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Discussion Starter · #1 ·
It's running not bad at all, the rhythmic misfire is gone.
It has, however, got a 'whistle' at about 3/4 throttle (play the video, not the whole video, just til the noise is apparent)

https://photos.app.goo.gl/eUFTtxAc6m5Z3Sqt5

Kirsty drove it this evening and managed to get it into limp mode - took a screenshot of all the error codes.
I reset the codes and drove it back home. Ragged it a bit. No limp mode and just 1 error. Pic of that too.
Suspect @northpole will be the main responder (thanks in advance dude)
e03f1a65176a9608fc9ab9252faf5e30.jpg
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The p0638 fault code in its various forms is usually related to the throttle position sensor or its related diagfram or butterfly valve or if fitted the vacuum hoses attached to them .
Now exactly what the problem could be on these depends on what type of upper manifold you have fitted. Do you have an upper manifold with the TPS fitted there or is your tps on the throttle pedal itself?
- If you have the tps on the manifold then i would suspect that the manifold is itself gunged up and needs a clean , make sure the butterfly valve inside the manifold can move freely also clean the boost sensor. Don't remove the tps sensor from the manifold leave in position

- The next stage is to check your vacuum hoses for signs of perishing/cracking , a very common problem on these DTi,s .
best solution is to replace them with silicone tubing 3 metres of 3mm tubing is enough to do all the vacuum hoses around the engine bay

PS what program did you use to pull those error's?
 

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Discussion Starter · #3 ·
Torque Pro.
The sensors are new and genuine.
Vacuum hoses have already been replaced
The whole inlet was cleaned, its all as sparkly as it's ever going to be.

I'm not overly concerned about the remaining code..
That whistly screechy noise, though, is a concern.
 

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But did you check the tips sensor on the pedal I'm quite sure yours is on there... as with your engine being the y22dth it'll be on the pedal.. and that might've seen better days. Or needs a clean out...

Long story short remove dash panels under the steeringwheel and check that big connector on the gas pedal for dirt or broken isolation on the separate cables. If that all checks out you'll need to replace the sensor itself. Means pulling the pedal unless you like being in an awkward position not being able to see what the hell you are doing.. but it can be done... just akward
 

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Ps the noise might be the turbo but it doesn't have to be luckily the turbo's for the dti engines are cheap as chips... you just need to find a good used one. last time I was looking I found that they went for max 50 pounds on ebay.. actually i just checked myself and they are double the price as yours does have the VNT mechanism on it ... unlucky but that is what makes them more expensive...

Used or fully refurbished (no surcharge or replacement needed to be send i return, it is what i would go for)
 

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Discussion Starter · #6 ·
I'll check out the pedal sensor when summer returns.. cant find it on 7zap but have found it, and a part number, via Google.

Wouldn't a turbo issue produce other symptoms?
It's not particularly down on power, there's no smoke under acceleration or at any other time, no turbo related fault codes (apart from that 1 pending one when it went to limp and cleared ok).

If it were a vacuum leak, which I do think it sounds like, is it likely to only happen at about 3/4 throttle and then go away?
 

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Discussion Starter · #10 ·
It sounds like a boost leak!
Yup.. We eventually arrived there (we've never heard a boost leak before).
Can't find any leaks anywhere though. Checked all pipes and connections to/from the turbo and all seems well..

Next step would be bull bars off, bumper and grille off, go through it all again with a finer toothed comb.
 

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It's like a squeal though, inlet gasket?

A smoke tester/pressure tester would be handy. Doubt it's the turbo as it's only started doing it, rather something you've played with.
 
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