2 Cylinders missing
Thread Starter
|
Posting Guru
Joined: Oct 2004
Posts: 1,229
Likes: 0
2 Cylinders missing
My 1985 F-150 has a 5.8L 4v H.O. I noticed that i seemed to be missing on two cyclinders. I can take off the plug wires, and nothing changes. I have checked the plugs, wires, and compression, and all seem to be fine. I took off the valve cover, and everything seems to move fine. The cylinders that are missing are #3 and #8. Does anybody have any idea what else could be the problem.
Thanks
Thanks
Thread Starter
|
Posting Guru
Joined: Oct 2004
Posts: 1,229
Likes: 0
It shoots flames while its cold. It stays on fast idle for a little while when i pull up to stop signs and stuff. But if i shut it off then start it again, it idles normal. probley just the carb sticking alittle. Lately though it has been dieing while i stop in drive or reverse. mabey it has loosened up, and now idles too low. Other than that it runs good. exept for the backfiring and missing.
Trending Topics
Thread Starter
|
Posting Guru
Joined: Oct 2004
Posts: 1,229
Likes: 0
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 Starter
|
Posting Guru
Joined: Oct 2004
Posts: 1,229
Likes: 0
That could be the problem, I was already going to check my brake booster today when i got home. Now i will do a thorough search of all the vacuum lines.
What is an intake runner though?
What is an intake runner though?
Last edited by jpjahn; Oct 26, 2004 at 01:02 PM.
Elder User
Joined: Oct 2004
Posts: 984
Likes: 0
From: Winnipeg, Manitoba
Your vacuum booster is likely ok, unless you feel your brake pedal fall to the bottom while holding it down at a red light. Intake manifolds use runners to deliver the fuel/air mixture from the carb to the cylinder. Could be you need to replace the carb base gasket, or a vacuum line or two, or possibly even the intake gasket. You may find buying an entire gasket kit cheaper than just buying the individual gaskets required. You'll need an intake gasket and valve cover gaskets for sure, may as well do the timing cover while you're at it. If you can, grab a vacuum gauge and attach it to an available port on the intake manifold itself. (Look for a capped vacuum source preferrably, rather than plugging off an existing line and using it's connection.) Then post back with your findings. You'll be looking for needle bounce, and the actual vacuum reading as well. If the needle bounces when the said cylinders miss, chances are you could even have weak valve springs, or a cam lobe that has worn off, worn push rod, etc. Let us know before throwing money at a potential problem that may or may not exist.
Thread Starter
|
Posting Guru
Joined: Oct 2004
Posts: 1,229
Likes: 0
Well, I bought the intake manifold gasket, and the valve cover gaskets, and the gaskets for the carb. When I had the carb off, I decided to inspect it. I have a crack on the base of the carb. It seems that somebody decided to tighten down the nuts too tight, so the base is alittle warped as well. I took off the metal guard that is under the carb so i could test for leaks better. Then i reinstalled the carb without taking off the manifold or valve covers. I also checked a couple of teh caps on the plugged vacuum lines. they were leaking slightly too. Also there is a little lever that I believe does something for the coolant on the drivers side of the intake manifold that was toast, and the diaphram thing behind the carb which i believe is something to do with the EGR is toast as well. So those lines are plugged now. I checked all the plugs now and every one of the cylinders affects it now.
Also the electric choke on the carb is dead. so my choke has been staying on for most of the time.
What would be a good carb to put on there? I want good economy but power too, so probley somethign in the middle as far as performance goes. The carburator is a stock holley carb currently.
Also the electric choke on the carb is dead. so my choke has been staying on for most of the time.
What would be a good carb to put on there? I want good economy but power too, so probley somethign in the middle as far as performance goes. The carburator is a stock holley carb currently.
Last edited by jpjahn; Oct 31, 2004 at 12:32 AM.
