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chris989 · 01-01-2012, 12:40 PM

Hello Pops,
i changed the the coolant sensor too.

yesterday i changed the electronic spark control and knock sensor and I will test drive after the brakes are fixed.

I have my suspicions about the timing. advancing itself via the computer causing the idle to rise, and as the timing corrects itself the idle returns.

All of the motors i have built in the past have been carbureted. even with my msd units i have not seen the timing swing like this. Sure they jump depending on the set curve but the engine is controlling the timing and this feels like the it is happening in reverse.
After setting the timing, and connecting the wire the timing will advance itself to 20 plus degrees and as i watch the idle come down so does the timing return to 8-10 .
I know all of this will get better gas millage when it is correct but right now i am dreaming of a new MDS.

01-01-2012, 12:40 PM	#4
chris989 Registered User Join Date: Dec 2011 Location: Boise, Idaho Posts: 557	Re: TBI slow to return to idle Hello Pops, i changed the the coolant sensor too. yesterday i changed the electronic spark control and knock sensor and I will test drive after the brakes are fixed. I have my suspicions about the timing. advancing itself via the computer causing the idle to rise, and as the timing corrects itself the idle returns. All of the motors i have built in the past have been carbureted. even with my msd units i have not seen the timing swing like this. Sure they jump depending on the set curve but the engine is controlling the timing and this feels like the it is happening in reverse. After setting the timing, and connecting the wire the timing will advance itself to 20 plus degrees and as i watch the idle come down so does the timing return to 8-10 . I know all of this will get better gas millage when it is correct but right now i am dreaming of a new MDS.