1.8T feels sluggish and is now stalling

[markacino]

Hi all

Ive had my 2002 A4 B6 1.8t (non quattro) for about a year. When I got it, I had an issue with oil pressure due to a clogged up sump. I had that rectified and all was good.

I have noticed the car running a bit sluggish the last few months. Slightly rough idle (nothing crazy), some hesitation when giving it gas from a stop etc. It hasn't been a problem to drive. .

Last couple of days, when coming to a stop, the car has idled to zero and conked out. It has done this to me twice now in the last couple of days. Luckily the second time was as I pulled into my driveway.

So far on both occasions, the car has started straight back up, but did have the battery and ESP lights on. I restarted the engine and both turned off and I drove away fine.

I Decided to get a cheap code tester and it threw out quite a few codes at me. They are as follows

18017 - Crash Shut Down Activated
17887 - Brake Boost Vacuum System - Mechanical Failure
17544 - Fuel Trim: Bank 1 (System too Lean)
17953 - Throttle Valve Controller: Malfunction
16891 - Idle Control System RPM - Higher than expected
16706 - Engine Speed Sensor - No signal

I found the explanations for the codes somewhere online.

Any help greatly appreciated. Please keep in mind i have NO F'ING IDEA about any of this.

Cheers all :)

[ozMatt]

Hi Mark,

Another Melbournite - nice :)

First thing to check would be a vacuum leak, check out this thread for a lot of great info to get you started: http://www.audizine.com/forum/showth...-by-a4darkness

Start with that, as you may be able to solve the problems if you have some busted bits.

Cheers, matt

EDIT: Checked out that first code as I've never seen it - see description here: http://wiki.ross-tech.com/wiki/index...7/P1609/005641
If you haven't been in an accident you may have a fault/loose connection with one of the crash sensors (maybe something was knocked when you had the sump done?)

[markacino]

Have done my best to check the car over for some kind of vacuum leak to no avail.

Whats my next most likely culprit?

Given this code - 16706 - Engine Speed Sensor - No signal. Should I try replacing this next? I have had a look on eBay here in Aus, the closest thing I could find that MAY be the thing I am after is this:

http://www.ebay.com.au/itm/Meat-Dori...4AAOSw-itXsAgm

Is that the correct part???

Cheers all.

[old guy]

Clicky click®

Speed Sensor: P/N 078-906-433-A

EDIT: Added correct pic. (Thanks 5ktg!)

[markacino]

Is it the same thing as a crank shaft position sensor? Because that's what comes up for me when I look for that OEM part number.

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[5ktq]

Sure is.

except the one in OG's post has the wrong connector on it! The ones on B6 have FEP? style connector instead of junior timer.

like so:



I think that this photo is probably for transverse though, our cable is longer. Or have I got that backwards. OG's PN is correct though, just use that..

[markacino]

Thanks alot all. Have just ordered one. Fingers crossed it sorts out the issue and hopefully my a4 holds up until then before it refuses to start or something.

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[EuroxS4]

Check the suction jet pump and vacuum hose going to the brake booster.It is possible you have a vacuum leak there.

[markacino]

Check the suction jet pump and vacuum hose going to the brake booster.It is possible you have a vacuum leak there.

Cheers. I'll have a look when I get home. Generally should I hear something if it's got a leak or do I have to spray something on it to notice?

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[Gin+]

I'd check the pcv hoses and grommets underneath the intake manifold regarding a vacuum leak. They're a real pain to access without removing the intake.

[markacino]

So a bit of an update whilst I wait for the speed sensor to arrive.

Had to drive the car today, was going alright. As I'm driving along the highway the car shudders for a second then EPC light comes on. Made it to my destination.

Now when I turn car on, edc light is illuminated and does not go away when driving. The cars performance doesn't really seem any different since it happened.

Just thought I'd post this in case it changes anyone's diagnoses.

And thanks to those who suggested different areas for vacuum leaks. I can't find anything obvious that would indicate something wrong with the hoses but I'm clearly no expert.

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