The service engine soon (SES) indicator illuminated, so went to my local Autozone to have the code read. The scan returned "Code 0401 Exhaust Gas Recirculation insufficient flow". They wanted to sell me a new EGR valve, but I declined and went home to investigate myself before shelling out any cash.
This is what I found. Notice the L-shaped, disintegrating vacuum line. It was so degraded that it had fallen off on its own. One end connects to a hard line that runs to the back towards the firewall, the other connects to one leg of a tee. The middle part of the tee connects to a solenoid and the other leg of the tee connects to a 2" piece of hose which connects to a hard line that travels under the air intake towards the firewall on the battery side. Not sure, but it seems like this could be the main source of vacuum for the system.
A little closer view.
Back to Autozone for some hose. The only thing they had that was close to the ID of the original hose was some fuel line. They found a little piece about 6" long in the back and just gave it to me. Thanks AZ man. Fuel line is quite a bit stiffer than vacuum line, so I put a tiny bit of silicone grease in each end with a q-tip to help it slip together. While I was there I replaced the 2" piece on the other side of the tee as well.
Here's a after-fix photo
I had noticed a few months ago that the engine was idling rough. I also noticed the gas mileage was slowly decreasing, the left front hub would occasionally clatter and the HVAC air would not change from defrost to the vents until 5-7 minutes after the vent button was pressed. I suspected that there was a vacuum leak somewhere, but hadn't really had the time to investigate. I'm glad the SES light forced me to give it some attention because it runs so much smoother and has more power now that it's fixed. And, no more SES light!
Hopefully this will be helpful to anyone having vacuum challenges too.
This is what I found. Notice the L-shaped, disintegrating vacuum line. It was so degraded that it had fallen off on its own. One end connects to a hard line that runs to the back towards the firewall, the other connects to one leg of a tee. The middle part of the tee connects to a solenoid and the other leg of the tee connects to a 2" piece of hose which connects to a hard line that travels under the air intake towards the firewall on the battery side. Not sure, but it seems like this could be the main source of vacuum for the system.
A little closer view.
Back to Autozone for some hose. The only thing they had that was close to the ID of the original hose was some fuel line. They found a little piece about 6" long in the back and just gave it to me. Thanks AZ man. Fuel line is quite a bit stiffer than vacuum line, so I put a tiny bit of silicone grease in each end with a q-tip to help it slip together. While I was there I replaced the 2" piece on the other side of the tee as well.
Here's a after-fix photo
I had noticed a few months ago that the engine was idling rough. I also noticed the gas mileage was slowly decreasing, the left front hub would occasionally clatter and the HVAC air would not change from defrost to the vents until 5-7 minutes after the vent button was pressed. I suspected that there was a vacuum leak somewhere, but hadn't really had the time to investigate. I'm glad the SES light forced me to give it some attention because it runs so much smoother and has more power now that it's fixed. And, no more SES light!
Hopefully this will be helpful to anyone having vacuum challenges too.
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