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Low A/F ratio and no boost

312 Views 4 Replies 2 Participants Last post by  Saml810
for the past month I’ve been pulling both P0172 and P0134 and haven’t been able to build any boost/ had a fuel cutoff when getting to the threshold of building boost and the I/C spray light flashes in about 20 second intervals on startup.
I replaced the exhaust manifold because it had a crack in it replaced both front 02 and verified that I don’t have an exhaust leak and I’m doing a boost leak test later this week.
I’m stumped on what the issue could be I’ve looked around the other forums and haven’t found anything if anybody has any ideas it would be greatly appreciated
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Sounds like you're running really really rich. Could be down a cylinder on spark or have a major boost leak or you have stuck open injector or there's an issue with your tune.
I’ll take a look into that but, would any of those issues cause the P0134/bank 1 sensor 1 no activity detected code?
Unless you're so rich that it's out of range, it's most likely that O2 sensor is dead. If that code came later, running super rich for too long could clog up/ruin the front O2 and eventually your cat.
The P0134 Code was the first one that popped up and then recently the P0172 came
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