Rough idle, any suggestions?! (I did search)
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Rough idle, any suggestions?! (I did search)
Well now I am on to the famous and well known (But not so easily corrected) RX-7 Idle.
It idles at 750, but it's rough. It smoothens out as the RPMs go up, but I have only taken it to 2000RPM and it's still kinda rough. It also hesitates when I first get on the gas to raise the RPMs.
The BAC clicks in an unusual pattern. Jumpering the ISC and adjusting the BAC makes no difference. Unplugging the BAC does change the idle. Checked for vacuum leaks and none found. Where do I go from here. Compression was good a few months ago. Can't find my tester to check again because I know someone is going to say check compression. Anything I am overlooking? Why won't the BAC adjustment change anything? Timing DEAD on.
Here's a little background on the engine. Jspec S5 block, S4 sensors, Harness, Exhaust manifold and turbo, S5 UIM and LIM, S4 TB (If I remember correctly). No EGR, AWSV, ASV, Twin scroll (wired open), or Duty Solenoid. TID mod done, transistor in ECU replaced.
Every post that I have seen with the same problem, or very similar has the same response. Someone please help!
It idles at 750, but it's rough. It smoothens out as the RPMs go up, but I have only taken it to 2000RPM and it's still kinda rough. It also hesitates when I first get on the gas to raise the RPMs.
The BAC clicks in an unusual pattern. Jumpering the ISC and adjusting the BAC makes no difference. Unplugging the BAC does change the idle. Checked for vacuum leaks and none found. Where do I go from here. Compression was good a few months ago. Can't find my tester to check again because I know someone is going to say check compression. Anything I am overlooking? Why won't the BAC adjustment change anything? Timing DEAD on.
Here's a little background on the engine. Jspec S5 block, S4 sensors, Harness, Exhaust manifold and turbo, S5 UIM and LIM, S4 TB (If I remember correctly). No EGR, AWSV, ASV, Twin scroll (wired open), or Duty Solenoid. TID mod done, transistor in ECU replaced.
Every post that I have seen with the same problem, or very similar has the same response. Someone please help!
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83revival
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09-03-15 10:42 PM