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post #1 of 2 (permalink) Old 08-09-13, 08:09 PM Thread Starter
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Boss 260 rough idle

Hi there guys and gals....
I own a 2003 BA XR8 Falcon, when the engine is idling once warm is very low (around 500rpm). I have had it checked out at work, they have said that passenger side cylinder bank is down on compression (1 cyl is at 90psi and the other 3 are at 100psi), they aside that have tested the coils and said they appear to be fine. They did however find that 1 spark plug from that bank wasn't firing properly.... I know the Boss motors are known for PCV hose issues, I've checked mine and all is ok in that respect.... I've heard rumors of valves and valve springs getting stuck, has anyone got any ideas on what I should do from here.....?? When the engine is cold, idles perfectly. When the engine is under load it runs fine. I have also been told from work that the engine is running rich.... Please help with any info ya can give me as I'd like to get these issues sorted out ASAP. Cheers people'sImageUploadedByAG Free1376104189.917034.jpg

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post #2 of 2 (permalink) Old 08-09-13, 09:31 PM Administrator
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Re: Boss 260 rough idle


All those compressions sound low to me. This could be caused by a number of things but seems a bit funny that all 4 on that bank are low. What were the numbers on the other bank.
I have heard of some valve issues but its not that common really.

The richness could cause the bad running when hot so couid be worth tracking what that issue is. Maybe the O2 sensors could be the problem.

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