B4 intake manifold cleaning (photos!)

lupin..the..3rd

Veteran Member
Joined
Feb 7, 2004
Location
USA
TDI
Passat B4 1996
Ok, so I was bored today and decided to clean my intake manifold. My TDI has 93k miles on it.

My B4 lays a pretty nice smoke screen (spy hunter style) at WOT.

It also felt very sluggish above 2600 rpm. It had gobs and gobs of torque at about 2000 rpm though (due in part to a stage three rocketchip).

Also, my milage has been about 44 mpg. And this is doing 100% highway miles, quality fuel, and healthy dose of powerservice. All my filters are new and snowscreen is clean.

The smoke @ WOT, lethargic acceleration above 2600 rpm, and "low" highway milage all pointed towards a clogged intake manifold.

1Z engine sans intake manifold:



Nasty:





Taking a bath in some B100 Biodiesel:



Should breathe a little better now:



The six allen bolts were a moderate pain in the arse to get in and out. It would have been much easier if these were 10mm "regular" bolts.

I used a high-tech special manifold cleaning tool (flat blade screwdriver) and a tub of B100 to do the job. Using the screwdriver alone, I scraped enough crud out to fill a pint glass.
After that I let it soak in the B100 for a while, agitating it regularly. Once it was clean, I rinsed it well using hot water, and dried it thoroughly with a hair dryer. Wear gloves, because the biodiesel/soot/oil makes a foul combination and is fairly disgusting.

Once I had everything all back together again (or so I though), I went for a test drive. I have a vdo boost gauge installed, and at 4 psi, the engine gave a loud high-pitched psssssss! noise. And it wouldn't go above 4 psi. After an hour and a half of cursing and grumbling and poking around, I discovered one of the intake runner hose clamps had failed to find it's way back on. Oops.
So I put it on and everything was good.

Conclusion: WOW! I had no idea these TDI's even had a "top end"!! Before, there was no power above 2600 rpm. Now it pulls like a train to 4000. It's like getting "chipped" all over again!! I'll be interested to see what my highway milage is like now. I'll post a followup once I've had a chance to go through a tank.

If you have 80k miles or more on your TDI and you haven't done this yet, I would consider it a required maintenance item for you to do.
 

dubburke

Veteran Member
Joined
Feb 24, 2004
Location
N.Ireland
TDI
seat toledo tdi 1996 white
GOOD JOB. How long did it take you?, i take it i shouldnt try it as i have no mechanic skills to talk of though, wish i had!
 

lupin..the..3rd

Veteran Member
Joined
Feb 7, 2004
Location
USA
TDI
Passat B4 1996
Thanks dub
, it took me about four hours from start to finish. This is the first time I've done this, and I don't have a Bentley manual. Was pretty straight forward though.
 

dubburke

Veteran Member
Joined
Feb 24, 2004
Location
N.Ireland
TDI
seat toledo tdi 1996 white
Didnt see the process on video as i cant seem to get it to work, not very good with computers!
 

dubburke

Veteran Member
Joined
Feb 24, 2004
Location
N.Ireland
TDI
seat toledo tdi 1996 white
thanks for the help, only problem is we dont have broadband yet so it would take a week to download!, we are a bit behind the times in ireland!!!
 
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