Boss 260 rough idle - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars
Engine Specific Tech For all Ford Engines from Bigblocks to Clevelands.

LinkBack Thread Tools Display Modes
post #1 of 2 (permalink) Old 08-09-13, 09:09 PM Thread Starter
Registered User
malsusxr8's Avatar
Join Date: Aug 2013
Posts: 1
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

Sent from Free App
malsusxr8 is offline  
Sponsored Links
post #2 of 2 (permalink) Old 08-09-13, 10:31 PM Administrator
Big Block Ford's Avatar
Join Date: Apr 2001
Posts: 4,748
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.

71 429SCJ Mustang
Big Block Ford is offline  
Sponsored Links

  Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars > The Garage - Tech Forums > Engine Specific Tech
Gear in this thread - Powered by O'Reilly Auto Parts

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome