Re: 4kq rough cold idle

[ejfluhr@austin.ibm.com (Fluhr)]

>Oh, if it helps any, I have a back fire when I let off the gas at
>speed but if I open the throttle just a tad it goes away. 


Is this "backfire" continous when you are decelerating off-throttle, or
just once?

If it is continuous, then I'll bet your idle switch is mis-adjusted or
broken.  If it is not working correctly, the CIS-E fuel injection system
continues to provide fuel to the engine, thus making a noise which sounds
like backfiring (or really cool burbling, IMO).  If the idle switch is
working, then the CIS-E control unit will cut fuel flow when the rpms
are significantly above idle. 

If your idle switch isn't working, then you cannot be sure that your
idle mixture is correct.

Later,
Eric
'85 Coupe GT
---
Eric J. Fluhr                                Email:  ejfluhr@austin.ibm.com
630FP Logic/Circuit Design                   Phone:  (512) 838-7589
IBM Microelectronics Div.                    Austin, TX