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Blown turbo? Maybe?

1131

Passed Driver's Ed
The idea is to jam the screw driver in the brake caliper so that it prevents the disc from turning, never did it myself but as I have to replace the CV boot that's what I found. As for the gear, D will not work but P should prevent the wheel from turning (but I would get a second advice if it's OK to do it with an auto, on a manual it's fine at least). Note that without an impact you should crack the axle bolt with the wheel on the ground (remove the center cap)
Sorry for the delay in responding. We were on holiday here in the states. Neither D nor P arrests the CV axle on a DSG. However, sticking a screwdriver in the brake rotor vent right at the caliper does work.
 

1131

Passed Driver's Ed
So I ended up having to cut the turbo mounting bracket in half. It was not fun having a shower of sparks just inches away from my face, but a Dremel 4000 and an EZ456 wheel made short work of it. I also tried to cut a slot in the bolt, but because I couldn't see what I was doing working upside down in the dark, my cut was off-center so that plan was doomed to failure.

I will post feedback on the various steps of the Pelican guide in a later post but for now...

I put everything back together and started the car. There was a lot of smoke for the first few minutes but it settled down and started to smoke less after that. After about 15 minutes of idling, the smoke was mostly gone, so I assume it was still burning leftover oil in the intercooler.

Then I went for a test drive. There was some smoke upon initial hard acceleration. Again I assume that was just residual oil. After a few moments the smoke stopped. I drove for a mile normally, then attempted a big hill. Immediately there was a problem making power. The car started to shake. I turned off on a side road. After a while the car completely died. Pending DTCs were related to random misfires and system too lean.

I thought it might be bad spark plugs since I was using garbage Autolite double plats -- the only plugs Autozone had in stock. Examining them, I saw that they were gapped to between .040 and .045 which seems rather high for a turbo application. So I regapped them to .028. Made no difference. I then went to Carquest and purchased a replacement set of NGK plats for $57. It also made no difference. When I try to start the car now, it makes exactly the same sound as it does during a compression test. It's as if the spark plugs aren't even there.

To review, it's definitely not the battery, starter, or plugs.

I'm going to try disconnecting the battery for 30 minutes or so today. If that doesn't work I'm going to try cleaning the throttle body and MAP sensor. I'm on Audi coilpacks which should be bomb-proof. But I'll also try swapping the coil packs with older VW coil packs. I may order a crank position sensor as well. If these don't work, I will have it towed to VW and have them do a diagnosis. ($100 for the tow and $125 for the diagnostic.) I've been reluctant to do this because I'm convinced my VW dealer is one of the worst in the country for ripping people off.

This saga has really dragged on. I just want my car back. <Sigh>
 
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1131

Passed Driver's Ed
Not sure if it's worth mentioning, but my tach was bouncing around like crazy for like the first two minutes after starting the car. Then it settled down and started behaving normally.

Also, for my turbo first-start procedure, I attempted to start the vehicle with the coilpack loom disconnected. I did this twice to get oil circulating in the turbo. Then, after reconnecting the loom, I started the vehicle and let it idle for almost an hour before doing any kind of driving.

And yes, I remembered to put oil in the turbo itself before re-attaching the oil line. It only needed maybe 50ml worth through the top hole.
 
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vwengineer

Ready to race!
Location
Switzerland
Congrats for the installation of the turbo! I would investigate system too lean first, you might have a vacuum leak somewhere. Did you check the fuel trims (LTFT) to see how bad it is? Are the misfires on a specific cylinder or all of them? The good thing is that apparently you took care of the oil consumption issue. If you find a vacuum leak, repair it and delete all the DTCs then (which will reset fuels trims also).
 

1131

Passed Driver's Ed
Congrats for the installation of the turbo! I would investigate system too lean first, you might have a vacuum leak somewhere. Did you check the fuel trims (LTFT) to see how bad it is? Are the misfires on a specific cylinder or all of them? The good thing is that apparently you took care of the oil consumption issue. If you find a vacuum leak, repair it and delete all the DTCs then (which will reset fuels trims also).
Thanks. I would be in more of a mood to celebrate if my car made it more than 2 miles before dying. Would a vacuum leak prevent a car from starting? That's where I am right now. I need to be able to start the car. Getting it back to top performance is something I can work on over time. I know my MAP and TB are still fouled from the blown turbo, but these wouldn't prevent a car from starting.

The cylinder misfires were random and the DTCs were only "pending" and not recorded. And it happened only on the big hill.

I'm racking my brain for all the things that can prevent our cars from starting. I'm pretty sure I've eliminated battery, starter, plug, and packs. What does that leave? I'm thinking CPS or one of the fuel pumps. I've already ordered a CPS that is coming in Monday. I may clean the MAP and TB on Sunday since I will have time to kill waiting for the CPS.
 

1131

Passed Driver's Ed
One other small detail. The old turbo was a revision F. The new one is a revision G. Could this make a difference? What kind of difference? And would it prevent my car from starting? Why did it start once then?
 

vwengineer

Ready to race!
Location
Switzerland
Yes a vacuum leak can prevent the car from starting, happened to me when my N80 was stuck open, it took several tries to start the car. Not sure about the turbo revision but it will not prevent the car to start for sure.
 

GTI's

Go Kart Champion
Location
MD
Is this car running now or is it turning over like if the plugs are removed and spinning fast than usual not firing up.
 

1131

Passed Driver's Ed
Is this car running now or is it turning over like if the plugs are removed and spinning fast than usual not firing up.
It's as I described in post #22. It's the same sound as you get when you do a compression test with the plugs removed. It's as if there is no spark at all. At this point I feel like it has to be the CPS. There's nothing else that controls spark. Plus it died on a hill. In the cold. AND my tach was jumping around like crazy on first startup. All these are classic bad CPS symptoms.
 

1131

Passed Driver's Ed
Yes a vacuum leak can prevent the car from starting, happened to me when my N80 was stuck open, it took several tries to start the car. Not sure about the turbo revision but it will not prevent the car to start for sure.
Thanks. I did not know that. I have a backup N80. I'll throw it on if the new CPS doesn't fix it.
 

GTI's

Go Kart Champion
Location
MD
It's as I described in post #22. It's the same sound as you get when you do a compression test with the plugs removed. It's as if there is no spark at all. At this point I feel like it has to be the CPS. There's nothing else that controls spark. Plus it died on a hill. In the cold. AND my tach was jumping around like crazy on first startup. All these are classic bad CPS symptoms.
And your scan tool can not look at the CPS while cranking to see if its working or not??
 

1131

Passed Driver's Ed
And your scan tool can not look at the CPS while cranking to see if its working or not??
I'm using the Torque app. I don't believe it can do that. Can VCDS do it? I may be able to borrow/rent a VCDS from someone. But by then the new CPS will have arrived. What measuring blocks should I be looking at and what does a normal reading look like?
 

GTI's

Go Kart Champion
Location
MD
I'm using the Torque app. I don't believe it can do that. Can VCDS do it? I may be able to borrow/rent a VCDS from someone. But by then the new CPS will have arrived. What measuring blocks should I be looking at and what does a normal reading look like?
Yes Vcds can look at that sensor in multiple MB/AMV..............01 Engine --> 001.1 or 002.1 or 003.1 and at least 10 more locations

While cranking engine it will show the speed/ rpm the starter is turning the engine, somewhere in the 200 range and a running engine at the idle rpm or rpm the engine happens to be at.
 

1131

Passed Driver's Ed
Allllllllrighty then. So I managed to get ahold of a VCDS. I turned the key to the accessory position, fired up the software, opened the engine module, opened the measuring blocks and clicked "Go!" after groups 001, 002, and 003. All fields populated with zero values and showed green. Then I cranked the engine and got what you see below. Is this the smoking gun? Did I guess the diagnosis and get it right? Or am I more deeply effed than I realize? I have a sneaking feeling it's the latter. What else should I look at while in VCDS?

Looks like the new CPS isn't arriving until tomorrow late. Plus it's gonna be raining. So I won't be able to get to it before Tuesday. I've postponed cleaning my MAP and TB until I get this other situation worked out. I may have to pull the battery and top it up at home since I think the voltage has been drifting down while it's been sitting there in the freezing cold for the past four days. Might as well optimize my chances at a successful restart.
g28.jpg
 

vwengineer

Ready to race!
Location
Switzerland
Thanks. I did not know that. I have a backup N80. I'll throw it on if the new CPS doesn't fix it.
This was just an exemple that a vacuum leak could prevent the car from starting, if you didn't touch the N80 I don't see any reason of it to fail now
 

1131

Passed Driver's Ed
Vcds is on version 19.6.2 so download the newer free version here https://www.ross-tech.com/vcds/download/current.php unless you have got an illegitimate cable in which case don't and take what it scans with caution.

Have you done an Auto Scan saved it and tried to clear DTC.

So it turns out... if your battery voltage drops too low, VCDS starts to behave funny. I removed the battery and charged it at home. It still won't start the car, but according to VCDS my CPS (G28) is just fine?

cps ok.PNG


I'm going to swap it out on Sunday anyway because... what the heck else could prevent my car from starting? It's not the plugs. It's not the starter. It's not the battery. It's not the coilpacks. The engine appears to be fine. I can hear it turning over, and I confirmed this by manually turning it with a 19mm socket.

Once again I'll be relying on a Pelican guide for the swap:

I don't know what exact vehicle Pelican dude is working on, but I'm guessing it's not a GTI. The oil filter is totally in the way. I've already tried jiggling the CPS connector to get it out of the bracket, all the while whispering under my breath pleasedontbreakpleasedontbreakpleasedontbreak. And. Of course. It's started to crack. Just the bracket though. So I've decided to stop messing with it until I can drain the oil and remove the filter. I'm waiting until Sunday because the rain is supposed to move on by then. So you guys have until then to correct my thinking and direct to me to something else I haven't considered.

I'm just about ready to throw in the towel. If I can't start the car by Sunday night, I'll bite the bullet and have it towed to a VW dealership and have them diagnose it. Kills me, but whatchagonnado.
 

1131

Passed Driver's Ed
Is it just me or has this forum been down more often that it's been up recently? I guess I should hurry up and update while I have this oppo then.

So it seems VCDS was right. There was nothing wrong with my CPS. Also, I apologize for using the acronym CPS. Apparently CKP is the preferred acronym on the internets so that there is no confusion with the CAMshaft position sensor.

There was about a quarter cup of oil that drained out of my charge pipe when I removed it. Oil, when it's in smoke form, goes wherever it wants I guess. The TB was remarkably clean. But I cleaned it some more anyway using CRC's TB and carb cleaner. The hardest part of this procedure was removing the TB hose. It's a 2-piece jobby. It's a band clamp that threads through a ring sleeve that's crimped onto the hose. It's ridiculously difficult to remove, even maximally loosened. I needed 3 pick tools. Also. Be super super careful about how much force you use to remove this hose. Your dipstick holder, IAT, and TB connector are all very fragile and right in the same vicinity. My TB connector was a casualty.

broken tb.jpg


Fortunately, it was just the connector, so i crazy glued it back together. But it broken again as I re-installed the radiator fans that I removed to make room. I have it duct taped together at this point.

With the charge pipe removed, there is enough room to remove the CKP without having to remove your oil filter. The 6mm hex bolt holding the bracket for both the CKP and knock sensor was seized. I hit it with some Liquid Wrench and let it sit overnight. I came back at it in the morning with a T40 t-handle wrench and it finally relented. The Pelican guide suggests that the CKP pops right out after removing the 5mm hex holding it in. It does not. I needed to grab it with channel locking pliers to get it out.

I was unable to clean the MAP sensor. One guess as to why. Yup. The two philips head screws were completely rusted. I hit it with some Liquid Wrench and let it sit overnight. No difference. With the charge pipe removed, I was able to Dremel a slot into the screw. I then proceeded to torque the heads of both screws completely off. Now, if I want to clean or replace my MAP sensor, I will have to drill these two screws out. Since I'm not sure what size screw this is, I decided to leave it be for now. It's unlikely that a bad MAP sensor would produce a no start condition. I was only cleaning it since I was in the area, and it was a good oppo.

So with TB cleaned and new CKP? Still no start.

So a thought occurred to me. I pulled the coilpack loom, the coilpacks, and the spark plugs. I then inverted the loom and reinstalled the coil packs onto the inverted loom. I installed the spark plugs onto the inverted coilpacks. That way, I could check for spark from within the cabin while trying to start the car. I did this test at night for maximum visibility. All four spark plugs are working. That means the entire ignition system is fine: battery, starter, loom, coil packs, and spark plugs.

I think I now need to investigate the fuel supply. Possible culprits are HPFP, LPFP, fuel pump relay, fuel filter, and injectors . It's not likely to be the injectors since it's unlikely that all four would fail simultaneously. It's not likely to be the fuel filter since I changed it back in the summer. I ordered a used HPFP which should arrive after Christmas. So I have some down time to think and to try stuff.

Here's a snapshot of my 103, 106, and 230 MBs. This is with the engine off because, like I said, the car will not start. Still, there seems to be a rather large discrepancy between requested and actual, no?

fuel.jpg



There are two things that bug me:

1. There have been NO DTCs concerning fuel supply issues. Are any of these parts that are likely to die suddenly while driving?

2. Isn't it peculiar that it happened immediately after my turbo swap attempt? I mean, suspecting the CKP seemed reasonable since it controls spark and the old one was indeed slightly covered with oil when I replaced it. But would a blown turbo cause a fuel pump to fail? That seems harder to believe.

Like I said. I'll have a few days to ponder things, so I'd appreciate any feedback I get on my dilemma. Provided, of course, that the forum doesn't go down again and you're able to read this at all.
 

zrickety

The Fixer
Location
31709
Ride
09 GTI
I may have missed it, but have you done a compression check? There could be something going on that's not electrical...
 

1131

Passed Driver's Ed
I may have missed it, but have you done a compression check? There could be something going on that's not electrical...
See post #1. I did one recently while diagnosing the blown turbo and it came back 190 in all four cylinders. I haven't done one since the turbo swap though so maybe I should. I am able to turn the engine manually using a 19mm socket so the engine is not seized.
 
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