re. 4KQ Idle wandering? Questions and Thoughts.

[Swann, Benjamin R. (BSWANN)]

Rick,

I had had some intermittant flakyness prior to installing the 264 cam.  It
was exacerbated somewhat after installing the cam, although the power and
smoothness was notable during acceleration after Cam installation, which
included new lifters.

Here are among the things I did since to resolve drivablity especially rough
idle and warm-up weirdness: 

Thermo-sensor located on bottom of cooling feed to head - helped, but not
perfect.

New wires, plugs, cap-and rotor - helped but not perfect.  Incidentally had
to replace the thermo-time sender/switch located on top of cooling feed to
head, as it snapped when removing connector.  I had also found the crankcase
breather hose was failing/failed when I removed to clean.

New/used cat(mine still had good core, but had to remove to find out).  This
was mainly to replace the OXY sensor - engine now runs smooth, but had some
idle bounce.

Adjusted throttle screw up a tad - no idle bounce, but idles a tad high..
around 900 RPM.

I know everything is tight, and fuel injectors, pump and filter were
replaced awhile back and the fuel pressure regulator cleaned, BG44K, etc..
Car idles fairly well now, but not perfect, still some tweaking is in order.
Engine pulls solidly past to redline where I discovered there is an
ignition/fuel pump cutout.  I probably still need to adjust the mixture, as
I had progressivly enriched prior to replacing OXY sensor.

At this point, I have no real incentive to continue with project 4KQ(87.5
GTCoupe engine mod & transplant), but will anyway, just not as fast, as I
expect the novelty of new found power will wear out soon.  I expect
something will have to break (uhoh!) for my wife to allow me to proceed with
the swap{;0}even though I already spent the $$$.

In short, there were probably several marginal components that added up to
mediocre running that may need to be resolved.  I hope this helps.

Regards,

Ben
http://www.homestead.com/Ben_Swann/myaudi.html

BTW - 282 is a rather agressive stick to be running in the low compression
stock motor.  IMHO you'll have to work diligently to get it to idle
correctly, but it should not hunt/wander.

p.s.Anyone need a complete 2.3l setup with ELGIN 272 CAM?  I have a boat
which needs work - too many projects for now.

[In my 4KQ I have an aftermaket cam shaft, and its pretty big. 282 to be 
exact, and needless to say it changed the way my car runs greatly, the 
horsepower increase is large but the starting and running of the car is 
terrible.  It only has trouble cold staring, and in warm weather it runs 
like a top but lately when I come to a stop after driving, the idle wanders 
up and down up and down like a balance scale but never levels out. Each time

it dips it gets progessevly worse.  We have disconnected the O2 sensor 
because the car runs better on a fixed CO setting, but I want to know what 
else could cause the hunting or wandering of my idle like that, temp sensor?

ignition?  Any thoughts clues.  I have had the cam for about 4 months now 
and when the car is in motion it pulls hard, and runs like NEW, just idle 
and start up sucks, the idle lopes, but that is not the wandering problem, 
the lope is due to the large duarion, i know that, so any help or advice 
would be apriciated.  Thanks.

-Rick Heinlein
1987 4000CS Quattro w/super suspension
http://www.rickyphunk.iwarp.com/carpage.html]