[Navy Horn 16]

It was beautiful weather in central Texas yesterday and I brought the car out for a hill country drive. Everything was running great, I was blasting through back roads and had to do a small section of I-35. After merging, I hammered past a hapless Mustang put it in overdrive waited for a gap to get around an 18 wheeler and got back on the gas...the motor stumbled wouldn't accelerate, and basically fell on it's face. Traffic speed was fine, but accelerating over 3500 RPM wasn't happening.

I got off the highway, stopped at a light, got on it again and same crap through all the gears at 3500 rpm. WTF.. I pull over, check to make sure my distributor is locked down and my timing isn't AFU...all fuel lines are secured, nothing is messing with throttle linkages.

Luckily, I have a cousin who is a hell of a mechanic and I call him up and describe what's going on. His guess "your gas cap isn't venting". I check the cap, it doesn't hiss or anything. I check my fuel pressure while running, and it's a couple pounds low, but still at 4 which should be enough. I drive home, and the problem is now intermittent. Sometimes it will haul ass all the way to redline, other times it sputters. Pull into the driveway, check the gas cap again, and this time is hisses at me when I unscrew it.

$11 at O'Rilley's and the problem is fixed. I owe my cousin a meal, because I'd have never guessed the gas cap would cause that problem. I'd have had the top end of the motor off looking for an issue before I went to the gas tank..

So, if you ever have something like this happen. It might not be your engine builder that messed up, it might be the decades old plastic cap behind you that has given up the ghost.

Lessons learned cheap are the best ones.