Vacuum problem

2001 TOYOTA TUNDRA
170,000 MILES • 3.4L • 6 CYL • 2WD
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RDGRIMES
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I replaced the valve cover gaskets and the plenum gaskets and now when I start it it will not idle and it backfires. I just watched your video and unplugged the MAF. And then I unhooked the throttle position sensor. And it runs at about 2500 rpm nice and smooth. If I plug in the TPS, it chokes and shuts off. The TPS looks to be operational but I am guessing that that is the problem. So I was facing two issues. The air intake was disconnected and the MAF was still plugged in, and the throttle position sensor apparently is bad.
Apr 17, 2018 at 8:45 AM
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MHPAUTOS
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I would start with checking that the plenum gaskets have not moved and you have a vacuum leak there.
Apr 18, 2018 at 4:10 AM