2004 Passat TDI new "thudding" noise

bonesmtb2

Member
Joined
Feb 7, 2010
Location
Troy, NY
TDI
2004 Passat TDI
So my wife's 2004 Passat TDI has a new, possibly very bad noise.
It sounds like a "thudding", that is loudest near the air filter. I opened up the airbox, and it is definitely pretty loud coming out of the air intake pipe. Sounds like you are hearing the engine firing. The car also seems very underpowered, and is blowing more black smoke than usual.
My thoughts so far are head gasket, intake valve stuck open, or possibly a faulty injector. Anyone ever experienced this before?

After doing some research online it seemed like the EGR could be at fault. I took the intake all apart and cleaned a ton of carbon out of there. Reassembled with new gaskets, but the issue is still there. I really thought that was going to fix it :(

This is what the EGR valve looked like


This is the carbon that was pulled out of the intake


This is what the intake ports looked like
 
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aja8888

Top Post Dawg
Joined
Dec 25, 2007
Location
Texas..RETIRED 12/31/17
TDI
Out of TDI's
Intake valve stuck open would be curtains for the valve as the piston slammed into it. I'll go with bad cam or a busted follower or both.
 

bonesmtb2

Member
Joined
Feb 7, 2010
Location
Troy, NY
TDI
2004 Passat TDI
Thanks for the replies everyone! Camshaft makes sense, but not exactly what I want to hear. I'll probably take it somewhere to get a quote today, since I know you need special tools to set the timing etc.

Might be looking for a new car instead, ugh, as I don't think the car is worth putting that much money into.

I guess I could just take off the valve cover and take a peek, to see if the wear is apparent.
 
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bonesmtb2

Member
Joined
Feb 7, 2010
Location
Troy, NY
TDI
2004 Passat TDI
The car has 255000 miles on it. I was really trying to get it to 300000 miles haha, plus my wife loves the car.
 

Smokerr

Veteran Member
Joined
Sep 3, 2005
Location
Alaska
TDI
Passat Wagon GL,2005,Silver
Mine as well, good luck

It should not be blowing any black smoke ever. If it is, or light smoke, a diesel additive might clean that up.

It did on ours. I think the DOC got hurt with Alaska high sulfur diesel before the shift (our was 500 ppm at the time due to a waiver)
 

zzdiesel

Veteran Member
Joined
Dec 10, 2010
Location
sask. mostly now Wa.
TDI
05 passat tdi Geared BSM and Bewcam 2nd 2005 deleted ,converted and bew cam stage 2 Malone3 tune.
Camshaft kit is around 500 with cam, followers, bearings, and bolts, and a complete timing belt kit is under 200. So, 700 plus labor, maybe 4 or 5 hours for someone, not me, who knows what they are doing. So, how much does your wife love the car?
 

woodyboyd

Member
Joined
Feb 17, 2015
Location
America's Heartland
TDI
'04 Passat Wgn
Passat B5.5 TDi PD Throaty Nose

Mine went instantaneously; car was performing up to established expectations and then suddenly a profound thump propagated from under the hood. Got out of the car and it sounded like the intake had a gaping tracheotomy; a periodic and deep hollow sound emanating from the head near the intake or exhaust (but not the loud banging of an open-header).

Heard and read reports of cam lobes flattening and lifters/followers going bad, but this took the cake. Would have anticipated some gradual degradation; i.e., incremental yet noticeable loss of power and downward spiral of FE, but that didn't happen. One moment I could milk it for 43 to 46 mpg, the next it was straining to achieve 38 to 40 with power and acceleration very perceptively diminished.

My just rewards for a slavish devotion to 505.01 motor oil (Motul or Liqui Moly). Unfortunately I'm the 2nd owner. Got car with 175k on the clock. Can only trust PO used the best. Car just passed 260k, with body and interior that hardly reflects its age and use.

Spent the day researching my options; could go with an economy package--camshaft kits from $300 to $500--or the TDiphile's-robust preference (Franko6). The more affordable options don't always specify their manufacturer. Franko6 starts with and seriously hardens industry-accepted and OEM-supplied Febi products (namely the cam). Improvements extend to journal caps, reuseable bearing bolts and nitrified lifters/followers, all of which have known VW-design weaknesses.

This is not a paid endorsement, but Franko6 supplies a camshaft kit beginning at ~$550 for the BHW. For the adventurous, Franko6 also has BEW (1.9L TDi PD) versions (greater vehicle lifecycle exposure) that are adaptable with slight mods and reputedly more reliable. Among Frank06's offerings is a Stage 2 BEW compatible camshaft, of course that runs more than 2x their BHW model, while facilitating an upwardly compatible path for deeper tuning mods.

The lower-half of my engine is solid; very little oil consumption, clean, oil-free intake (no blow-by). Had BSM deleted with ALH oil pump upgrade when TB & WP service was performed at point-of-purchase. Although repairing the cam with a Frank06 kit and another TB & WP kit will likely run between $1300 to $2000 (parts and labor), can't see why I'd opt out and shop for another B5.5 TDi PD. Trying to find a low-mileage (<100kmi) B5.5 TDi or a good running one (<200kmi) from $3K to $7K, that still would likely have the BSM, need the TP & WP service, and need a new cam--who knows when--doesn't add up.

I'll stick with my current Passat B5.5 TDi, repair & upgrade the cam, and rely on the lower-half of the engine to pull the car through 500kmi, hopefully without any further major motor repair. When the GMR, auto trans, dies an FHN Euro-Diesel 5sp MT conversion awaits.
 
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