So I think I messed up replacing the air pump on my '90 F350 7.5L. It barely accelerates now, and my high temp hoses are melting near the CAT. I’m wondering if I crossed some hoses or something? The air pump has four fittings, and I’m confused about where they all go. Anyone have any idea how these hoses are supposed to be connected?
It sounds like there might be a check valve issue. The hose from the pump to the diverter valve could be connected wrong. That’s the one that directs air to the exhaust or CAT.
velmak said:
It sounds like there might be a check valve issue. The hose from the pump to the diverter valve could be connected wrong. That’s the one that directs air to the exhaust or CAT.
I think that’s where I messed up… I might’ve crossed two of the fittings. Can you remind me what the diverter valve is?
@Troy
The diverter valve is crucial for directing airflow to the exhaust manifold or the catalytic converter. Double-check that connection!
The check valve might be the problem here. If the hose to that isn’t right, it could cause overheating or backflow issues.
Davis said:
The check valve might be the problem here. If the hose to that isn’t right, it could cause overheating or backflow issues.
Yeah, I think that’s the issue. I’ll check the connections this weekend to see if I got it wrong.
The canister you mentioned on the right fender is probably part of the emissions control system, like the charcoal canister for fuel vapor recovery.
STEEVE said:
The canister you mentioned on the right fender is probably part of the emissions control system, like the charcoal canister for fuel vapor recovery.
Ohhh, that makes sense. I had no clue what it was for. Thanks for pointing that out!
If your hoses are melting, something might definitely be crossed. Make sure the outlet hose is connected properly to the diverter or check valve.
Kai said:
If your hoses are melting, something might definitely be crossed. Make sure the outlet hose is connected properly to the diverter or check valve.
Yeah, I’m definitely gonna look up a diagram to make sure. Thought I had it right but clearly not, lol.
Had this same issue before. Check that the air bypass valve is connected correctly to regulate excess air. That was my problem.
Easton said:
Had this same issue before. Check that the air bypass valve is connected correctly to regulate excess air. That was my problem.
Good tip! I’ll check the bypass connections and make sure they’re right. Thanks!