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Discussion Starter #1
Sorry for the long post but I'm trying to give as much info about my problem. Have had the car (2002 1.8T wagon 5spd) since new. Been able to do all the maintenance myself thanks to the info on this forum but am stuck now. Actually considering having a mechanic looking at it (I know, the horror!).

Started close to a year ago, was stuck in a traffic jam on a very long, steep hill and it was very hot outside. Had to creep forward in 1st gear for a long time. Car suddenly started to smoke from the engine so I pulled over. Engine was running normal and no CEL. Smoke seemed to come from under the back of the engine/transmission area and I could not find the source. Did not smell like a burned clutch, burned motor oil, or coolant. Temp on the gauge did not move and coolant level stayed normal. Waited for traffic to clear and car to cool down a little and was able to drive without problems after that. The one thing I noticed afterwards was that the car took a little longer to start after it sat for a little. I had to crank for longer than normal and when the engine finally caught, it was running hesitantly at low rpm for a couple of seconds before running normally. Did some searches and figured something was wrong with the vacuum system and would look at it for 200k service.

Drove it for a couple of months and then, 200 miles before reaching the 200k, got coolant level warning on the freeway. Pulled over and coolant was pouring out from the front of the engine. Added some water and took the next exit to wait for a tow truck. Later at home found it to be a coolant pump failure (had done TB and pump 55k earlier). Pump was pretty much completely seized and tweaked but I'm positive engine timing was not impacted. Did the timing belt job and then checked the PCV system (had done it at about 100k). Replacing the check valves, vacuum suction pump, and checked all the hose connections. Cleaned inlet manifold and throttle body. Did not see anything wrong or broken. Still had the starting delay afterwards and still no error codes. Replaced CTS just to be sure (cheap and easy to do) but made no difference.

Have been driving it since and then recently checked the oil level after 2000 miles and found that I had to add two quarts. I never had to add oil before between oil changes (5k interval, always Mobil 1, initially 5w30 and last 100k 0w40). I have no leaks under the engine, coolant is clean and no change in coolant level (head gasket should be fine then), throttle body is still very clean and dry (assuming therefore that oil is not coming from turbo), so I took my plugs out last weekend. Most of them looked ok but the cylinder 4 plug had a lot of oil caked on (pictures of all 4 plugs in order and then plug 4).

Did compression test (pretty much cold engine) and got 1: 150, 2: 130 and after adding a little oil 150, 3: 140, and 4: 155. So the cylinder with the most oil had the best compression. I'm assuming because of the massive carbon deposits.

Then did leak test and got @45 psi, 1: 16%, 2: 22% (still probably had the oil from the compression test), 3: 22%, and 4: 52%. I cranked the engine a little and tried again on 4 and got 47%. Then added some oil and got 15%.

Looked at all four cylinders with a remote camera and did not see any wall damage but a lot of carbon deposits on top of piston 4.

Put it all back together and ran the engine while holding a piece of plastic instead of the oil fill cap and had decent suction at idle or higher rpms. So I don't think I have ever-pressure in the crankcase forcing the oil in the cylinder.

So to me it looks like I have some wear on my cylinder 4, possible due to overheating when I lost my coolant since the increased oil consumption seems to be recent. Is there anything else I should look at or should I just clean it up with some sea foam and try to switch to a high mileage Mobil 1 and see if it improves? Rest of the car is in great shape (except for some clear coat peeling) so would hate to have to trash it.
 

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with the coolant pouring out of the front of the engine there is the distinct possibility of the turbo being cooked and with 200k thats alotta turbo, just replaced mine (190K) and although turbo was working it had significant end play. I would check out the turbo ... and the oil , if indeed leaking from turbo might be on the exhaust side bearing, check the exhaust tailpipe by rubbing your finger around the inside of it, oily residue may point to the turbo.
 

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also check out the recirculation hard pipe coming from the turbo for residue or blockage, think it is above... but definately next to saip pump hard pipe, and the residual oil literally bakes in there from heat rising from the cat,turbo area.
 

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Hey chief, that is a great suggestion. I did check the exhaust pipe on the inside and had a ton of carbon on the inside wall and was surprised that that much would make it past the cat. It used to be really clean and light gray. Since I did not see significant oil in the inlet manifold, I thought the turbo was good. Still sounds good too but it still is the original after 200k so the loss of coolant may have been the end of it. Will check.
 

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Quick update on my car. Really did no know how to figure out what was going on with my engine so decided to take the head off. Cylinder walls looked good so had my head rebuild (valves and valve seats cleaned, new exhaust valve guides, and a used inlet cam (some of my lobes were definitely worn)). Also got a new OEM turbo while I had good access. Put it all back together and used M1 5W30 high mileage oil. Car runs good with smooth idle and decent power. Fuel consumption is a little higher than before (used to be low 30's but now is about 28 mpg). May be the thicker high mileage oil. Drove it for a couple of months and just passed 2500 miles since rebuild. Oil consumption about 1 quart per 1500 miles so not too bad. Just did compression check and looked at my spark plugs. Compression was decent with 140 psi in all 4 cylinders. Spark plugs for cylinders 1 - 3 looked great but still oil on spark plug for cylinder 4. So it looks like everything is great except for the oil control ring in cylinder 4. Would not be surprised if it is broken. I really don't think it would be worth it to look for a new engine as anything that would fit my car would be at least 15 years old. Anything I can do outside of a complete bottom end rebuild, which probably would not be worth the effort for my car? Is there a way to replace the ring on cylinder 4 without completely tearing my engine apart?

Just wondering if this is the end of the road or do I have other options...
 

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Always use

5W-40 or 0W-40 FULL SYNTHETIC OIL.

Preferably Liqui Moly, Pentosin or Motul but

Walmart has 5W-40 Castrol less than $30.



Sent from my iPhone using Tapatalk
 

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Is there a way to replace the ring on cylinder 4 without completely tearing my engine apart?

Just wondering if this is the end of the road or do I have other options...
You will have to pull the head again, and remove the oil pan to access the rod bolts.
 

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Discussion Starter #8
Nine months later and maybe hope for a new lease on life for my 2002 Passat Wagon 1.8T. Took the head off again and had it re-checked. They did not find anything wrong but then still replaced the exhaust valve seals to be sure. Since the head did not seem to be the source of the problem, decided to check the rings. Got an engine support bar from Harbor Freight and was able to lift the engine and transmission enough to remove the oil pan without loosening the subframe. Not having the PCV system and coolant flange between the engine and firewall gave me a lot more space to lift the engine.

With the pan off I was able to remove the rod lower bearing bolts and remove the pistons from the top. Did not find anything significant that could explain the oil consumption in cylinder 4. Measured cylinder diameter in six locations each and was within spec (not bad after 200k) and again did not see a big difference. Measured the ring gaps and they were also all within spec. The only thing I noticed that the oil ring in cylinder 4 was really plugged up with carbon deposits. So maybe that was preventing the evacuation of oil.

Used a flex hone to refinish the cylinder walls, got new piston rings and made sure the gaps were all good, got new rod lower bearings (showed some signs of wear), and new bolts. Cleaned the oil pump really well and checked it was still in spec. I had no signs of sludge at all and oil pump screen was still pretty clean. Finally put it all back together, hooked up an oil pressure gauge and made sure I had good oil pressure. Using a non-detergent oil for break in and just finished a 70 mile ride of a curvy road to make sure I varied the RPMs.

Took me a long time to do all this since I had several decision points and had to figure out was my next steps had to be. Plus then I had to find the right components and figure out how to do all this. On top of that got busy with work so then worried I forgot how to put it all back together. Ended up being easier than I feared.

Engine sounds good and car drives really well. No codes up to this point. Will change oil after 500 miles and then go back to normal 0W40 oil and start monitoring oil consumption and re-do leak-down test to see how everything settled.

Have been looking for another wagon and just can't find anything that compares in driving, space, and fuel consumption. So trying my best to get a couple more years out of it. Will give an update when I know more.
 

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Quick update. Drove the car for 625 miles and so far so good. Oil pressure was a little on the high side (66 psi at 3k rpm warm) but that may have been the oil I used for break-in. Felt a little thick even though it was straight W30. Engine is running smooth, power is good, and only one code related to the CCT timing. Had that one previously sometimes and may also be related to thicker oil, especially when cold. Checked spark plugs and cylinder 4 is definitely cleaner (replaced it with a brand new one this time). Did leak test and got consistent 15 - 20% on all four when warm.Went back to Mobil 1 0W40 and will take it on a road trip to Sedona (1k-mile trip) so will get a good idea about the oil consumption and see if it improved. Keeping my fingers crossed to see if I saved it from the junk yard for a little longer.
 
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