[Gmecm] Scan Tool and Olds ECM in '89 Electra Estate

[Steve Ravet]

> -----Original Message-----
> From: gmecm-bounces at diy-efi.org 
> [mailto:gmecm-bounces at diy-efi.org] On Behalf Of DANTE Mclean
> Sent: Thursday, November 09, 2006 10:45 AM
> To: gmecm at diy-efi.org
> Subject: [Gmecm] Scan Tool and Olds ECM in '89 Electra Estate
> 
> Hi:
> 
> I have an '89 Electra Estate with Olds 307 V8, eQJet.  
> Everything is stock.
> 
> What I want to do is drive around with my scan tool plugged 
> in for a few days to see if I can catch an intermittent code 
> 21.  Vehicle is usually fine, but throwing code 21 "TPS High" 
> every so often while idling at lights. 
>   TPS voltage looks to be within specs at idle when checked.  
> So this is truly an intermittent--and for more amusement, the 
> car has been fine all summer, but seems to start its little 
> antics as soon as the weather gets cool.

Have you tried replacing the TPS?  Or at least spraying some cleaner on
the connector and plugging/unplugging it a few times?  You could also
put an ohmmeter on there and slowly rotate it to see if the resistance
changes smoothly, and wiggle the wires to see if they're coming loose.

> 
> My scan tool (OTC 2000) allows State 6, Field Service, and 
> State 8, ALCL.  I understand that I should not run the engine 
> in Field Service for more than 2 minutes due to risk of 
> overheating the catalytic--A.I.R. divert--per OTC manual.
> 
> Can I road test in State 8?  The OTC manual says the vehicle 
> SHOULD NOT be driven in this mode due to increased Idle Speed 
> and extra spark advance (on fuel injected ... meaning not 
> applicable to this vehicle?).  "State 9 Road Test" is not 
> available with this ECM.

My '91 5.7L TBI has a field test mode that increases timing and idle.
If you drive in this mode for a few seconds you'll see why it's not
recommended -- it knocked horribly for me.  I don't know if the spark in
your car is controlled by the computer or not, though.  If not it might
be OK.

--steve