4kq acceleration issue

[Huw Powell]

Thought I'd chime in here too... first, there's the rather obvious joke 
presented in the subject line.  Even at full performance, that 115 hp 
can seem rather anemic to those used to today's 200 hp cars.

But, that said, a properly working 4kq is at least a brisk, smooth 
accelerator.

> 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.

That is correct.

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

Both common symptoms.  New rubber (not cork) valve cover gasket is about 
$20; the nuts must be torqued very gently or a new one will leak, too.

An oil change or two might quiet the lifters down a bit, if you really 
can't stand it, they're about $60 or a set, and not too bad to replace 
if you're used to "inside the engine" mechanical work.

> - It idles high, usually a little above 1000.

These are mostly repetitions of previous answers - 1. test idle switch; 
2. check every bit of rubber under the hood for leaks.  A common one to 
split where you can't see it is the four way hose just forward of the ISV.

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

Most likely air leaks; can be made worse by people adjusting the static 
mixture to try to sompensate for them.

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

That's a good sign, at least you are "near" it working properly.

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

Ditto the air leaks etc...

> - 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.

Those are normal observations.

> - The motor diesels.

It shouldn't.  This may also make it harder to start.  After you turn 
off the key, the fuel pump stops.  The only fuel available to "diesel" 
is the residual pressure, which you want to be there for when you next 
start the car.

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

Good.

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

So install new ones.  Then you'll know when they were 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.

Could be random crud on the engine burning, from the heat of running 4k 
rpm a lot.  If it seemed to breathe ok at 4k rpm, it's not a clogged 
cat, that would prevent revving.

> 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. 

That wouldn't affect your engine system.

> 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. 

I'd start with the basics - make sure the "tune up" type parts are good 
or new.  Go through the vacuum hoses and molded rubber bits and clean 
them up.  Check the timing.  Make sure the OXS is working.  Check the 
static mixture after doing these things.

Bookmark this file and check everything:

http://www.humanspeakers.com/audi/tuning-cise.htm

> I'm saving my pennies
> for a motor swap, so I'd be happy if I could just get it running
> fairly normal again.

How soon the motor swap, and to what?  Not sure it makes sense to buy 
new ignition parts or lifters if you're going to another engine (your 
used JT is worth more as scrap than as an engine, no one needs them 
because they last forever)

But addressing vacuum issues, cleaning and gapping plugs, checking 
timing and mixture, are all good practice for getting the new engine 
running right anyway, and not expensive.  You can get a bit more out of 
crappy spark wires by cleaning them and spraying with silicone.  Cap and 
rotor can be cleaned, too.  Vacuum lines are cheap and molded rubber 
bits can be cleaned thoroughly and repaired with RTV, sometimes quite 
effectively.

-- 
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/