boggs after coming to a stop during first 10 min after cold start

[tommiman]

I just got my '98 TSI AWD 2 weeks ago. During the first 10 minutes after a cold start when after coming to a stop the engine goes down to 200 RPM for about 3 - 5 seconds and then recovers. When it's at 200 RPM I hear a rotating squeaking/ratting sound coming the engine compartment on the passengers since. Any ideas?

 

[Rick4g63]

Tommi, list all your mod

The components that would make any "noise" coming from the passenger that would aid in the stalling of the car:

- loose lower i/c pipe or clamp.

- loose stock bov

- Remote case: the cruise control solenoid.

 

[tommiman]

no mods... just a K&N air filter

I had a closer look at my RPM gauge. Looks like I misread it. I thought it starts at 0 but actaully it starts at 500. This means that my car bogs down to about 600 RPM not 200 RPM like I stated before.

 

[tommiman]

... another things to add...

the car never stalled... it just bogs for 3 - 5 seconds

 

[Rick4g63]

Tommi when was a full tune up performed?

-The BISS should be replaced if car if 5 years or older.
http://www.machv.com/newbasidsets.html

- "bogging" is usually an indication of excessive fuel, wastegate failed (closed shut) and ignition misfiring.

 

[tommiman]

Why would it only happen in the first 10 - 15 minutes after cold start up? After that it idles fine. There is always a little surge though but it stays almost steady at 750 RPM.

Since I got it 2 weeks ago I've done the following:

K&N air filter
oil (Valvoline Max Life)
oil filter (Napa Gold)
transaxle and transfer case fluid (Mopar Synthetic)
differential fluid (Mopar)
spark plugs (Champion)
Fuel Injector treatment
timing belt (Mopar)
PCV valve
fuel filter
cooling system flush and fill (Prestone)
cleaned the lifters... no more ticking!

I'm thinking it might be a vacuum leak but don't know how to pinpoint it.

 

[tommiman]

I found that my BISS cap was missing. I put a wad of white grease over the screw and that seems to have solved the problem.

 

[luv2rallye]

Why would it only happen in the first 10 - 15 minutes after cold start up? After that it idles fine.

Perhaps coolant sensor that goes to the ECU (not the gauge one) is dead.

 

[tommiman]

It's back again. Looks like the BISS wasn't faulty.