Using my 99 V6 passat after sitting for almost 2 years, what should i check and change

[cmontboober]

Long story short, our passat has sat in the driveway for almost 2 years now since it was believed that the transmission solenoids had failed. I starting thinking about working on it for fun and found out that flooding is a common problem due to the sunroof drain and water damaging the tcm and ccm.

I pulled out the tcm, found water damage, and cleaned with electronic parts cleaner and it works again.

been driving it for about a week, but have a couple issues;

-p0455 large vacuum leak detected, I'm thinking the gasket between the throttle body and intake

-tires are flat spotted from sitting for so long.

any other recommendations on things to check after sitting for so long?

thanks.

[koidragon1980]

full tune-up... fluid changes (oil, tranny, coolant, brakes), new plugs, check/replace all belts for dry-rot/cracks (if timing belt goes, your engine is toast), new gaskets (valve cover, cct, cam caps... they might be ok, but will probably begin to fail soon and give you that common burning oil smell coming through the vents).

2 years is a while to sit, so all of the above should give it some fresh blood, fresh spark and good seals.

i'd put the timing belt/water pump job towards the top of the list. it's not cheap but it's not something you want to gamble with either. if you can handle doing it yourself, then you'll save a ton of $ on labor. order a kit from blauparts. while that work is being done, it's usually the best time to do the other gaskets i mentioned and a coolant flush.

also, since you had water damage, you should check all the possible ingress areas to make sure it doesn't happen again. aside from sunroof drains, check the seal around the fan behind the cabin air filter and the drain underneath the battery. the seal around the fan will usually cause leaks on into the passenger side and the drain under the battery will cause leaks on the driver side (ccm) if it gets clogged.

[cmontboober]

full tune-up... fluid changes (oil, tranny, coolant, brakes), new plugs, check/replace all belts for dry-rot/cracks (if timing belt goes, your engine is toast), new gaskets (valve cover, cct, cam caps... they might be ok, but will probably begin to fail soon and give you that common burning oil smell coming through the vents).

2 years is a while to sit, so all of the above should give it some fresh blood, fresh spark and good seals.

i'd put the timing belt/water pump job towards the top of the list. it's not cheap but it's not something you want to gamble with either. if you can handle doing it yourself, then you'll save a ton of $ on labor. order a kit from blauparts. while that work is being done, it's usually the best time to do the other gaskets i mentioned and a coolant flush.

also, since you had water damage, you should check all the possible ingress areas to make sure it doesn't happen again. aside from sunroof drains, check the seal around the fan behind the cabin air filter and the drain underneath the battery. the seal around the fan will usually cause leaks on into the passenger side and the drain under the battery will cause leaks on the driver side (ccm) if it gets clogged.

Thanks for the thorough response, the timing belt and other belts had just been done along with a new radiator install right before it went into the coma. I did a visual on the TB and it still looks good. Can you explain the burning oil.smell through the vents cause that's definitely an issue along with one of the valve covers leaking oil.

What spark plugs would you recommended?

[koidragon1980]

Thanks for the thorough response, the timing belt and other belts had just been done along with a new radiator install right before it went into the coma. I did a visual on the TB and it still looks good. Can you explain the burning oil.smell through the vents cause that's definitely an issue along with one of the valve covers leaking oil.

What spark plugs would you recommended?

your valve cover gaskets are likely the source of the burning oil smell. as the oil leaks from those gaskets, it will drip onto the hot exhaust manifold and cause a bit of smoke and burnt oil smells to get sucked into the cabin via the cabin air filter and fan. you'll notice that if you set the a/c or fan to recirculate the cabin air, the smell doesn't make it into the cabin from the engine bay.

you'll need to replace the valve cover gaskets, but check the cam chain tensioner gaskets also. if you're lucky they are ok. if not, then they are cheap but a pain in the ass to replace. order a new set of cam caps too. these are cheap and very easy to do... just pry out the old caps (found at the back of the engine on each side), then coat the new caps with gasket sealant and push them into place. let the sealant cure for 24 hours before starting the engine or you might blow the sealant and be stuck with new cam caps that are leaking oil just like the old ones.

i'd recommend ngk plugs. type is a little less important, but personally i prefer the iridiums... part no. BKR6IEX, stock no. 6418.

some guys use bosch plugs without issues, but i believe oem is ngk and our engines seem to like ngk best.

[cmontboober]

thanks man, are the chain tensioners similar to the type and install of the tensioners in the 1.8t's? I have a b5 A4 that I do a lot of work on but havent done much on the v6 since it's been sitting for a while and was always taken to a friend since my sister was driving it at the time.

[koidragon1980]

thanks man, are the chain tensioners similar to the type and install of the tensioners in the 1.8t's? I have a b5 A4 that I do a lot of work on but havent done much on the v6 since it's been sitting for a while and was always taken to a friend since my sister was driving it at the time.

i believe they are the same... but i'm not as familiar with 1.8t parts, so don't hold me to that. should be very similar parts and install, it's just that the v6 has 2 (1 at the back of the passenger valve cover, 1 at the front of the driver valve cover).

[cmontboober]

Just wanted to update the situation, I changed the spark plugs and it made a huge difference. I took it into the dealership for a recall on the heat shield and they replaced both sides for free.

As for the p0455 Large Evap Leak, after reading a lot about other people with similar problems I determined that it had to be toward the rear of the car since I could smell fumes after a drive when standing at the gas door.

Here are the steps I took to find it:

- Removed the gas door to look into that area, I read that one guy had a similar problem and it turned out to be a white plastic valve attaching 3 hoses in the tank filler area. I hooked up my vag-com and using rosstech software I ran the idle test for measuring block 071; started the car, selected the engine module, selected measuring block 071 and clicked go, then in the bottom left corner of the window i clicked basic measuring (or basic mode, something like that) and the window switches to only a single measuring block. the far right green text says its running a test after a few seconds and then the one to the left of that says its testing the system after that. when this one starts you can hear a pumping sound coming from the rear of the car, somewhere near the tank or near the tire area. while this test is pressurizing the evap system in the fuel tank I started sniffing around for the smell of fumes. I opened the circle cover in the trunk under the carpet near the passenger side backseat to expose the fuel pump and noticed a little discoloration on the top. I bought the fuel pump gasket from the dealership ($11, but found it online for around $4 but didnt want to wait for shipping) and followed a diy i found online for replacing the pump except i only replaced the gasket. it mentions in the diy that the hardest part is getting the gasket seated correctly and i admit that is accurate. there is a little lip around the whole thing which makes it difficult to get it all in there evenly as it should be. my approach was to back side in first so i could use my fingers to push the front where it would bunch up and it takes a decent amount of force to push it down completely. also be careful when removing the fuel lines they are still under pressure and a good amount of fuel will spray out. i put an old shirt over the lines when i pulled them off to not spray everywhere or into my eyes. and zip tied them back when i was done. I removed the fuel pump fuse before i started and ran the car until it died to take out as much fuel as possible from the lines.

The Large evap leak has been gone ever since.