Vacuum and shift question
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Joined: Mar 2004
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From: Austin, Tx
Vacuum and shift question
I noticed lately that my 2002 F150 super crew automatic makes a thump when shifting at around 50 mph or higher. I think also when engaging the passing gear. What can this be?
Also, when going uphill, the A/C changes from vent to defrost on top of instrument panel then back when not under heavy load. I know its a vacuum issue but what exactly and why? Or is this normal?
I don't know if its me but I think my truck feels weak for having a 5.4 in it. All else is working fine as far as I can tell.
Also, when going uphill, the A/C changes from vent to defrost on top of instrument panel then back when not under heavy load. I know its a vacuum issue but what exactly and why? Or is this normal?
I don't know if its me but I think my truck feels weak for having a 5.4 in it. All else is working fine as far as I can tell.
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Joined: Dec 2001
Posts: 22,436
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From: Louisville,Ky.
I would check the tranny mount for the thumping noise.
You have a broken vacuum line. It is probably on the firewall near or behind the battery the goes into the fenderwell to the vacuum canister.
You have a broken vacuum line. It is probably on the firewall near or behind the battery the goes into the fenderwell to the vacuum canister.
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