ping

Carl Summers intech at writeme.com
Tue Aug 24 07:52:22 GMT 1999


Hi David,
      PE is Power Enrichment......that table is used for correcting the air 
fuel ratio once PE has been set.....if you have many mods, that table will 
have to be adjusted......if this is a new problem,,,,I agree with the group 
you might have a wiring or injector problem.....hth's
-Carl Summers

mailto:intech at writeme.com
Click on the above link to respond privately.

-----Original Message-----
From:	David Mulvey [SMTP:kd6bzn at QNET.COM]
Sent:	Tuesday, August 24, 1999 12:09 AM
To:	gmecm at efi332.eng.ohio-state.edu
Subject:	Re: ping



> It sounds to me like the knock sensor is NOT working and/or egr problem. 
The
> best way to check the knock sensor is to take a plunger handle, and drop 
it
> with it's own weight only onto the block near the knock sensor.  Watch 
the
> timing, (Scan tool) and make sure the ecm is pulling some timing out.  I
> have never heard of twisting the wires.  I have ALL the tech bulletins on
> the L98.  I have tuned the knock sensor a bit by using a bit of teflon 
tape

The twisting of the wires is just a simple way of keeping some low 
frequency RF from resonating on a stran of wire.  As long as the
wire twists the RF has only very small untwisted sections to resonate.

I checked the EGR valve and the EGR solenoid and the voltage to the 
solenoid.  All Ok, a good vaccuum to the egr valve caused the
motor to idle down..  I cleaned out the EGR solenoid gave it a test on a 12 
volt power supply. So EGR I think it fine.

I do have one old injector on the side of the engine that doesn't have the 
O2 sensor. Could be a suspect.  I have 3 old injectors on
the O2 sensor side, and do not get any mixture errors.

I was wondering about the Knock sensor too.  I do get error 43 which I 
think is the code showing that the knock count exceeded it's
limits. An audible ping/knock is also heard at this time.  I guess I was 
wondering if the knock sensor maybe was only working a little
not detecting the all of the knocks then causing the computer not to adjust 
properly then setting off the MAF voltage too high and/or
too low..  Kinda getting complicated at this point.

I still need to check the ground to the MAF sensor.
I still need to give the knock sensor wires a couple of twists.
I want to replace the 4 old injectors I have, (short on funds at the 
moment)
AutoZone has injectors for $35 each.
Am I buying crap or are these things workable?
AutoZone also has MAF sensors for $139,
$80 core charge. (got one the other day, same 'ping')
practically everything else is new except for the ESC module.
I figured the ESC is probably working since
I do have a car that runs.. Good assumtion?
I need to see if the knock sensor is working using the plunger stick test.
I haven't gotten into changing ECM values yet.  Will not hesitate if 
nothing else seems to work.
"PE vs. RPM table"  =- What's 'PE'?

For the Knock sensor test would I notice a timing change using the plunger 
handle and a timing light? I got one of those..


end
----
David Mulvey KD6BZN
Lancaster, CA
(661) 723-0352



More information about the Gmecm mailing list