Before you come in here to say "BRM engines NEVER get clogged with gunk", stop. I've read all the other threads that a search could find and they were filled with "because of ULSD, gunk doesn't exist" or things like that.
That's why I'm here.... because I haven't found the solution to my problem.
Please don't tell me that it never happens because it obviously happens. Maybe they're not supposed to clog up like it seems mk4's were designed to do, but mine is gunky. I'd like to ask for some help to diagnose what's causing it.
Proof:
This is my 2006 BRM 5spd. I work on it all myself and took this photo myself on my cell phone. It's never used off-road fuel and for as long as I've owned it, it's only been on B5-B20 ULSD since that's what's available where I live. I also make sure to choose a good quality fuel station, even if it isn't the cheapest. I also use Power Service Diesel Kleen just about every tank. I'm confident it's not "bad fuel".
A brief history of this engine.
~110,000 miles: Bought car. Began using Schaeffer Supreme 9000 5w40 oil right away after hearing about camshaft problems.
~130,000: Replaced noisy DMF for SMF. Saw a very clean engine bay on backside. No leaks, nothing.
*Fuel economy around 45 mpg avg. (manual calculation)*
Noticed some black tail pipe smoke and a very quiet hissing that I mistook for a normal noise.
~145,000: Replaced camshaft (minor sharp edges, not severe).
*Fuel economy drops to 41-43 mpg. Entire intake system is very clean during camshaft change. Tried messing with Torsion value to get some mpg back. The more negative, the better the mpg but also more smoke. Settled at 0.5kw for no smoke and just dealt with being lucky to get 43mpg.*
~172,000 miles: Check engine light on for Emissions Workshop, two glow plugs tested bad and getting a code for something like "running rich". Can't remember the exact code. Tail pipe smoke has been getting worse. Fuel economy had been steadily getting worse. Can't even hit 40mpg any more while driving calmly, like always. Actually getting some 35mpg tanks. Investigation finds clogged intake (first picture).
-Removed intake manifold and cleaned it of all gunk. Cleaned EGR and ASV area. Some gunk on it, but not enough to block movement. Verified ASV works properly according to VCDS.
-Could not get all the gunk out of the intake runners. Didn't want to push it down onto the valve, but I did try my best.
-Also noticed driver side e-brake cable had been sticking and causing dragging. Fixed that at same time. Fuel economy only improved slightly; hovering around 40. Still smoking at startup and at high pedal input or 2000+ rpm.
-Replaced MAF and O2 sensor: no change.
-Noticed dry black soot all over back of engine bay from behind the EGR valve. Hissing noise has very gradually gotten a little louder, but not obnoxious.
-Replaced EGR assembly.
~185,000: Changed timing belt - noticed fuel economy improvement from upper 30s back to 43ish. Torsion value was at -2.0kW. Check engine light comes back on; Emissions workshop + another bad glow plug. Black smoke is pretty bad. Changed torsion value to -1.0kW. Smoke is still bad, CEL is still on. MPG is still 40+, but too soon to know a good average. Was able to get 50mpg on a long trip driving 70, but that's the only time that happens.
Now we're all caught up to today. The intake manifold has become clogged up again. Can't get 45 mpg when driving like I should be touching 50. It's not yet as bad as in that photo, but it's maybe a quarter of the way there and sticky and gooey as hell.
Final notes:
Oil changes happen every 10k miles. Still using Schaeffer 5w40 Fuel filter changes happen every 20k miles and is currently only 11,000 miles old. I'm on my 3rd? air filter since owning the car. That reminds me, the hot air flap in the lower air box seems to be always open because of a spring pulling it open. Previous VWs I've had, the hot air flap had a weak spring pushing it shut. Is this how these air boxes are supposed to work?
Summary:
-Bought clean engine
-Started using 5w40
-Changed camshaft: worse f.e.
-F.E. gets even worse, CEL comes on, intake is gunky
-Cleaned intake, replace parking brake cable, change O2 sensor/MAF/EGR
-Change timing belt, intake gunky again, plenty of exhaust smoke
That's why I'm here.... because I haven't found the solution to my problem.
Please don't tell me that it never happens because it obviously happens. Maybe they're not supposed to clog up like it seems mk4's were designed to do, but mine is gunky. I'd like to ask for some help to diagnose what's causing it.
Proof:
This is my 2006 BRM 5spd. I work on it all myself and took this photo myself on my cell phone. It's never used off-road fuel and for as long as I've owned it, it's only been on B5-B20 ULSD since that's what's available where I live. I also make sure to choose a good quality fuel station, even if it isn't the cheapest. I also use Power Service Diesel Kleen just about every tank. I'm confident it's not "bad fuel".
A brief history of this engine.
~110,000 miles: Bought car. Began using Schaeffer Supreme 9000 5w40 oil right away after hearing about camshaft problems.
~130,000: Replaced noisy DMF for SMF. Saw a very clean engine bay on backside. No leaks, nothing.
*Fuel economy around 45 mpg avg. (manual calculation)*
Noticed some black tail pipe smoke and a very quiet hissing that I mistook for a normal noise.
~145,000: Replaced camshaft (minor sharp edges, not severe).
*Fuel economy drops to 41-43 mpg. Entire intake system is very clean during camshaft change. Tried messing with Torsion value to get some mpg back. The more negative, the better the mpg but also more smoke. Settled at 0.5kw for no smoke and just dealt with being lucky to get 43mpg.*
~172,000 miles: Check engine light on for Emissions Workshop, two glow plugs tested bad and getting a code for something like "running rich". Can't remember the exact code. Tail pipe smoke has been getting worse. Fuel economy had been steadily getting worse. Can't even hit 40mpg any more while driving calmly, like always. Actually getting some 35mpg tanks. Investigation finds clogged intake (first picture).
-Removed intake manifold and cleaned it of all gunk. Cleaned EGR and ASV area. Some gunk on it, but not enough to block movement. Verified ASV works properly according to VCDS.
-Could not get all the gunk out of the intake runners. Didn't want to push it down onto the valve, but I did try my best.
-Also noticed driver side e-brake cable had been sticking and causing dragging. Fixed that at same time. Fuel economy only improved slightly; hovering around 40. Still smoking at startup and at high pedal input or 2000+ rpm.
-Replaced MAF and O2 sensor: no change.
-Noticed dry black soot all over back of engine bay from behind the EGR valve. Hissing noise has very gradually gotten a little louder, but not obnoxious.
-Replaced EGR assembly.
~185,000: Changed timing belt - noticed fuel economy improvement from upper 30s back to 43ish. Torsion value was at -2.0kW. Check engine light comes back on; Emissions workshop + another bad glow plug. Black smoke is pretty bad. Changed torsion value to -1.0kW. Smoke is still bad, CEL is still on. MPG is still 40+, but too soon to know a good average. Was able to get 50mpg on a long trip driving 70, but that's the only time that happens.
Now we're all caught up to today. The intake manifold has become clogged up again. Can't get 45 mpg when driving like I should be touching 50. It's not yet as bad as in that photo, but it's maybe a quarter of the way there and sticky and gooey as hell.
Final notes:
Oil changes happen every 10k miles. Still using Schaeffer 5w40 Fuel filter changes happen every 20k miles and is currently only 11,000 miles old. I'm on my 3rd? air filter since owning the car. That reminds me, the hot air flap in the lower air box seems to be always open because of a spring pulling it open. Previous VWs I've had, the hot air flap had a weak spring pushing it shut. Is this how these air boxes are supposed to work?
Summary:
-Bought clean engine
-Started using 5w40
-Changed camshaft: worse f.e.
-F.E. gets even worse, CEL comes on, intake is gunky
-Cleaned intake, replace parking brake cable, change O2 sensor/MAF/EGR
-Change timing belt, intake gunky again, plenty of exhaust smoke
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