Secondary Throttle Removal

[Paul Workman]

Originally Posted by GOLDCYLON

It would be great is somebody has written a step by step on how to do this. Im surprised the SES light dosent come on with everything removed. GC

Ah! It would, 'cept the ECM is re-programmed to accept zero vacuum as being OK, and the vacuum sensor, tho open now to the atmosphere, remains electrically connected (so the ECM knows it's there). So, having the chip modified is part of the gig.

When I had my chip re-programmed, it was part of a top end P&P and I opted to have the cooling fans & the idle characteristics (among some other features) included in the cal.

FYI, at idle, Marc's "no secondary throttle plates" calibration has the secondary injectors turned off. At 1 degree of throttle and above, the secondaries join the primaries and hello throttle response!

Pete is a "two-finger" typer, so he's skilled at packing it all in so few words. Gotta love 'im.

Originally Posted by Pete

You'll notice it'll pull/drive away from a stop nicer.

No more looking for vacuum leaks,actuators,solonoids,pump,vacuum lines,ect.

Pete

Although this pic was taken to document a problem with a gasket, one can see the hole left by the secondary throttle shaft in the secondary port. (And, one can see how the bosses have been "modified" around the injectors (1990 LT5), but that is another topic.)



P.