Re: 4KQ OXS & rev limiter ?

[Glen_Powell@ne.3com.com]

New, heated OXY made no difference.   :(    Recent advice is to try
diddling the mixture screw in the metering unit. The larger engine, higher
compression, ported IM, head and EM combined with a very radical
long-duration and high-lift cam may have the calibration o for out that it
i not possible to detect via the O2 meter that the system might in fact be
in closed-loop. but cannot get any real action due to being sos far out on
the rich side.

What size hex is needed to adjust the mixture? I hear 3mm, but it does not
'feel' like it is engaging the adjuster. 2.5MM mebbe?

Other hints/suggestions?

Many Thanks!

-glen  pleaes respond to: glen_powell@3com.com




Huw Powell <human@nh.ultranet.com> on 05/07/99 03:51:01 PM

Sent by:  Huw Powell <human@nh.ultranet.com>


To:   Glen Powell/US/3Com
cc:
Subject:  Re: 4KQ OXS & rev limiter ?




> I need to get like 300-500 more RPM before the rev-limiter stops the fun.
> Any easy ways to do this? Is this controlled by the fool-pump relay?
Could
> the relay be modified to increase the rev limit?
afaik it's the fuel pump relay counting the coil signal.  sometimes 4
cyl fpr's wind up in our cars yielding a rev limiter at 5200 rpm.  I'm
sure there must be a way to fool it.  fpr from a CIS-E car with six
cylinders?
>
> Another question: I replaced the 3-wire heated oxygen sensor in my 84 4KQ
> RR car and also replaced the faulty HalMeter AF30 mixture meter. The
meter
> works OK now but it appears that the system never goes closed-loop. Is
this
> because the sensor does not get hot enough without the integral heater?
I ran an unheated oxs for a while, a long way from the exhaust ports,
and it still heated up.
> Does something sense the open-circuit for the heater and disable
> closed-loop mode?
No, because the exact same system and harness is in coupes with one wire
OXS (in the em), the oxs heater connector just dangles unused in those
cars.
>I would have thought that the heater was just for faster
> warm-up for emissions purposes and that it would eventually get hot
enough,
> guess not?
it should...
I bet something else is not right, though I can't tell you what - maybe
the ecu's engine temp sensor?  Which I think is the bottom one in the
top radiator hose flange.
--
Huw Powell
http://www.thebook.com/human-speakers
82 Audi Coupe; 84 4kq; 85 Coupe GT
http://www.nh.ultranet.com/~human