ADY hesitance and power loss.

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kevtherev
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ADY hesitance and power loss.

Post by kevtherev »

Just a few niggles with my recently fitted ADY.
Rough idle, bogs under load, then at 3000rpm its all back.
New bosch Lambda, replaced with OE
MAF cleaned, replaced with OE
TB cleaned
TPS cleaned, mechanism checked
FPR renewed
CPS renewed
New cap
Arm
Plugs
No vac leaks


Because of the hesitation and poor performance, I put it on the VCDS cleared some older historic faults, reset the timing, cleared that fault too.
I was left with 'O2 sensor at upper limit' fault.
I tried another known good O2 but it was the same.

Now I have noticed that the TPS opens and closes the throttle butterfly indefinitely, or until I start the engine.
Then when switching off, it starts again.
Like it's looking for something.

This fault doesn't appear on VCDS but my question is could it contribute to the poor running?
AGG 2.0L 8V. (Golf GTi MkIII)

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Titus A Duxass
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Re: ADY hesitance and power loss.

Post by Titus A Duxass »

Kev, you need to pair the throttle body with the ECU. 
You can only do this with the paid for version of VCDS or by taking the van to a local garage and asking them to do it for you. 

I can't remember if you can do it with OBD 11 or not. 

It takes about 10 seconds once you have the engine up to temp and have no fault codes present. 
VW T3 GTi Camper 2,0l

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kevtherev
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Re: ADY hesitance and power loss.

Post by kevtherev »

Cheers pal
I'm having that done next weekend.

Getting there..
AGG 2.0L 8V. (Golf GTi MkIII)

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kevtherev
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Re: ADY hesitance and power loss.

Post by kevtherev »

Just to finish this.
I had the engine on the VCDS and it couldn't talk to the throttle body.
Clearly there was an issue with the connection.

So I changed the entire throttle body for another from a 16v
The VCDS recognised it.
Switched on and it set itself.
Now the tickover is steady, acceleration smooth and there's no bogging.

It's a night and day fix.
I now have a full power ADY under my foot.
Driving the van has once again become a pleasure.
I fitted an Auspuff catylitic intermediate pipe to use the old WBX silencer.
It's quietened down considerably too.

Thanks Titus..
AGG 2.0L 8V. (Golf GTi MkIII)

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Titus A Duxass
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Re: ADY hesitance and power loss.

Post by Titus A Duxass »

Great news Kevin. 
I have also experienced throttle body failure. 
I now carry a spare one. 

I love to see some photos of the exhaust set up, I really need to find a quieter solution. 
VW T3 GTi Camper 2,0l

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Re: ADY hesitance and power loss.

Post by davidoft1 »

Because the throttle body was faulty the faults not always shown on the scanner, gotta go old school with a oscilloscope

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kevtherev
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Re: ADY hesitance and power loss.

Post by kevtherev »

Titus A Duxass wrote: 10 Dec 2020, 05:46 Great news Kevin. 
I have also experienced throttle body failure. 
I now carry a spare one. 

I love to see some photos of the exhaust set up, I really need to find a quieter solution. 
I used a German intermediate exhaust into WBX single entry silencer.
Company is
https://www.auspuffhannover.com

I haven't got an image host.
AGG 2.0L 8V. (Golf GTi MkIII)

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kevtherev
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Re: ADY hesitance and power loss.

Post by kevtherev »

AGG 2.0L 8V. (Golf GTi MkIII)

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kevtherev
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Re: ADY hesitance and power loss.

Post by kevtherev »

Image

:roll:
AGG 2.0L 8V. (Golf GTi MkIII)

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Aidan
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Re: ADY hesitance and power loss.

Post by Aidan »

Image


with your mouse right click on the picture you want to use and choose copy image link, then in the forum posting dialogue click the picture icon (screen with a plus bottom right) and paste the link into that, simples

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kevtherev
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Re: ADY hesitance and power loss.

Post by kevtherev »

Cheers mate.
I was trying to do it from a smartphone
AGG 2.0L 8V. (Golf GTi MkIII)

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Re: ADY hesitance and power loss.

Post by silverbullet »

Just an observation: very few (possibly only one that I have seen) of these inline exhaust adaptor/downpipes have any appreciable secondary header length (the "downpipe" bit)
This is an important part of engine and exhaust tuning and the secondaries need to be the same length as the original exhaust in the donor vehicle.
Otherwise you are just nobbling the engine and it will not reach its full potential because the exhaust pulses wont be tuned to the inlet..
Longer pipes can also make for a quieter exhaust.

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kevtherev
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Re: ADY hesitance and power loss.

Post by kevtherev »

I really haven't noticed any appreciable difference in power from the wbx 2.1 (on a carb) and this ADY.
Im sure a dynograph would prove you right though.
The only notable difference is in where on the rpm scale you get the full grin.
The DJ delivered it in the lower half, whereas the ADY really picks its skirt up at 3200 and keeps going to 5

Another notable fact is this pipe has a diameter difference..and a cat..
The intermediate pipe is larger than the WBX silencer inlet
So much that the inlet flange had to be remade and welded to the silencer.
I'll be experimenting with a JX silencer next.

Finally I fitted this engine for other reasons than performance.
Longevity, reliability, and most importantly accessibility to standard garage services to use the OBD port.
I'm getting 28 mpg @ 70mph (average) approximately so there's a difference there too.
AGG 2.0L 8V. (Golf GTi MkIII)

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