'97 Passat TDi-Need advice!

Yesterday,I bought a '97 Passat TDI with 224K on the odometer for the princely sum of $3250.00. At that price,I figured that I should jump on that deal and so I did.The car started up immediately,and ran strong.(Some black smoke on brisk acceleration though)The next morning I started the car with the engine cold and the engine leaves a fairly dissappointing cloud of smoke billowing out of the pipes for a minute,or two.The idle sounds a bit rough during this time.It looks like the previous owner warmed the car up in advance of my test drive as these symptoms were totally absent yesterday. :0( I removed the air filter(which looked a bit dirty,but not filthy) and also unscrewed/removed the circular fine mesh screen beneath the air filter.It was heavily clogged with insects,dirt,and soot.I thought to myself: AHA! Well,the black smoke that I was seeing is gone,but the car is still smoky upon startup(the temperture was in the mid 60's here yesterday)(the car starts immediately even when cold) When the engine is up to full operating temperture,I can't see anything in terms of obvious visual tailpipe emissions.I also can't really tell for sure if I'm seeing white,or blue smoke.I still haven't driven the car enough to know what is happening with the fuel economy. I found something a little bit weird: The black circular device on top of the 'valve cover' has two hoses coming out of it.The hose on the left is open and simply drains (?) out the bottom of the vehicle.Does anyone have any insight on the purpose of this cob job? Did I get hosed,or are there procedures that I can follow through with to give me a better picture of what is going on? I'm hoping it's something like an air,or an injector timing problem,or something to do with the fuel injectors.I'm keeping my fingers crossed. I would greatly appreciate any feedback.Thanks very much!

Reply to
Nevermind
Loading thread data ...

Take it to a good dealer and have them do a quality check on it. You will soon know if you got reamed...

Reply to
Peter Parker

A couple of things come to mind:

1) If it's bluish smoke it could be one or more of the glow plugs is bad, which might explain the rough idle, too. 2) Some oil-heads like to get more power by installing different computer chips and larger injectors. I don't know if this is possible in the '97 models, but this kind of mod can increase smoke.

Check

formatting link
for *much* better info on VW diesels.

Reply to
Wake

If the smoke is more blue than black its more likely to be a bad valve seal than a glow plug. If its black to white then its for sure a bad glow plug...

If it starts easily compression is ok which means the problem is not mayor.

Reply to
Eduardo K.

Thanks for the correction. I've had glow plug problems that resulted in smoke, but I must not have remembered the color correctly.

Either way, I don't think the OP has a junker on his hands, even with 200+k.

Reply to
Wake

I would go to tdiclub.com and ask for advice on a good area TDI mechanic. Do you know if the timing belt had been changed at the proper interval? If not you MUST have it done as these engines are interference engines.

On that era of car many times the MAF (mass airflow) sensor has gone bad. a good source of parts is either tdiparts.com or worldimpex.com

Make sure you run either power service and or stanadyne in your tank.

Last but not least, use a proper motor oil for your engine. Do not use dino oil, use only a semi-synthetic or a full synthetic that says meets the diesel spec of your motor.

gck

Neverm> Yesterday,I bought a '97 Passat TDI with 224K on the odometer for the

Reply to
Gary Klein

Reply to
Nevermind

I wouldn't say that -- if you've got a dead glow plug, then at start-up you will get white smoke, which isn't really smoke, it's atomized raw fuel coming out the tailpipe unburned. If it's only one glow plug, you can even see individual puffs of white smoke coming out the tailpipe, from the single cylinder. It'll go away as the engine warms and the cylinder starts to fire.

If the smoke stays white after it's fully warmed up, then you'd have to suspect the famous VW valve-guide seals.

Any time you have glow-plug issues, make sure you check the fuse first. I don't know about the newer VWs, but the older ones had a fusible link mounted at the top of the firewall.

Reply to
Brian Running

The hoses your talking about are to allow the engine to vent into the air instead of back into the engine. On your vintage passat (I had a 96 passat tdi wagon) the oil fumes from the crankcase will turn to oil and build up inside the intercooler. On newer ones that have ERG the fumes mix with the soot in the exhaust gas and cake up the intake manifold in as little as 50k miles the intake can be half closed off.

JoBo

Reply to
Jo Bo

You can't tell from an internet article but a very rough guess is that it needs a head job. Weakest part of a VW diesel engine mechanically imho, is the head (including head gasket). Perhaps valve guides and seals. Valves ground and seated are needed.

Even on gas engines. The head I have on a bubble block right now I simply reconditioned not rebuilt since the guides were good. There was about 1/8 inch carbon plated on the back side of each valve (under 200K mile Digifant head) and in the ports. Being careful not to damage mating surfaces I completely blasted (sand blasted) to the bare metal including each back side of the valve.

Lot can go wrong with a head with high mileage and carbon buildup though

229K for diesel is not high - the head may need service IF not serviced previously.

Harry

Reply to
Harry

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.