Failed Emissions!
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From: Houston
Update:
Another emissions test. Another failure.
So now I've:
Tuned up.
Replaced 02 sensor.
Reconditioned injectors.
With the new injectors, the CO has gone haywire.
I'm thinking vacuum leaks. Anyone have a jumping-off spot for tracking down underhood vacuum leaks?
Here's how the numbers look:
Another emissions test. Another failure.
So now I've:Tuned up.
Replaced 02 sensor.
Reconditioned injectors.
With the new injectors, the CO has gone haywire.
I'm thinking vacuum leaks. Anyone have a jumping-off spot for tracking down underhood vacuum leaks?
Here's how the numbers look:
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From: Gone. On the Open Road
What in the Hell?
Check your most recent work over and items in the vicinity. Check the vacuum lines to the flappy, regulator, and dampeners. Make sure that the flappy line is connected to the 4-way from the check valve, and that the rest are connecter to the splitter next to the MAS. Then make sure that splitter is still connected to a single line running to the top of the throttle body. Make sure that connection is in place.
If you have a vacuum gauge you can check the lines at each of the items.
Check your most recent work over and items in the vicinity. Check the vacuum lines to the flappy, regulator, and dampeners. Make sure that the flappy line is connected to the 4-way from the check valve, and that the rest are connecter to the splitter next to the MAS. Then make sure that splitter is still connected to a single line running to the top of the throttle body. Make sure that connection is in place.
If you have a vacuum gauge you can check the lines at each of the items.
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From: Boulder Creek, CA
With an unlit propane torch in one hand and a halon extinguisher in the other, spray propane gas over all seams in the intake tract and all vac lines while the car is idling. Investigate any area where the presence of propane causes the idle speed to change. The best torch for the job is the type with the separate hose & handle that lets you keep the cylinder upright.
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From: We are there!(San Diego)
A vacuum leak would cause high HC and low CO, so I do not believe this to be your problem. You are failing on ALL pertinent gasses... I would give serious thought to replacing the cats. If your car still has the CO adjustment tubes, I would have the test station stick a probe into one of the tubes and then probe the tailpipe at the same time. I'm betting the readings will be about the same.
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From: Gone. On the Open Road
Originally Posted by Bill Swift
A vacuum leak would cause high HC and low CO, so I do not believe this to be your problem.
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From: Houston
What indeed? My fuel pressure flickers around 55 with the engine running.
Also, when I disconnect the vacuum hose to the front damper the idle doesn't change.
Also, when I disconnect the vacuum hose to the front damper the idle doesn't change.
Originally Posted by worf928
What if he's getting 55+ psi fuel pressure all the time because his dampeners and regulator are not hook to manifold vacuum?
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From: We are there!(San Diego)
Would have been nice to have known this little detail before... sure that will cause the kind of failure you are having. Does the line at the regulator actually have vacuum? It is not unusual for these to fail and allow fuel to be sucked into the vacuum line. This condition if left this way long enough can kill the cats, so that is still a remote possibility. Sounds like the regulator is your problem though.
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From: Gone. On the Open Road
I agree with Bill Swift. You should be seeing ~44 PSI at idle (IIRC) with ~55 PSI when you goose the throttle linkage and the dampeners and regulator lose vacuum. As Bill says, check vacuum on those lines at the regulator/dampener end and see if they have vacuum at idle and lose vacuum when the throttle plate opens. My bet is that you pulled off the vacuum line from the throttle body to the 5-way splitter when you were R&R-ing the balanced injectors. It is also possible that one or more of the vacuum lines has collapsed. Test those lines with the hand pump - they should not be able to hold a vacuum (when the motor is off.)
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From: Houston
I'm getting 40 cm Hg of vacuum at the fuel pressure regulator. Fuel pressure is about 55 at idle, dropping to about 50 when revved, and about 60 with the vacuum hose disconnected from the regulator.
No gas smell in the vacuum lines or from the vacuum port on the regulator.
Failed FPR???
No gas smell in the vacuum lines or from the vacuum port on the regulator.
Failed FPR???
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From: Houston
I'm getting 40 cm Hg of vacuum at the fuel pressure regulator. Fuel pressure is about 55 at idle, dropping to about 50 when revved, and about 60 with the vacuum hose disconnected from the regulator.
No gas smell in the vacuum lines or from the vacuum port on the regulator.
Failed FPR???
No gas smell in the vacuum lines or from the vacuum port on the regulator.
Failed FPR???
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From: Not close enough to VIR.
Originally Posted by MBMB
I'm getting 40 cm Hg of vacuum at the fuel pressure regulator. Fuel pressure is about 55 at idle, dropping to about 50 when revved, and about 60 with the vacuum hose disconnected from the regulator.
No gas smell in the vacuum lines or from the vacuum port on the regulator.
Failed FPR???
No gas smell in the vacuum lines or from the vacuum port on the regulator.
Failed FPR???
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From: Gone. On the Open Road
Mark, either your FP guage is way off, or you've got an extra ~10 PSI of fuel pressure.
Has the FP always been this high (since you started failing emissions tests?) Or did it start in the middle of this story?
Also, have you checked vacuum behavior to both (two) dampeners and the regulator?
Has the FP always been this high (since you started failing emissions tests?) Or did it start in the middle of this story?
Also, have you checked vacuum behavior to both (two) dampeners and the regulator?