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Captain J · 11-18-2017, 06:03 PM

Thanks Sabaka454
Maybe you’re right, my question
When driving, the gear will not shift from 1st to second at low speed (as normal), it shifts at higher speed 30-40mph, otherwise it will stay in 1st gear.
What causes the gear to shift at higher speed? Is it the MAP sensor which I recently changed? Or something else?
Nothing was done to the transmission.
Only the TBI, was overhauled
I hope it’s clear.

11-18-2017, 06:03 PM	#4
Captain J Registered User Join Date: Nov 2017 Location: H, Q Posts: 180	Re: 87 GMC issues Thanks Sabaka454 Maybe you’re right, my question When driving, the gear will not shift from 1st to second at low speed (as normal), it shifts at higher speed 30-40mph, otherwise it will stay in 1st gear. What causes the gear to shift at higher speed? Is it the MAP sensor which I recently changed? Or something else? Nothing was done to the transmission. Only the TBI, was overhauled I hope it’s clear.