Question for HUW Powell or anyone else

[Bill Green]

Yes I’m using the JT ECU. Thanks for tip regarding the knock sensor setup. I
do have the sensor itself as well as the original NG distributor both of
which are brand new. 

I haven’t cleaned the ISV yet but plan to very soon as suggested. I’ve had
to use the JT ISV because I’m limited by what the JT wiring harness will
connect to. The JT ISV is about ½ the size of the NG ISV. That may be part
of the problem? The duty cycle from the JT is running in the 40% range on
the NG. I see no way allow more air to bypass the throttle body in order to
reduce the Duty cycle to 25 – 30% as it should be. The JT ISV has three
wires vs. only two for the NG ISV. I wonder if I could interchange them
somehow? 

 

 

From: Tony Hoffman [mailto:auditony at gmail.com] 
Sent: Tuesday, July 31, 2012 4:32 PM
To: Bill Green
Cc: quattro at audifans.com
Subject: Re: Question for HUW Powell or anyone else

 

So, you still have the original ECU from my understanding? If that's the
case, adjust everything to original 4000Q specs, as that's the management
system you are using and adapting to. As for the knock sensor setup, it's
pretty easy to put one in from an 85-86 GTI/GLI 8v. COmpletely self
contained, having nothing to do with the fueling system. That's what I've
done on several cars where I've installed a high compression engine where
there wasn't one originally. And, they use the stock distributor as well.

 

Have you cleaned and checked the ISV?

 

Tony

On Sun, Jul 29, 2012 at 12:13 AM, Bill Green <wgreen56 at tampabay.rr.com>
wrote:

Hi again!


You may remember me as I am the lad who thought a loose starting motor was
really a serious knock in his new NG engine he just installed in Audi 4000s
quattro. The engine is installed now and seems to run strong. The only
problem is a brief stumbling when going to back to idle from higher rpm
before calming down and idling fine at about 750 rpm.


My question is whether I should set the initial  mixture setting on the air
handler (using a rig exactly like the one you made to measure the milliamps
between the ecu and the differential pressure regulator) so it fluctuates
around 10 milliamps or 0 milliamps. I am using the original NG injectors and
a fuel distributor / DPR from an Audi 90 which had a NG engine in it. The
ecu and the air handler however are both from the original JT engine with
CIS-E  not CIS-III. I currently have the base mixture set to hunt around 10
milliamps.


By the way the distributor is also from my old JT engine which utilizes a
vacuum advance setup since I don't have (and don't really want) the knock
sensor / electronically controlled timing thing.