It happened twice today.
And I am SURE to know how to get it working (get it start up from this situation).

Bascially this is what I did.
I have to crank it. then after it is cranking (it won't start) I have to step INTO the gas pedal ALL THE WAY. I DO MEAN all the way otherwise won't do it. then as soon as I step the gas pedal all the way in, the car sound different, and after like 2 second, it starts up. RPM shoots high, I let go of the gas, and RPM stay SOLID on 1200 RPM (coz cold start) then drop back to ~700RPM solid.

So odd, only at start up.
And also answer some of other question. when I do that, the car starts up, but a HUGE black smoke from the rear. seems like running super rich.

OK, it seems like, under certain condition, at startup, it won't give gas, so the engine won't start up, but when I WOT it at cranking time, it will have WAY TOO many gas to start so in result black smoke for like 2-4 second after car starts.

This problem won't happen after I shut off the car, ONLY when I leave the car there after driving for like 2+ hrs.

Any better ideas now guys?
Gil

 

maybe a cold start sensor?

 

Now,My wife's 2001 A6 avant is doing this and I am going to replace the sensor in that. I thinks the sensor is failing in a certain temperature range (coolant) and is defaulting to an overheat reading which is telling the ECU not to let the engine start. This is why it is happening when you let the car set for two hours or so. The black smoke is because there is unspent fuel in the cylinders when you finally get it to crank. Let me know if you found a different fix. The sensor is like $15 at the dealer.

 

Probably the engine lost compression, like it happened to me. I would say that the previous owner was not making miles or always driving on low rpm, and because of low temperatures the fuel does not burn neatly thereby leaving smoke dust to compile at the base of the valves making them not to shut tight when engine is turned off.
Now ur engine keeps air tight in order to reserve air for initial combustion once the starter cranks the engine, but because the non air tight valves lets the reserved air to escape the engine loses compression and cannot start.
SOLUTION LIKE I DID ON MY '98 QUATTRO.
Open the oil fill cover on cylinder bank 2(driver side).
Open valve cover on cylinder bank 1.
Ensure ur battery is on full charge.
Start and hold the gas pedal 15seconds,...Stop.
Try again if it doesn't start on one try. Mine started on the 3rd try.
Once it starts, maintain 2000rpm while someone helps u in fitting the valve cover temporarily cos you have to use RTV to fit it properly later.
This process lets the valve suck enough air to blow off the smoke dust, gunk and sludge covering the base of the valves.
If this works then ur cars is good to go. Check spark plugs to see if they are due for change.
Clean air filter, clean MAF with Electronic cleaning spray,
Check breather hoses for sludge.
Clean throttle body of oil and dirt sludge.
Take it for a long drive at 3000 or more rpm.
Enjoy ur quattro, its quattro or no audi.
Mine still drive smoothly at 265000miles.

Reakmexy - Nigeria.

 

You're replying to a post from 2005.

 

well ya never know . maybe the guy is still waiting for a response after 11 years..

 

he may have inherited a large fortune from a member of the royal family and is in need of help distributing it.

 

I also have a 2013 passat but am not discarding my 1st love for Volkswagen.
1998 audi A6 2.8 ATQ, owned for 8years and counting.