey puck at the rear upper of the manifold cover) as the "throttle valve control part" (J338) with the throttle valve actuator G186, angle senders 1 and 2 for the actuator (G187 and 188). Does that help?
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Old 28th September 2016, 04:39 PM
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Quote:
Originally Posted by David's8 View Post
According to the Service Manual for the Motronic system (see Tech Dump) page 62 shows item 10 on the diagram (the black plastic ice hockey puck at the rear upper of the manifold cover) as the "throttle valve control part" (J338) with the throttle valve actuator G186, angle senders 1 and 2 for the actuator (G187 and 188). Does that help?
Only partially David. At least it proves I'm looking in the right place. I've removed the air intake pipes right up to the throttle and moved 'item 10' out of the way. I can see the throttle body like this one:

http://www.ebay.co.uk/itm/Audi-A8-D2...8AAOSwbYZXZ805

but can't find where the Throttle Position Sensor is. The one I got from A8parts look like this:

http://www.ebay.co.uk/itm/Audi-A8-D2...YAAOSw9IpXzWot

It doesn't help that most of what I can find seems to imply that the TPS is only on cars with a cable throttle, yet contradict other videos where they suggest the TPS is at fault (slow acceleration) on cars with electronic throttle. Totally confused now!
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2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds

Last edited by steamship; 28th September 2016 at 04:40 PM. Reason: bit in brackets
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Old 28th September 2016, 05:45 PM
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Unfortunately the picture just identifies the "hockey puck" and says "with" the angle sensors but giving no clues as to their exact location. Are angle sensors the position sensors you are looking for?
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Old 28th September 2016, 07:12 PM
ainarssems ainarssems is offline
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I think the separate sensor is only for cable drive and on drive by wire cars it is integrated in throttle body.
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Old 28th September 2016, 08:18 PM
MikkiJayne MikkiJayne is offline
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Yeah agreed ^ That pic is for the 32V versions. On the 40V its all one integrated unit in the throttle body.

Found some pics. 40V unit:



Gubbins under the black cover on the right - the positioning motor itself, plus the sensors.

32V:



Separate TPS on the bottom right.

Last edited by MikkiJayne; 28th September 2016 at 08:22 PM.
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Old 28th September 2016, 11:16 PM
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Cheers. At least that's got that confirmed for me.

Now whilst Googling today about this, I came across a thread on here by Bandycoot about similar issues, which in the end turned out to be a faulty wire. Weather permitting (and now I know what part it is), I may check the wiring to see if there is a fault in it.
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2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds
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Old 14th March 2017, 01:40 PM
HPsauce HPsauce is offline
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Quote:
Originally Posted by steamship View Post
I purchased a Throttle Position Sensor and Pedal Position Sensor from the forum sponsors some time back, to try and eliminate some erratic throttle issues. I fitted the Pedal Position Sensor and all seemed well, but I'm still having the same issues (same as HPSauce).
Hi Sean,
I'm still getting what I can best describe as "twitchiness" but really only when starting from cold. (The sluggishness issue does seem to be resolved by adjusting the brake pedal sensor)

As I have a spare throttle PEDAL sensor I thought I might just try and fit it sometime soon, I'm going back into that area anyway so the knee panel at least will be off for a while. But what was involved in doing the throttle pedal sensor, it's a fairly chunky item with a sprung cable?

I now know how to get the big air duct off, having done that to adjust the brake pedal switch, but I didn't investigate the throttle pedal fittings at that time - it was a nasty cold day! First things first.
__________________
2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!) Oh, and a brand new engine at just under 30,000 miles on the factory one!
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
And before that a lot of Rover 800s, a few oddities, a lovely Triumph Dolomite 1850HL with Overdrive and way back in my schooldays an Austin Seven aka Mini 850!
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Old 15th March 2017, 06:10 PM
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Quote:
Originally Posted by HPsauce View Post
Hi Sean,
I'm still getting what I can best describe as "twitchiness" but really only when starting from cold. (The sluggishness issue does seem to be resolved by adjusting the brake pedal sensor)

As I have a spare throttle PEDAL sensor I thought I might just try and fit it sometime soon, I'm going back into that area anyway so the knee panel at least will be off for a while. But what was involved in doing the throttle pedal sensor, it's a fairly chunky item with a sprung cable?

I now know how to get the big air duct off, having done that to adjust the brake pedal switch, but I didn't investigate the throttle pedal fittings at that time - it was a nasty cold day! First things first.
From what I remember, it was a real pain in the neck (and back!) to do, even more awkward than the brake switch. The three PDFs I've attached are what I used when replacing mine.

Since the only reasonable way to see and do anything in that area is to lie upside with your head in the footwell, and you need both hands to do the work, as well as a couple of different tools, it's a nightmare. I haven't reread the PDFs, but I'm sure the pedal has to be full depressed (I think) when attaching the TPS.

Having managed it, it seemed to resolve my hesitation issues, but as mentioned in your other thread, I suspect this was because I had disturbed the brake switch whilst working on the TPS. Since adjusting the brake switch recently, I haven't had any issues in that area, and suspect that the original TPS was still working fine.
__________________
2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds
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  #10  
Old 15th March 2017, 06:52 PM
HPsauce HPsauce is offline
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Thanks for those Sean. Looks like a right royal PITA job.

I think that I'll do a fair bit of testing the readings first with VCDS, especially when the engine is cold. Can't remember exactly what I was looking at before, but I suspect I got the Throttle and Pedal sensor readings confused as I vaguely recall looking at the ones that went in opposite directions, 0-100 and 100-0. The pedal sensors are the ones where one is double the other, 0-100 and 0-50.
__________________
2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!) Oh, and a brand new engine at just under 30,000 miles on the factory one!
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
And before that a lot of Rover 800s, a few oddities, a lovely Triumph Dolomite 1850HL with Overdrive and way back in my schooldays an Austin Seven aka Mini 850!
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