P0405 code
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Teching In
Joined: Feb 2021
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P0405 code have a 2000 Trans Am. I've thrown the p0405 code a couple of times for low-voltage on the EGR valve. It seems to happen when I do a hard acceleration. Most often if I'm on the freeway doing 70 and then I punch it and kick it up to 90 I'm just take my foot off accelerator it starts coughing and choking and throws the code. I took it to a shop they seem to think it's something in the wiring harness but they haven't been able to find it. I think it might be something to do with a weak or bad motor mount that causes the motor to twist and pulling wiring somewhere does anybody have any thoughts
Thread Starter
Teching In
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TECH Senior Member
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From: Central Cal.
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Disconnect EGR and test to confirm no issue. Trace wires from EGR to PCM to confirm no issues. You could do a wiggle test while monitoring the EGR supply signals at the EGR and position sense signal at the PCM and look for erratic signal. If all good, replace EGR.
