5.3 Runs good for 1 driveway pass
06-28-2016 | 11:01 AM
#21
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Joined: Jun 2016
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Without being there looking at scanner data while it's acting up, I cannot help beyond the following.
Check 02 sensor wires to be sure they are on the correct side. If they are mixed up, it will cause 1 bank to go dead lean and the other to go dead rich, but only after it goes into closed loop.
Unplug the MAF, you said it was new but not if it was aftermarket. Only the GM ones are proven to work correctly. By unplugging the maf, it will set a SES light but it will revert to the speed density tune. If it doesn't run any better, then it would probably rule out the MAF as a cause.
With the MAC scanner, you should be able to watch fuel trims, see if they go positive or negative and how each bank relates to the other. This info will help others to help you.
Check 02 sensor wires to be sure they are on the correct side. If they are mixed up, it will cause 1 bank to go dead lean and the other to go dead rich, but only after it goes into closed loop.
Unplug the MAF, you said it was new but not if it was aftermarket. Only the GM ones are proven to work correctly. By unplugging the maf, it will set a SES light but it will revert to the speed density tune. If it doesn't run any better, then it would probably rule out the MAF as a cause.
With the MAC scanner, you should be able to watch fuel trims, see if they go positive or negative and how each bank relates to the other. This info will help others to help you.
06-28-2016 | 11:35 AM
#22
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06-28-2016 | 01:20 PM
#24
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Already checked this and they were right. After I saw the graph from the bank 2 fuel trims I pulled the injectors and found the plastic housing at the end of 2 of them had been flattened in. Guess I wasn't careful enough moving the intake around when I was building the motor.
07-02-2016 | 07:56 AM
#25
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Joined: Oct 2015
Posts: 310
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I had similar issues. It was not enough air getting into the motor at low rpms. Need to get your iac dialed in before moving to any other issue.I had to run tps to 4 percent before it would idle so turn my throttle stop to roughly 4 percent. I was able to starting tuning when warmed up after iac was in check
07-02-2016 | 11:39 AM
#26
You need a different pump. That pump is rated for 43PSI at full electrical load. I am not surprised it's only able to output 50 PSI total
Once you sort this out, Then get the tune corrected.
FROM AEM: Power rating given at 43 PSI, 13.5 Volt at the pump with a BSFC of .5, flow capability for horsepower support is ultimately dependent on fuel hose diameter and system electrical voltage and amperage capabilities
07-02-2016 | 04:25 PM
#27
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I replaced it with the exact same pump, put some new AN hose on, and a new FPR and have 56-58psi at idle, goes over 60 with a blip of the throttle. Still ran like crap in closed loop. Unplugged both my o2 sensors and it runs great all the time. Going through the o2 wires now to check for continuity, checking grounds and if that doesn't fix it I'll get new o2 sensors. Anybody have experience running the vette rear o2 sensors?
07-12-2016 | 01:51 PM
#28
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I replaced it with the exact same pump, put some new AN hose on, and a new FPR and have 56-58psi at idle, goes over 60 with a blip of the throttle. Still ran like crap in closed loop. Unplugged both my o2 sensors and it runs great all the time. Going through the o2 wires now to check for continuity, checking grounds and if that doesn't fix it I'll get new o2 sensors. Anybody have experience running the vette rear o2 sensors?