Re: Quad-4 (1228707 ECM) Rough Idle Problem

[Will Remaklus <remaklus@attglobal.net>]

I thought I sent this several days ago, but perhaps not...

To level set, this is a stock Quad-4 engine with a header.
I have not (yet) modified the engine control program or any
parameters.  That said, I modified a MemCal to use a 29F010/040
flash memory and have verified that it works...

>> The raw MAP sensor output is 70, +/-1 at idle.
>>
> That's really high, try adding some timing, less fuel, I'd try different
> settings to get something more along the lines of 55-60.  Your way off to
> the side of the map.

After examining the ALDL datastream a little closer and performing some
experiments with a vacuum pump, I need to change my previous idle MAP
value.  The raw ADC output is around 117 +/- a couple, which corresponds
to 53-55 kPa, when appropriately scaled.

> What Values (K/Pa) ya run at cruise?

When driving at 35 mph (1925 RPM), the MAP is 28-32 kPa.

I have deciphered a little more of the ALDL data stream.  At idle:

 * Advance varies from 10-20 degrees in a somewhat random manner.
   Why is the advance moving around?
 * BLM ranges from 80-100
 * At one point INT was stable at 114.  I blipped the throttle and
   it decayed to 107.  Ran the RPM up to 3000 for 15 seconds and
   then back at idle the INT went back to 108 and then decayed to 98.

At the beginning of this exercise the exhaust did not smell bad.
However, after the run at 3K RPM the exhaust had a very strong HC
smell.

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