P0402 Troubleshooting : Jumper the Lines?
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P0402 Troubleshooting : Jumper the Lines?
I'm getting P0402 code but no other noticeable issues.
I was wondering if simply jumping the DPFE inputs with one hose and the EGR tube with the other and waiting for another P0402 code to show up is a reasonable way to identify a bad DPFE sensor?
Of note is that I replaced the exhaust manifolds, EGR tube, and EGR valve about 10,000 K ago and the code just begun appearing. The EGR tube was completely rusted out at the manifold which also had leaks. Still no detection of any EGR flow problems back then.
I was wondering if simply jumping the DPFE inputs with one hose and the EGR tube with the other and waiting for another P0402 code to show up is a reasonable way to identify a bad DPFE sensor?
Of note is that I replaced the exhaust manifolds, EGR tube, and EGR valve about 10,000 K ago and the code just begun appearing. The EGR tube was completely rusted out at the manifold which also had leaks. Still no detection of any EGR flow problems back then.
Lead Driver
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Your EGR system is not tight at some point between the internal orface of the tube and the intake manifold port behind the EGR valve.
Or the DPFE is faulty.
The 402 code is 'excessive' flow detected on a test of the EGR system.
This is one of several different tests to determine the integrity of the whole system independent of the actual dynamic operation.
The PCM program has a test routine that signals the EVR to gate vacuum to the EGR to open the EGR a calibrated amount.
The DPFE then measures the flow.
If it is out of limits the code is set.
If the DPFE cannot function, the PCM sets the code either way.
Check all the hoses and connections.
Check the EVR for sticking open allowing the EGR to hang open some amount.
You can't do any work around or test of that nature.
Good luck.
Or the DPFE is faulty.
The 402 code is 'excessive' flow detected on a test of the EGR system.
This is one of several different tests to determine the integrity of the whole system independent of the actual dynamic operation.
The PCM program has a test routine that signals the EVR to gate vacuum to the EGR to open the EGR a calibrated amount.
The DPFE then measures the flow.
If it is out of limits the code is set.
If the DPFE cannot function, the PCM sets the code either way.
Check all the hoses and connections.
Check the EVR for sticking open allowing the EGR to hang open some amount.
You can't do any work around or test of that nature.
Good luck.
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Thanks, BG.
A little cooler today and no city driving - also no codes.
I've already checked the 2 DPFE sensor hoses (1 was tight but was able to snug a bit more) and I'll check the connections to the EGR and manifold to see if they have loosened off at all. I did lather both up with anti-seize when I replaced the front end of the exhaust. New gasket on EGR as well.
A little cooler today and no city driving - also no codes.
I've already checked the 2 DPFE sensor hoses (1 was tight but was able to snug a bit more) and I'll check the connections to the EGR and manifold to see if they have loosened off at all. I did lather both up with anti-seize when I replaced the front end of the exhaust. New gasket on EGR as well.
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Found I was able to tighten the input to the EGR slightly (?anti-seize shrinkage).
Everything else is tight.
While in there I found the "Fuel Vapor Tube" or rubber gas vapor return hose is really deteriorating and plan to replace this with some 3/8" ID fuel line. This is a different system, however.
Not changing until I monitor the original P0402 issue for a few days.
Everything else is tight.
While in there I found the "Fuel Vapor Tube" or rubber gas vapor return hose is really deteriorating and plan to replace this with some 3/8" ID fuel line. This is a different system, however.
Not changing until I monitor the original P0402 issue for a few days.
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