smog pump amd the 2 check valves
Cruising
Joined: Apr 2019
Posts: 13
Likes: 2
From: Auburn IN
I had the check valve located behind the intake manifold go bad. It would be ok at startup but after driving for a while go out causing gas mileage to drop about 8 to 10 mpg. Motor acted like running on 5 cylinders and when stopped in traffic blue smoke(oil) poured out the exhaust. Changed both check valves (just to be safe) problem solved.
Drifting
Joined: Mar 2017
Posts: 1,486
Likes: 343
From: Long Island New York
^^^^ I think you had other issues and it was repaired when you took off the intake
My system was bad for over a year and all it did was pop codes very intermittent. I just tuned it out and plan on removing the system in the Winter
My system was bad for over a year and all it did was pop codes very intermittent. I just tuned it out and plan on removing the system in the Winter
Last edited by pjdbm; Jul 28, 2019 at 09:21 PM.
Cruising
Joined: Apr 2019
Posts: 13
Likes: 2
From: Auburn IN
The only code was for the check valve behind the intake. Most of the time it ran perfect. It only messed up during long trips. Three or four hundred miles at a time. Running 75 to 80 mph no problem, when you slowed down in town is when problems started. Trip from Austin TX to Sarasota it just kept getting worse till I changed the check valves in Sarasota. No problems since.
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Drifting
Joined: Feb 2008
Posts: 1,596
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From: Bahama North Carolina
The only code was for the check valve behind the intake. Most of the time it ran perfect. It only messed up during long trips. Three or four hundred miles at a time. Running 75 to 80 mph no problem, when you slowed down in town is when problems started. Trip from Austin TX to Sarasota it just kept getting worse till I changed the check valves in Sarasota. No problems since.
Cruising
Joined: Apr 2019
Posts: 13
Likes: 2
From: Auburn IN
There is one check valve on the right side of the motor, easy access. The second is between the intake and the cowl on the left side. The only way to change it is to remove the intake. I did the work myself which was not hard. Each check valve has its own code. Repair cost for parts was less than $100.00
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
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OH YES THERE IS a check valve located behind the manifold!!!
NOTE 1: The A.I.R. system operates at cold start up to help the CATs to come up to temp. It runs about 90-120 seconds.
It also operates for brief periods of time during part throttle driving when the PCM runs the system to verify that it is working correctly. The PCM expects to see a specific change is O2 Sensor signal during the time that the pump is running. If it doesn't (valve stuck shut of not opening fully) That is when you are getting the DTCs.
NOTE 2: The AIR system injects fresh air into the EXHAUST SYSTEM. Unless the system was sucking oil contaminated air from your air filter (that's where the pump gets it air supply) there is ZERO reason for the smoke and running badly and smoking. I don't think that happened.
NOTE 1: The A.I.R. system operates at cold start up to help the CATs to come up to temp. It runs about 90-120 seconds.
It also operates for brief periods of time during part throttle driving when the PCM runs the system to verify that it is working correctly. The PCM expects to see a specific change is O2 Sensor signal during the time that the pump is running. If it doesn't (valve stuck shut of not opening fully) That is when you are getting the DTCs.
NOTE 2: The AIR system injects fresh air into the EXHAUST SYSTEM. Unless the system was sucking oil contaminated air from your air filter (that's where the pump gets it air supply) there is ZERO reason for the smoke and running badly and smoking. I don't think that happened.
Cruising
Joined: Apr 2019
Posts: 13
Likes: 2
From: Auburn IN
OH YES THERE IS a check valve located behind the manifold!!!
NOTE 1: The A.I.R. system operates at cold start up to help the CATs to come up to temp. It runs about 90-120 seconds.
It also operates for brief periods of time during part throttle driving when the PCM runs the system to verify that it is working correctly. The PCM expects to see a specific change is O2 Sensor signal during the time that the pump is running. If it doesn't (valve stuck shut of not opening fully) That is when you are getting the DTCs.
NOTE 2: The AIR system injects fresh air into the EXHAUST SYSTEM. Unless the system was sucking oil contaminated air from your air filter (that's where the pump gets it air supply) there is ZERO reason for the smoke and running badly and smoking. I don't think that happened.
NOTE 1: The A.I.R. system operates at cold start up to help the CATs to come up to temp. It runs about 90-120 seconds.
It also operates for brief periods of time during part throttle driving when the PCM runs the system to verify that it is working correctly. The PCM expects to see a specific change is O2 Sensor signal during the time that the pump is running. If it doesn't (valve stuck shut of not opening fully) That is when you are getting the DTCs.
NOTE 2: The AIR system injects fresh air into the EXHAUST SYSTEM. Unless the system was sucking oil contaminated air from your air filter (that's where the pump gets it air supply) there is ZERO reason for the smoke and running badly and smoking. I don't think that happened.