Compression test questions
Thread Starter
|
Elder User
Joined: Oct 2008
Posts: 708
Likes: 1
Compression test questions
I've done compression tests before but I've always just pulled one plug at a time then replaced them when moving on to the next cylinder. I'm wondering if warming up the engine, then pulling ALL the plugs, then replacing them one at a time after testing each cylinder will ruin the readings. I.E. so when testing the first cylinder the other 7 have no spark plugs in, and by the time I'm testing the last cylinder the other 7 all have their spark plugs in. This obviously creates huge vacuum leaks when those cylinder's intake valves are open, I'm just wondering if this matters. If it's necessary or not to have the other cylinders sealed up while testing compression.
Thread Starter
|
Elder User
Joined: Oct 2008
Posts: 708
Likes: 1
So that means I've been doing it wrong up until now. Sounds about right
Thanks for the replies.
Senior User
Joined: Oct 2007
Posts: 127
Likes: 0
From: three rivers, ma
Trending Topics
Thread Starter
|
Elder User
Joined: Oct 2008
Posts: 708
Likes: 1
Thanks. That's the way I did it. Compression test came out good. 140 as a low and 160 as a high. Engine was cold and no oil was put in cylinders for a second test. I was happy enough with those numbers to not bother.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
Thread
Thread Starter
Forum
Replies
Last Post
1954wrecker
1948 - 1956 F1, F100 & Larger F-Series Trucks
20
Jun 27, 2018 09:16 PM
slimtim86
Y-Block V8 (239, 272, 292, 312, 317, 341, 368)
2
Aug 25, 2016 10:21 PM
rdweathers
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
6
Jan 3, 2013 07:48 PM
Boltgunner
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
17
Feb 6, 2006 10:58 PM
