Addendum Post
Thread Starter
|
Senior User
Joined: Aug 2005
Posts: 123
Likes: 0
Addendum Post
Hey guys,
This is the 4th or 5th post from me regarding my 94 F250 5.8 with 94K miles. It's still missing while at idle or under throttle, I've replaced the fuel filter, plugs, wires, cap and rotor, coil, TPS, battery, fuel additive, left it a a garage for a week and they couldn't find the problem, they called it a "Ghost" we even took it to a reputable repair shop and had a fuel induction service, it's still spitting and dropping out. I have an INNOVA OBD1 code reader and no TDC's showed up. I've looked for chewed up wires from rodents etc. and I still can't figure this out. Thanks to all of you whom have responded in the past.
Jerry
This is the 4th or 5th post from me regarding my 94 F250 5.8 with 94K miles. It's still missing while at idle or under throttle, I've replaced the fuel filter, plugs, wires, cap and rotor, coil, TPS, battery, fuel additive, left it a a garage for a week and they couldn't find the problem, they called it a "Ghost" we even took it to a reputable repair shop and had a fuel induction service, it's still spitting and dropping out. I have an INNOVA OBD1 code reader and no TDC's showed up. I've looked for chewed up wires from rodents etc. and I still can't figure this out. Thanks to all of you whom have responded in the past.
Jerry
Cargo Master
Joined: Jun 2002
Posts: 2,033
Likes: 32
From: Aurora,Colorado
Is the idle speed correct when cold/hot?? If it is low-I would suggest cleaning the IAC.
Is the missing constant and continuous-or does it happen just monentarily?? Does it miss under WFT/WOT-with or without load??
I havent read your other posts. Have you done a compression test of the cylinders??
Is the missing constant and continuous-or does it happen just monentarily?? Does it miss under WFT/WOT-with or without load??
I havent read your other posts. Have you done a compression test of the cylinders??
Thread Starter
|
Senior User
Joined: Aug 2005
Posts: 123
Likes: 0
Iac
Thanks for responding phoneman, I did clean the IAC, it had some build up but I cleaned it the best I could. When I cold start the engine and it's running at high RPM's it doesn't miss a beat but once it kicks down is when it starts to miss, cough and sputter. It isn't all the time while running, it will come and go. I haven't done a compression test yet, that's the only thing I haven't done. I believe the INNOVA OBD1 code reader will perform a cylinder performance test. PS, It will spit and sputter while driving down the freeway too.
Jerry
Jerry
Thread Starter
|
Senior User
Joined: Aug 2005
Posts: 123
Likes: 0
Plugs
I think we put in Autolite plugs, I think I know where you're going with that question, one mechanic mentioned not using cheap plugs. Secondly, I thought about changing out the IAC valve, but thinking about it, would it affect even freeway driving and the same sysmptoms? Thanks for responding
Cargo Master
Joined: Jun 2002
Posts: 2,033
Likes: 32
From: Aurora,Colorado
Have you checked each fuel injector and made sure that all are clicking when the truck is idling. Does it seem like the truck is running on all cylinders--or may it be running on just 7 some of the time??
Is the idle speed normal?? Have you disconnected the IAC wires when the truck is idling-and if so-did the engine die? If not-there may be a vacuum leak.
Is the idle speed normal?? Have you disconnected the IAC wires when the truck is idling-and if so-did the engine die? If not-there may be a vacuum leak.
Post Fiend
Joined: May 2004
Posts: 11,289
Likes: 6
From: Lakewood, Ohio
Trending Topics
Thread Starter
|
Senior User
Joined: Aug 2005
Posts: 123
Likes: 0
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
New User
Joined: Dec 2005
Posts: 13
Likes: 0
The copper autolites work great. I would avoid using the more expensive platinum plugs.
I would put a vacuum gauge on it. You may have a vacuum leak. Also try pulling the codes by hand using the paperclip method. The scanner may or may not be picking up the codes. I don't trust them completely.
Have you cleaned out the throttle body? Checked the voltage on the TPS? My truck ran a lot smoother once I cleaned out the throttle body and put a new TPS on it.
I would put a vacuum gauge on it. You may have a vacuum leak. Also try pulling the codes by hand using the paperclip method. The scanner may or may not be picking up the codes. I don't trust them completely.
Have you cleaned out the throttle body? Checked the voltage on the TPS? My truck ran a lot smoother once I cleaned out the throttle body and put a new TPS on it.
Thread Starter
|
Senior User
Joined: Aug 2005
Posts: 123
Likes: 0
parts
Yes, I cleaned out the throttle body, replaced the TPS, cleaned the IAC etc. Still the same problem, sometimes when I'm lucky it will idle fine, then all of a sudden it starts to act up again. Very frustrating!!
Lead Driver
Joined: Aug 2006
Posts: 5,670
Likes: 12
From: Sand Lake, MI
Put a timing light on it, put the timing light pick up on each plug wire one at a time right at or as near the plug you can get it. Closer the better, get it down there.
Aim the light at the bottom of the hood or any dark area and watch the light flash while it runs, does the light flash at a steady rate on each plug wire or is it hit and miss?
If its hit and miss, is it on all cylinders, just one? not all of them but more then one?
Doing this simple easy test well help you narrow down the problem, if you find "hit and miss" flashes on any or all plug wires you have a spark problem, if all are steady flashes never missing a beat, then its a fuel problem.
How many miss will tell you something as well, only on one wire or two wires? Likely to just be the wire/s.
Hit and miss on all the wires, you have a bad distributor or spark control or both.
Badly worn bushings in a distributor will make a motor miss "hit and miss style" or all the time, may come and go too.
Aim the light at the bottom of the hood or any dark area and watch the light flash while it runs, does the light flash at a steady rate on each plug wire or is it hit and miss?
If its hit and miss, is it on all cylinders, just one? not all of them but more then one?
Doing this simple easy test well help you narrow down the problem, if you find "hit and miss" flashes on any or all plug wires you have a spark problem, if all are steady flashes never missing a beat, then its a fuel problem.
How many miss will tell you something as well, only on one wire or two wires? Likely to just be the wire/s.
Hit and miss on all the wires, you have a bad distributor or spark control or both.
Badly worn bushings in a distributor will make a motor miss "hit and miss style" or all the time, may come and go too.