Plenty of questions pops my head; 1. Is there boost leak on stock diverter valve or turbo hoses got loose? 2. Does ever popular Polo GTI horror stories of the turbo bolts getting loose catch up to the Pocong? 3. Is it one of the early signs of stock K03S going to kaput? (managed to strike this one out as no smoke coming from exhaust upon wot and doesn't sound like turbo whines) 4. Or is it me getting paranoia all over the small stuffs, maybe this whistling just the sign of the engine getting matured, that's all.
Being me, I've got to troubleshoot it asap, otherwise I can't be thinking straight at work and the horror will be hunting me day and night. So yesterday, finally I've make a time (actually 1/2 day EL is more appropriate haha) to face the inevitable Russian roulette.
First appointment of the day is with my usual witch clinic, Auto Reign. The first thing they did was hoist up the car sky high and start ramming to audition Pocong's new crave for whistling.
Minutes after that (which I've lost count how many rams they did), first thing I've been informed is the downpipe's flexy joint is the culprit. It's showing signs of premature aging. Great! Should I change this hollow piece of a miniature tunnel, the CEL will definitely pops up and the only cure to this is I've got to bite a stronger bullet for stg2 poison which involves some other stuffs as well.
And to light up my day, that's not THE problem, it's just A problem. Upon diagnostic scans, the ME7 ECU has reported one error code "Pressure Drop between Turbo and Throttle Valve (check D.V.!)". So they've took out the DV, visibly, it looks clean, Clement even did a blowjob on it and he attest that the DV is working fine. Ok, one less thing to replace.
In the engine bay, there's no clue of boost leaks as all the hoses are all intact, CBV doesn't show signs of doing harakiri for the second time too. They've even took out the turbo to intercooler pipe to check for oil leaks. But again, all is well. The turbo bolts are well tightened too.
So next probable cause then fingered to the faulty sensors - pressure and MAF sensors which are not pocket change price by they way! But no choice we've got to place order and wait these two arrived next week to see if these two will sober the error code or not.
Realising there's still time left, I went to see Ah Heng to get a quotation on custom downpipe. But as I enroute to his place, I made a slight diversion to see another witch clinic, 7th Gear in Sunway.
Azman, the towkey himself took his notebook with vagcom cable to the Pocong and began doing diagnostics again. Hardly surprising enough, he too detected the same error code (they've been using the same VCDS software anyway :) ). Then he took it for a drive around for few minutes and his findings is different. Definitely, there's boost leak! So which witch doctors I need to listen to now?
Came back to the workshop, his boys and he himself making good use of their eyes and ears to detect the leaks. But it's worthless, it's like you're trying to find a small black dot on a wall painted in white!
Just I about to end this long day buy driving the car home do it in another day attitude, Azman got an idea of putting a used, mint condition VF engineering dump valve and see if the error code will disappears. To me as long as the thing can eliminate the error and at the right price, I'm happy to oblige. So, they've began cleaning it up and replace stock DV with this. 5 minutes and the job was done.
Azman then clear the error code prior to my test drive takes place. With the new DV installed, honestly, I don't feel much improvement of power but the boost is more solid, decisive and quite responsive too. But the most important thing to me is to get rid of the error code, the rest was just bonus. And happily enough, it does! Upon diagnostics this time, no error codes came out :)
This solved a problem but the whistle singing is still there (part of it is now down to the new DV :O) but at least I know it's not that severe. Azman, my hat off to you bro! Immediately, a quick call to Clement has been made to cancel off the two sensors but the new ‘plans’ will still get the go ahead. So stay tune, new poisons coming soon and that will solve the whistling too.
The next day upon submitting my leave form to my boss, I've been told "You know 99.99% reasons of you taking EL all these times is because car trouble. I know you're married man but I didn't know you're married to a car instead of woman!" At that point, I was speechless :P