Volkswagen TDI talk

[anderson750]

I agree with Greg about checking all the boost piping. It is also common for a significant amount of an oily mess to collect in the intercooler. I would take all this apart, clean and check all the connections and piping.

 

[zukgod1]

I would take off the intake hose at the manifold and take a look inside. Those are infamous for plugging up and causing exactly what you are describing.

 

[Greg]

Just did another test run to try the boost theory, manifold pressure goes to 30 and holds until I hit the said RPM band then drops and starts to slowly rise so I don't think its boost being lost. I tried lugging the motor and the manifold pressure holds all through the rpm until it gets to the 2700ish mark. I made a really crappy video of the scan gauge and didn't realize I bumped the rpm to volts until I was done. Commute traffic was building so I decided to abstain from another distracted WOT run until traffic lightens up. I brought up the clogged manifold theory to my mechanic friend and his opinion that would probably show more through the whole band. its really feels normal and then just straight up falls on its face.

[video=youtube_share;d7gJrh27Wpk]https://youtu.be/d7gJrh27Wpk[/video]

Hmmm.... if it seems to be building & holding boost, then the next thing I'd look at is inside the intake for carbon build up.

 

[Unimog]

That is as much boost as it is going to give. Sounds exactly like clogged intake that mine exhibited around 250k. No problems until you need higher top speed. Mine got worse until it wouldn't hold 55mph on steep grades anymore, but it was pretty much fine at lower speeds.

I had the intake cleaned out and it is like a new car! The local VW dealer offers cleaned used intake manifolds when turning yours in as a core. You can scroll back in this thread to see how mine was plugged up at 270k. I had Elf over at Streamline Industries clean mine out. If you don't want to do it yourself, I recommend them highly.

 

[TRD270]

Good chance school is getting cancelled tomorrow.....damn plane maintenance. I'll pull the intake apart and have a look. FWIW my mechanic things it might be a clogged cat creating too much back pressure which is why its pooing out at the higher rpm, longer into the boost, which is why its not showing up in 1st and second

 

[Rot Box]

Also check the snow screen inside of the intake snorkel. A little tricky to find.. It’s near the rear of the battery next to the fender. They clog with leaves and such.

 

[Unimog]

Also check the snow screen inside of the intake snorkel. A little tricky to find.. It’s near the rear of the battery next to the fender. They clog with leaves and such.

This was really plugged up on mine, too, but the main problem was carbon in the intake runners. Some places had maybe half an inch hole left for air to go through. For what it is worth, I've owned the car since new (same year as yours). I don't know if it has a cat or not, but I've never done anything with the exhaust, just the intake.

 

[TRD270]

Also check the snow screen inside of the intake snorkel. A little tricky to find.. It’s near the rear of the battery next to the fender. They clog with leaves and such.

Mines a Golf, I think the air boxes are different. I didn't look to hard, but I believe my snorkel is just above my grill

 

[TRD270]

I've continued to dig around the interwebs, i'm now 98% sure its the intake. I found a few people with literally exactly what i'm experiencing who actually posted what fixed it. One poor sap had cleaned his intake.... just not deep inside. Replaced the cat, n75, fuel filter and some other things can't recall but it was pretty much everything. Only to pull the manifold again and dig deeper to find a 90% blockage in the bend. I'm going to hold off for a bit as my drive to school is almost all flat and is only annoying when trying to pass. If nothing else big pops up with the car i'll spend the money to get it fixed in a month or so.

 

[Rot Box]

I had to re-seal my injector pump recently. A drip in the driveway every once in awhile turned into a puddle every day after a few months time..

Kind of an intimidating job.. I was able to replace the major o-rings/seals though with some good instructions and parts from Diesel Geek. I had to buy VAG-Com/VCDS to recalibrate the fuel delivery. I have to say that software was well worth the money. I disarmed the weird/annoying door locks and changed my EGR values while I was in there. The car runs very-very well and so-so smooth. Money well spent imo.

That said my milage has dropped significantly in the last two years. 28 mile commute to less than 5 miles since I moved out of farmville might be the reason. Either way I feaking love this VW.

There has been a Malone dealer that popped up recently in my area. Strongly considering the dynamicERG/Idle upgrade/stage 1 tune. Money-money

 

[Greg]

I loved the Malone Dynamic EGR in my '06 TDI, and the Stage 1 tune made a 'fun' car quite sporty!

 

[TRD270]

I replaced the temp sensor in mine, still getting low temps. Tried the thermostat next that fixed the problem. Almost put a 1000 miles on the little bugger already. 42 mpg first tank, running 40 degrees below operating temp and discovered the rear tires were about 10psi low. Hoping for better mpg this tank. Still having the power issues, read some ways to test the MAF without the VCDS to eliminate that. Hopefully have some more time next week to tinker with that.

 

[TRD270]

So question for you all, I just replaced my headlights (whole new assembly) and went to move the car out of the garage. It fired for 1/2 a second then died..... now I have a crank no start.... WTF? I unplugged the headlights still nothing, no codes.


Edit, Also it smells like its getting fuel, and after a few seconds of cranking it seems to be really rough

 

[TRD270]

Got it to start, runs like crap has no power and is pouring out grey smoke, it sounds like the timing is fubar

 

[Greg]

That doesn't sound good, wonder if the timing belt jumped a tooth or something.

 

[TRD270]

That doesn't sound good, wonder if the timing belt jumped a tooth or something.

Exactly what we think happened, got it to mechanic he hooked up his scanner. I think the timing was supposed to be 77 degrees if I remember right. It's currently 255. Lucky it didn't jump any more and crush my valves

The guy I bought it from said it was replaced at 190k, its currently at 240k. I pulled the cover off and the outer half of the belt is chewed to shreds. I'm guess it was a low buck kit and they didn't replace the tensioner. I've been hearing an odd noise from that side but was thinking it was my accessory belt. I'm also wondering if it had previously jumped a tooth and was running decent and maybe related to my power issues mid band

Appears it just happens to be circumstantial to when I was doing the headlights, which is lucky because twice today I was 40 miles away from the house.

 

[TRD270]

On a side note to today's project, my headlights were so fogged over no useful light was being emitted. Polishing wasn't going to work because they were as coarse as 50 grit sandpaper. I considered buying replacement lenses but I was worried about breaking the housing while trying to pull them apart. After trolling TDI forums I came across vxtuning.com. I had considered putting projectors on, but they all had the stupid halo lights and were super expensive and none had very good reviews, the normal replacements I found on amazon had bad reviews and were still crappy plastic.

The vxtuning have glass lenses and were quite praised on the forums, I also happened to find the euro spec ones with the black bezel. The previous owner had already swapped the tail lights and marker lights to the euro spec dark so it was a win win. They seem quality and are actually glass, noticeably heavier than the stock ones. We'll see long term if they are sealed well. Also these were actually about $20 cheaper than the amazon ones, I think i'm the only one with a golf but they also have jetta headlights if anyone is looking

They come equipped with the fog lights that you couldn't get in the US as well, they do require replacing the harness and swapping out your headlight switch with a euro spec one.


Before



After

 

[Unimog]

Right after reading about your problem, my 02 TDI wouldn't start up the next morning. It felt like a jinx of some kind. I was shocked since this car has never left me stranded in 320,000 miles. Every time I would try, it would just fire a couple of times, then crank without firing. I finally tried a little ether and that made no difference! I figured out it had to be air since it wasn't fuel. After a little research, I found the anti-shudder valve was stuck shut. This valve just shuts off the air supply to make the engine stop quickly when you shut it down. Anyway, that valve was stuck shut. As soon as I knocked the valve open, it started right up!

 

[TRD270]

After a little research, I found the anti-shudder valve was stuck shut. This valve just shuts off the air supply to make the engine stop quickly when you shut it down. Anyway, that valve was stuck shut. As soon as I knocked the valve open, it started right up!

When mine wouldn't start after some googling that was also the first thing I checked....... I wasn't so lucky

 

[TRD270]

Missing a bit on the belt