still sick-Frequency valve?
Discussion
My question
with the O2 sensor(lambda) disconnected from the ECU, is there a default setting , or a specific value where the cycle of the frequency valve should be? Should the valve be vibrating constantly?
When reading values with the meter should these values be fluctuating up and down. With O2 sensor out I had duty cycle readings holding steady at 50 , but only for a short while-then numbers jumped all over. How do i know if valve is operating properly.what readings should I expect to see with Lambda operating(closed loop)
Car is running Rich, still trying to isolate problem before returning to shop with 4 gas anylizer.
with the O2 sensor(lambda) disconnected from the ECU, is there a default setting , or a specific value where the cycle of the frequency valve should be? Should the valve be vibrating constantly?
When reading values with the meter should these values be fluctuating up and down. With O2 sensor out I had duty cycle readings holding steady at 50 , but only for a short while-then numbers jumped all over. How do i know if valve is operating properly.what readings should I expect to see with Lambda operating(closed loop)
Car is running Rich, still trying to isolate problem before returning to shop with 4 gas anylizer.
I am afraid that I cannot answer your questions with any real clarity... but...
Your frequency valve should be chirping costantly if it is opperating correctly. Only very short pauses should be audible and those are at no regular interval. The lambda sensor pretty much controls the frequency valve (however, it is also somewhat influenced by other relays etc - but not to the extent to cause the problem you describe), so typically one or the other of these going bad can cause syptoms at both ends.
Both of these "live" in harsh environments (high heat for the lamda sensor - constant running for the frequency valve) and therefore it is more likely that these will fail and cause problems long before the fuel dist. unit. When my car started cutting out and running lean, I replaced the Lambda sensor... then with no change I replaced the frequency valve. I was told by a trusted mechanic that I should have prob. just replaced them at the same time. At any rate, the car stopped running lean. Of note, the frequency valve was the primary issue. It was chirping, but when I put in the new one it was obvious that the old one was not chirping correctly or enough.
Good luck,
Drive topless!!!
Cameron
Your frequency valve should be chirping costantly if it is opperating correctly. Only very short pauses should be audible and those are at no regular interval. The lambda sensor pretty much controls the frequency valve (however, it is also somewhat influenced by other relays etc - but not to the extent to cause the problem you describe), so typically one or the other of these going bad can cause syptoms at both ends.
Both of these "live" in harsh environments (high heat for the lamda sensor - constant running for the frequency valve) and therefore it is more likely that these will fail and cause problems long before the fuel dist. unit. When my car started cutting out and running lean, I replaced the Lambda sensor... then with no change I replaced the frequency valve. I was told by a trusted mechanic that I should have prob. just replaced them at the same time. At any rate, the car stopped running lean. Of note, the frequency valve was the primary issue. It was chirping, but when I put in the new one it was obvious that the old one was not chirping correctly or enough.
Good luck,
Drive topless!!!
Cameron
Short of putting in another ECM... nope. You can check the resistance through the frequency valve, but it may read okay. The open and close function is obviously not getting tested and the ohms meter can read okay as the frequency valve is working part of the time. I do not think they ever totally fail... just enough to screw up your mixture. JAE sent me a new frequency valve in three days and I do not remember that it cost too much.
Of note, if you replace it - check the line that leads to the dist unit. It has a tendency to rub. It is in no way the cause of your problem (and was not mine), but it was nearly rubbed through on my car and would have sent fuel everywhere if had burst. I could not see this until I pulled it off the car! I put some hose around this line when I replaced it to provide some protection on the new line.
Drive topless!!!
Cameron
Of note, if you replace it - check the line that leads to the dist unit. It has a tendency to rub. It is in no way the cause of your problem (and was not mine), but it was nearly rubbed through on my car and would have sent fuel everywhere if had burst. I could not see this until I pulled it off the car! I put some hose around this line when I replaced it to provide some protection on the new line.
Drive topless!!!
Cameron
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