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  #1  
Old 20th August 2018, 05:45 PM
quattrofrank quattrofrank is offline
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Default Throttle position wrong

Hi

I have an 97 3.7q with the aew engine.
When checking with vagcom I see that the motronic doesnt recognise that I have full throttle.
I have adjusted the cable and checked that the throttle flap is fully open when I press.
Have tried the ignition on, press throttle for 20sec etc and it doesnt work.
Also tried the rosstech procedure but there is no label file for my engine so no luck.
When I press full throttle vagcom says only 75% and recognise it as part throttle.

Any suggestions? I have ordered a new tps but it seems unlikely that it work fine except for the last 25%
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Old 20th August 2018, 05:56 PM
HPsauce HPsauce is offline
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Which sensors are you looking at?
There are pedal position sensors and throttle body sensors, not sure what your engine will have though.
IIRC there are two readings on each with opposing scales and I'm not sure either gets to 100% anyway….
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Old 20th August 2018, 06:02 PM
quattrofrank quattrofrank is offline
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I belive my engine only have tps since there is a cable throttle not a drive by wire system. Anyhow the ecu should recognise full throttle so there is something wrong.
I gues I can try to measure the resistance between the plugs on idle and wot, but I cannot find any data for this for my engine.
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Old 20th August 2018, 06:08 PM
HPsauce HPsauce is offline
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Have you done a Throttle Body Alignment? https://www.youtube.com/watch?v=2zrmhDw_v7Y
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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".
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.
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  #5  
Old 20th August 2018, 07:51 PM
quattrofrank quattrofrank is offline
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In group 98 there is nothing, only error.
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Old 20th August 2018, 08:33 PM
Regulus Regulus is offline
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I looked in my manual, and it seems to be a correct reading (if I understand the manual)

Servicing accelerator linkage - vehicles with electronic throttle system (electronic power control)



5 Acceleration position sender -G79

RHD vehicles
Requirement for test: Accelerator pedal stop installed (combined with kick down switch for vehicles with automatic gearbox)

01 - Engine electronics
select diagnosis function “08 - Read data block” from the menu.
enter “062” to select Display group 062 and confirm entry.
Check display in display zone 3 (accelerator pedal position).

Vehicles with automatic gearbox
Press the accelerator all the way down (past kick down point)
Specification: 70 … 74% (accelerator pedal pressed down past kick down point)

Exit from function “08 - Read data block”
Select diagnosis function “06 - End output”.
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Old 20th August 2018, 08:43 PM
quattrofrank quattrofrank is offline
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Thank you, alltought I see that this is for right hand drive and electronic throttle. I have lhd and cable throttle.
But maybe it is correct that it will not show 100% when fully pressed. Still kinda strange that vagcom shows only part throttle and not full throttle when fully pressed.
Found this under Measuring blocks and then group 4
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  #8  
Old 20th August 2018, 08:51 PM
Regulus Regulus is offline
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Oh sorry, I just assumed you had a RHD, that's why I posted that
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  #9  
Old 21st August 2018, 06:25 AM
ainarssems ainarssems is offline
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Block 1, zone 3 is actual reading, should be 5-10 with throttle released, 80-98 at full throttle. Block 4 zone 1 should be the same, block 4, zone 2 is learned value and should change from 0-100. 75 is a bit out of spec so possibly it does not learn it correctly. You could try loosening the bolts and turn potentiometer in relation to throttle a little bit.

Throttle body potentiometer resistance pins 1-2 1.5-2.6kΩ at idle, pins 2-3 0.75-1.3kΩ at idle, 2.4-3.6kΩ at full throttle.
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Last edited by ainarssems; 21st August 2018 at 06:30 AM.
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  #10  
Old 21st August 2018, 08:00 AM
quattrofrank quattrofrank is offline
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That is excellent info.
Actual reading is7.9 with closed throttle and learned is 0.
With full throttle actual is 83.2 and learned 75.2.

Will measure and see what results I get. Hopefully the new tps will sort this.
I have adjusted the tps so that the idle switch is triggered excactly when throttle flap is closed (maybe 0.2 degress before so not much at all)
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