Warning: chased an exhaust leak on my '87 F150 for 6 weeks straight

Replaced gaskets, the manifold, even the whole Y-pipe, but it was a hairline crack in the EGR tube that I only found by spraying soapy water at 2 AM. Has anyone else been burned by a stupid little part like that?

2 comments

2 Comments

bettyhunt1mo ago

Nah, you're giving the soapy water trick way too much credit. That's not some magic bullet, it's just the last resort after you've already wasted six weeks chasing ghosts. Most guys would have found that crack way sooner if they'd just pulled the EGR tube and looked at it with a flashlight instead of assuming it's fine. The real issue is that people get tunnel vision and swap parts without actually diagnosing the problem step by step. Soapy water at 2 AM is just the universe punishing you for not thinking ahead. You got lucky, plain and simple, because half the time those cracks only show up when the engine is hot and the metal expands anyway. Next time do a proper smoke test or use a propane torch around the EGR system before you throw a bunch of money at manifolds and gaskets that weren't even broke.

grayb641mo ago

Wait, you found it with soapy water at 2 AM? That's rough, but at least you got it sorted. I gotta say though, you probably should have checked the EGR tube way earlier than six weeks. Those hairline cracks are a classic headache on the 5.0L and 4.9L engines from that era, they love to hide where you can't see them. Next time, hit the whole EGR system with the soapy water first before you start swapping manifolds, it'll save you a ton of late nights.