Lm4 running rich no codes
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Joined: Dec 2017
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Lm4 running rich no codes I've been having issues with my car running super rich lately. It's not throwing any codes and I just replaced the ECT sensor just for cheap posterity, but no such luck. It was running fine until it started all of a sudden one night. It was pretty hard to start and once it did I got about two blocks and it backfired and died. It only seems to be backfiring when coming off the throttle if I rev it up a few times. It's got a tune on it and hasn't had any problems up until now. The engine is an lm4 out of 2004 trailblazer running off an 98 ls1 camaro ecu with a Trickflow Trackmax Stg 3 cam, LS2 intake, LS2 injectors, ported truck throttlebody being supplied by an AEM 320 lph fuel pump and corvette fpr (checked fuel pressure and at its running at 60 psi) I'm not really sure what to check since its not throwing any codes and started so out of the blue. Did some research and I've seen that a guy had a similar problem and it ended up being his crank sensor could that be causing the issue in this case? Appreciate any help you guys could give me. Pictures were taken at idle.
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Joined: Dec 2017
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Replaced CPS and it doesn't seem to be backfiring anymore but still running rich enough to burn your eyes in the time it takes to get up to temp. I'm not opposed to reading up on something but I'm not really sure what to look up really. Any ideas?
