Go Back   MustangForums.com > Ford Mustang Tech > 5.0L (1979-1995) Mustang
Sign in using an external account
Register Forgot Password?

5.0L (1979-1995) Mustang Technical discussions on 5.0 Liter Mustangs within. This does not include the 5.0 from the 2011 Mustang GT. That information is in the 2005-1011 section.
Sponsored by Weld Racing

Welcome to Mustang Forums!
Welcome to Mustang Forums.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

Good Compression and Spark, Misfire and ticking noise, won't idle

Thread Tools Search this Thread
Old 08-12-2013, 02:47 PM   #1
Join Date: Jul 2013
Vehicle: 67 Ford Mustang
Location: California
Posts: 2
twohandstech spencergreer twohandstech
Exclamation Good Compression and Spark, Misfire and ticking noise, won't idle

Here are the basics, please help if you can:
91 5.0/302 Roller HO in a Carburated 67 mustang

Ran fine for about 20 minutes on the way to the DMV, then all of a sudden is sounded garbled on one side and would not idle. I cranked down the idle screw just to get it to run at about 1100 rpm. When driving, it would lurch a little at times, and I had to put in Neutral at stop lights to give it gas until I was able to get it back home.

There is a definite ticking noise coming from either: valve cover, or I may have not tightened down the exhaust manifold well enough, and there is an exhaust leak. Not sure which it is.

Did a compression check on that side, and all four cylinders are at 120psi.

After the engine is hot, I put a piece of plastic on each of the exhaust pipes. #5 and #8 melted it immediately, while 6 & 7 were warm, but did nothing to the plastic.

Removing #6 & #7 spark wires also causes no change, which is why I believe 6 & 7 are misfiring.

I've got good spark. The number 6 plug was black and a little moist, so I put in a new one, but still having same issue.

I'm not sure how to verify that #6 and #7 are getting fuel, which is the last item to verify.

Is it possible that this is a bad head gasket, or valve seal, even though I'm getting good compression? Or maybe the lifter is loose, and the intake valve is not opening to allow fuel?

Your thoughts are great appreciated!
This ad is not displayed to registered or logged-in members.
Register your free account today and become a member on Mustang Forums!
twohandstech is offline   Reply With Quote
Old 08-12-2013, 02:47 PM
Ford Mustang

Paid Advertisement


compression, idle issues, misfire, ticking

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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 Off
Pingbacks are Off
Refbacks are Off

Forum Jump


Featured Sponsors
Vendor Directory
New Sponsors
All times are GMT -5. The time now is 02:27 PM.

© Internet Brands, Inc.

This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. Ford® is a registered trademark of the Ford Motor Company
Emails Backup