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Boost dropping hugely - Recirculation valve or Wastegate?

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If you're temp sensor is playing up it will confuse the fueling which will have a knock on effect to the running of the car. Might as well replace it if it's suspect they don't cost much. Not sure how it would play a role in the 17705 though but they can do strange things...

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Fair enough, I've just ordered a new one which should be here this Thursday. 

 

We'll see how it goes from there.

The gauge doesn't tell the full story unfortunately

I really hate meters that don't show accurate values!

I really hate meters that don't show accurate values!

I know what you mean, suppose most drivers would rather see a stable gauge knowing that when it isn't bang on the middle there definitely is a problem.

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What exactly would be reporting the 90 degrees to my dash if not the temp sensor?

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I've swapped out the the temperature sensor and I've also temporarily fitted a Manual boost controller parallel to the n75 (to bleed off boost spikes) this has stopped the earlier mentioned boost-drop. Does this give anyone any ideas on what it might be?

Which did you fit first and did you try one thing at a time?

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I did the mbc parallel first which sorted the engine at high rpm. (I tuned it to 22psi so it didn't over boost)

The temperature gauge was added after and hasn't made a noticeable difference.

The more I talk about this I'm really starting to think it is a software issue or maybe my injectors can't flow 23 psi worth of fuel

If it can do 22 psi without issues then it strikes me that the map is asking for too much, and that is what it should be mapped to. Don't get me wrong I'm no expert on mapping but I feel a bit of common sense kicking in.

I think if I were you I'd be thinking I've scratched my head enough and I'd be going back to the mapper, get it taken off and get a refund and go elsewhere. Whether it's their fault or not at least you'd have a new baseline to work from.

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If it can do 22 psi without issues then it strikes me that the map is asking for too much, and that is what it should be mapped to. Don't get me wrong I'm no expert on mapping but I feel a bit of common sense kicking in.

I think if I were you I'd be thinking I've scratched my head enough and I'd be going back to the mapper, get it taken off and get a refund and go elsewhere. Whether it's their fault or not at least you'd have a new baseline to work from.

 

It's a strange one because I know that the k03s can boost higher than 23 psi / 1.5 Bar, although it's pushing it's limits, I know of a golf 1.8t k03s that's pushing 1.7bar with ease. 

 

I realise this issue has gone on long enough, but the thing that's making me reluctant to the refund is that my car went in to soft limp mode as stock (though it obviously didn't boost high enough to hit this engine stutter). 

 

I'll have to have a good think about this one, thanks for the input by the way.

Edited by Martin191

You may have sold the stock map limp mode with stuff you've done trying along the way. Problem is you won't know that until you get it back to baseline on the stock map. Be tempted to be sparing with that story if you talk to the mappers and just say you want it off and back to standard. At the end of the day I don't think they should have mapped it in the first place...

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You may have sold the stock map limp mode with stuff you've done trying along the way. Problem is you won't know that until you get it back to baseline on the stock map. Be tempted to be sparing with that story if you talk to the mappers and just say you want it off and back to standard. At the end of the day I don't think they should have mapped it in the first place...

Some wise words, I'm going to drop in this Saturday to see if they can refund or fix this for me.

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May have found the source of my problem... 

The last two days I've had a bad engine stutter, got it back home and scanned it with Vagcom and found that it had the Fault code -

16706/P0322/000802 - Engine Speed Sensor (G28): No Signal

The symptoms of this pretty much explain the issue I've been having minus the limp mode problem ( 17705 )

I'll be getting another one tomorrow and hopefully also fitting it tomorrow.

 

Secondly, I've also managed to get a hold of V12 Tuning, I'm going to have a chat with them tomorrow and hopefully get them to fix the problem or refund me. 

May have found the source of my problem... 

The last two days I've had a bad engine stutter, got it back home and scanned it with Vagcom and found that it had the Fault code -

16706/P0322/000802 - Engine Speed Sensor (G28): No Signal

The symptoms of this pretty much explain the issue I've been having minus the limp mode problem ( 17705 )

I'll be getting another one tomorrow and hopefully also fitting it tomorrow.

 

Secondly, I've also managed to get a hold of V12 Tuning, I'm going to have a chat with them tomorrow and hopefully get them to fix the problem or refund me.

Sounds promising mate, looks like the ecu finally decided to tell you something you can work with!

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Tell me about it! Its only taken it 2 months to throw a code!

Could this cause a knock on effect that triggers the 17705 code?

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Had a nightmare trip back from work yesterday, ended up having to drive it in first and second gear for 10 odd miles to keep the rpm high / to stop it from conking out. 

 

Bought and fit a new sensor today though and it starts! which is a huge improvement from yesterday! I can't take it out for a drive due to being blocked in on the road I'm parked on, but idling seems a fair bit smoother too, if it can effect that.

It would effect idle surely so hopefully it's a step in the right direction

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Just took it out for a quick spin, unfortunately couldn't get up to speed to see if it still stutters, but It ran like it used to, and it didn't go in to limp mode either (though that could have just been a luck of the draw) I'll have to report back in a day or so once I've taken it out for a drive a few more times.

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So everything is running well on the crank sensor front, but the 17705 fault still persists!

It's been booked in to see the guy who remapped it this weekend, but out of interest would a faulty map sensor cause this, and if so, how would I test this?

I would have thought a faulty MAP would do more than just throw a code, and if it did it would probably directly relate to it. I could be wrong though. Only way to test the MAP is swap one in I think.

If it's still pulling that code and crank sensor has improved things I'm still inclined to think the remap isn't helping, or could be the root cause. You say it was pulling g that code before remap though? Can't remember you saying but did you check all pipework?

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I would have thought a faulty MAP would do more than just throw a code, and if it did it would probably directly relate to it. I could be wrong though. Only way to test the MAP is swap one in I think.

If it's still pulling that code and crank sensor has improved things I'm still inclined to think the remap isn't helping, or could be the root cause. You say it was pulling g that code before remap though? Can't remember you saying but did you check all pipework?I boos

I can pressurise and hold 30 psi between the turbo and the intake manifold so I highly doubt it's an air leak. Also block 032 was showing 0.8 in the left hand field :) 

 

It would go in to limp mode on the old map without a manual boost controller installed. But If i'm honest I think that's because the guy who remapped just told the ecu to boost 15+ psi without the ecu requesting it. Causing the overboost limp mode.

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Finally found my problem, after all this time it was the suction jet pump...

I did the suction jet pump this morning after reading that it can cause the error code 17705 that I've been experiencing. Straight after removal my car was more responsive and didn't have the air rushing noise it used to have when coming on boost.

Also want to redeem V12 as although vital checks weren't made, he was dedicated to his service and was adamant it wasn't a software issue, which turned out to be correct.

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May have spoken too soon, after 4 cold starts with it being fine, the 5th put me in limp...

 

O well! The throttle response is much better and it boosts a lot harder without that stupid suction jet pump now anyway.. The brakes also seem unaffected. 

Hmmmmm the plot thickens

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