P0401 - EGR flow insufficient on ES300 "97+
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#21
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Ok. Your car doesn't have an EGR modulator, it has a vacuum check valve instead. The EGR VSV is the one that controls the vacuum flow to the vacuum check valve and this valve passes vacuum to the EGR.
The VCV is purple and you need to remove the engine cover. Get a vacuum pump, pump the middle port and plug the outer port and vacuum should hold around 4.4 - 7.1 in Hg. If it doesn't vacuum check valve needs to be replaced.
The VCV is purple and you need to remove the engine cover. Get a vacuum pump, pump the middle port and plug the outer port and vacuum should hold around 4.4 - 7.1 in Hg. If it doesn't vacuum check valve needs to be replaced.
Last edited by GS4_Fiend; 06-20-13 at 09:59 AM.
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Ok. Your car doesn't have an EGR modulator, it has a vacuum check valve instead. The EGR VSV is the one that controls the vacuum flow to the vacuum check valve and this valve passes vacuum to the EGR.
The VCV is purple and you need to remove the engine cover. Get a vacuum pump, pump the middle port and plug the outer port and vacuum should hold around 4.4 - 7.1 in Hg. If it doesn't vacuum check valve needs to be replaced.
The VCV is purple and you need to remove the engine cover. Get a vacuum pump, pump the middle port and plug the outer port and vacuum should hold around 4.4 - 7.1 in Hg. If it doesn't vacuum check valve needs to be replaced.
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So basically I have to take the purple one out and vacuum the middle port and measure the pressure at the outer port? Do you know the PN for this part? I might just replace it instead of take it to the dealer for the measurement. I don't have tools at home.
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To be more precisely, are the middle and out ports as I circled in the picture? Do you also think it might be the problem coming from the sensor on the EGR Valve?
Last edited by ibuddler; 07-02-13 at 02:30 PM.
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