crazy rpm
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#33
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Hey...I get a turn.
Maybe your MAP sensor has gone nuts, or the vacuum source to the MAP sensor is leaking.
The ECM uses the MAP sensor input to aid in calculating the following:
Maybe your MAP sensor has gone nuts, or the vacuum source to the MAP sensor is leaking.
The ECM uses the MAP sensor input to aid in calculating the following:
- Injector pulse-width (rich/lean)
- Spark-advance programs
- Shift-point strategies (certain automatic transmissions only)
- Idle speed
- Decel fuel shutoff
#34
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Still... from what I gathered in the OP's first post, the idle wasn't high, it was eratic. Sure, it would rev-up but he also mentioned it dropped to 700rpm. If the O2 is faulty or a wire is chafing and grounding out somewhere then the ECU would be trying to compensate with a more lean or rich ratio, right? Jkshavoc, were you giving it any gas in that video?
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No, it doesn't, and I should've re-read my post before hitting submit. I must've been thinking the MAP sensor- I was only on a couple of hours of sleep, so some crack may have helped. OP should check the grounds for the O2 and ECU/TCU as idle issues on a Renix are often from faulty grounds though.
Still... from what I gathered in the OP's first post, the idle wasn't high, it was eratic. Sure, it would rev-up but he also mentioned it dropped to 700rpm. If the O2 is faulty or a wire is chafing and grounding out somewhere then the ECU would be trying to compensate with a more lean or rich ratio, right? Jkshavoc, were you giving it any gas in that video?
Still... from what I gathered in the OP's first post, the idle wasn't high, it was eratic. Sure, it would rev-up but he also mentioned it dropped to 700rpm. If the O2 is faulty or a wire is chafing and grounding out somewhere then the ECU would be trying to compensate with a more lean or rich ratio, right? Jkshavoc, were you giving it any gas in that video?
yes i revved it a few times, but you can see how the rpm's are erratic and jump around. It sometimes stalls, when i took the video it wasn't that bad usually its worse. Thanks for the replies.
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Don't give up on your XJ just yet..... You'll get it.....
Did you spray a little carb cleaner around your engine bay? Its a good way to help find vacuum leaks.
I'm kinda leaning towards that its a combination of issues. Is your tps adjusted properly? Are you sure all your vacuum leaks have been addressed? How about your throttle body butterfly? How does your intake/ exhaust gasket look? What about your exhaust manifold itself?
Just throwing things out there. Good luck.
Did you spray a little carb cleaner around your engine bay? Its a good way to help find vacuum leaks.
I'm kinda leaning towards that its a combination of issues. Is your tps adjusted properly? Are you sure all your vacuum leaks have been addressed? How about your throttle body butterfly? How does your intake/ exhaust gasket look? What about your exhaust manifold itself?
Just throwing things out there. Good luck.
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Don't give up on your XJ just yet..... You'll get it.....
Did you spray a little carb cleaner around your engine bay? Its a good way to help find vacuum leaks.
I'm kinda leaning towards that its a combination of issues. Is your tps adjusted properly? Are you sure all your vacuum leaks have been addressed? How about your throttle body butterfly? How does your intake/ exhaust gasket look? What about your exhaust manifold itself?
Just throwing things out there. Good luck.
Did you spray a little carb cleaner around your engine bay? Its a good way to help find vacuum leaks.
I'm kinda leaning towards that its a combination of issues. Is your tps adjusted properly? Are you sure all your vacuum leaks have been addressed? How about your throttle body butterfly? How does your intake/ exhaust gasket look? What about your exhaust manifold itself?
Just throwing things out there. Good luck.
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