Hello All! I’ve became victim to the p0401 code. And I’ve searched forums for days nows. Code reads as p0401 EGR flow insufficient. Car runs and drives completely fine no hesitation or anything. Idles perfectly.
I removed the egr valve 1 vac line,2 bolts,& 2 coolant hoses. Cleaned egr, cleaned intake port, and cleaned gasket. Performed a vacuum test on the egr and it held vacuum. Then added fluid to one side of the chamber and it didn’t leak through, pulled a vacuum which moved the diaphragm inside and the fluid leaked into the other chamber. Conclusion is that the egr valve itself is fine.
Now removed the the egr solenoid 2 bolts, 2 vac lines, 1 connector. Performed another vacuum test. Without power to the solenoid it leaked down. Added power and it held a vacuum. So now the solenoid is fine.
Removed throttle body noticed the gasket was in fact on wrong. It was flipped to the wrong side. Also covered in gasket sealant. The sealant had a noticeable indention on the gasket for the chambers E & A indicated on top of the TB. The chambers run to vacuum lines on top of the TB. Wonder if the sealant clogged part of the ports for E & A had was causing insufficient flow?? Cleaned the TB and intake and replaced TB gasket.
I done all of this within the day and drove the car for roughly 20 miles and no light. I had the battery disconnected so I’m assuming it’s now through the drive cycle. Hooked my scanner up and the code is under pending. (I didn’t clear the code before or after repairs) Was reading about a resistor inside a white dashed vac line? Could anyone pin point location? And location of a vacuum controller? Hopefully it will pass emissions come Monday morning I’ll update soon.
I removed the egr valve 1 vac line,2 bolts,& 2 coolant hoses. Cleaned egr, cleaned intake port, and cleaned gasket. Performed a vacuum test on the egr and it held vacuum. Then added fluid to one side of the chamber and it didn’t leak through, pulled a vacuum which moved the diaphragm inside and the fluid leaked into the other chamber. Conclusion is that the egr valve itself is fine.
Now removed the the egr solenoid 2 bolts, 2 vac lines, 1 connector. Performed another vacuum test. Without power to the solenoid it leaked down. Added power and it held a vacuum. So now the solenoid is fine.
Removed throttle body noticed the gasket was in fact on wrong. It was flipped to the wrong side. Also covered in gasket sealant. The sealant had a noticeable indention on the gasket for the chambers E & A indicated on top of the TB. The chambers run to vacuum lines on top of the TB. Wonder if the sealant clogged part of the ports for E & A had was causing insufficient flow?? Cleaned the TB and intake and replaced TB gasket.
I done all of this within the day and drove the car for roughly 20 miles and no light. I had the battery disconnected so I’m assuming it’s now through the drive cycle. Hooked my scanner up and the code is under pending. (I didn’t clear the code before or after repairs) Was reading about a resistor inside a white dashed vac line? Could anyone pin point location? And location of a vacuum controller? Hopefully it will pass emissions come Monday morning I’ll update soon.