4kq acceleration issue

[Ben Swann]

Here are things to do and try - seems the car needs some sorting due to
neglect.  Once you get it sorted, it will be sweet.

 

- The valve cover leaks and the lifters clack pretty bad.

*** Well - seems like you need to replace valve cover gasket.  If you replace
lifters then do the gasket at that time.  Lifters are source of clacking.
Running higher/extended viscosity range ie. 20W50 may help - I like Castrol
GTX or even better Syntec 5W50.  Fix your leak before spending the money for
Syntec.  Try tightening the cover nuts uniformely to see if it helps with the
leak - don't overtighten.  Try running good quality oil before getting into
lifter replacement - these engines like higher viscosity oil again non-synth
20W50 (or 10W40 if in cold climate) or 5W50 synthetic and you can run it year
round.

 

- It idles high, usually a little above 1000.

*** Couple probable causes include: vacuum leaks; Idle stabilizer valve or
circuit - likely culprit is the idle switch - check/repair/replace - they all
go bad over time;  Replace vacuum lines.  You'll likely find some obvious
culprits.  A lot of folks immediately assume ISV is bad - more likely it is
the idle switch and/or throttle body screw o-ring.  Try jumpering the idle
switch connector and see if the idle drops.

 

- It has some trouble starting in the cold.  The colder it is, the harder it
is to start.

*** As above - vacuum leaks likely culprit.  Also Injector seals.  Might be
Fuel Injection Thermo Sender, but do the other repairs first.

 

- I have to give it some gas to get it to idle steady but then its good to go.

*** As above - air leaks.

 

- Sometimes it will almost stall until I get the car moving and then it's ok.

*** Air leaks!

 

- The temperature gauge usually sits between the 1/2 to 3/4 mark unless I have
the heater on and then it drops down to between 1/4 and 1/2.

*** Normal

 

-        The motor diesels.  

*** Running too lean - air leaks.  Possible other cause, but fix most probable
causes first.

 

*** You need to spend a good day sorting it out.  Be equipped with about 10'
of good quality vaccum line and some rubber hose bandage tape to repair any
OEM hoses that may not be readily available.  Replace the Air Filter and clean
out all the garbage.  Clean up the throttle plate area too while you are at
it.

 

Ben

http://www.GTQuattro.com

 

 

[Date: Mon, 12 Feb 2007 23:56:36 -0800

From: "Rory [Armodis.List]" <armodis.list at gmail.com>

Subject: 4kq acceleration issue

To: quattro at audifans.com

Message-ID:

      <7d2189420702122356ra130bd1x606aa5094fdb11d0 at mail.gmail.com>

Content-Type: text/plain; charset=ISO-8859-1; format=flowed

 

Hey audifans

 

I have a stock 85 4000 quattro that needs a lot of love =)  Based on a couple
references from audifans, I believe the car has an Inline 5 2.2L 10V CIS-E.

 

- The valve cover leaks and the lifters clack pretty bad.

- It idles high, usually a little above 1000.

- It has some trouble starting in the cold.  The colder it is, the harder it
is to start.

- I have to give it some gas to get it to idle steady but then its good to go.

- Sometimes it will almost stall until I get the car moving and then it's ok.

- The temperature gauge usually sits between the 1/2 to 3/4 mark unless I have
the heater on and then it drops down to between 1/4 and 1/2.

- The motor diesels.

 

The fuel pump, fuel pre-filter, and fuel filter have all been replaced.

I do not know when the plugs, wires, cap and rotor were last replaced.

 

Last night the car suddenly started having acceleration problems in any gear.
I kept the RPMs above 4000 and the acceleration problem seemed to go away long
enough for me to get on the highway and get home.  This morning and through
the day the car seemed to function as it usually does.  Tonight the
acceleration problem came back and didn't go away.  I limped it home and could
smell something burning, but didn't get a good whiff.  I think it was plastic
like.

 

In looking at the Bently it seems this could be caused by a leak in the air
intake system, differential pressure outside of tolerance, or several other
things.  In searching through the archives I found several references to the
air intake leak and one about the oxygen sensor.  I tried removing the oil dip
stick as recommended in a post from the archives to test the air intake issue,
but that didn't change anything.  Several posts are in reference to turbo
motors, so I'm not sure how that plays into things.

 

I know the car has quite a few issues that could cloud what is causing the
acceleration problem, but any ideas on where to start or what is most likely
to be the problem would be deeply appreciated.  If there is anything I *must*
do to narrow the problem down please let me know (ensuring the idle screw is
tightened down?).  I'm saving my pennies for a motor swap, so I'd be happy if
I could just get it running fairly normal again.  Hopefully long enough to
make it through snowboarding season =)

 

Thanks in advance!

Rory]