1994 Ford 5.8 Light Throttle Stumble FIXED

We made this video to hopefully help those with a light acceleration skip, stumble, stall, whatever you want to call it. If your Ford 5.8 with EFI is having this issue this may be worth looking into. I chased the problem and talked to several good, trusted mechanics trying to figure it out. Throwing parts at a problem is never the right way to go, even though I did throw a few in the mix that weren't called for just as a trial and error basis.
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Welcome to the American Tradesmen Channel! First of all, we appreciate you taking your time to check out our content. We put a lot of thought into our channel before we ever made a single video. You're not going to hear profanity on our channel. What you will hear is a little humor and a little how-to. There's literally no telling what we'll be doing, we dabble in a little of everything. We can guarantee you will see plenty of tractors, bulldozers, excavators, trucks, diesel stuff, welding, and repair videos. There's a wide array of equipment showcased, anything from John Deere, International, Farmall, Ford, Komatsu, and the list goes on. If this seems like stuff you're interested in, check us out! We would love to hear from you in the comments or over on our Facebook and Instagram pages. To keep up with the latest projects make sure to subscribe and click the notification bell. Hit the "Like" button and let KZbin know you're enjoying the content we produce. Those thumbs ups help other folks discover us and we appreciate it!

[@TintKing]

I really hope that this is my issue also! I was pretty blown away on how spot on my diagnosis adventure has been exactly the same as yours only thing I haven’t done that you have is the whole distributor. Some odd information I learned about these trucks along the way recently, if you’re brake light is burned out, missing, or cut than the ecm thinks you are on the brakes so it will precautionary things like defuel and not release torque converter and so on. Moral of the story i miss my chevy!

[@hjartland]

Had a transmission guys tell me my shifting issue was due to a burned out tail light. Thought he was nuts, but he was right.

[@cliftongunter3940]

Same exact situation with my 95 302. I have done exactly the same things you did trying to figure this out

[@donschaefer9442]

Hey tradesman. We had a few of those 5.8s that we used for snow plowing. We had to carry extra computers just to get through the season. Some would do a no start. Some would start up and shut right off. Love those OBS Fords.

[@drew18ism]

There was 420 likes when I seen this. 😊 Could be a sign. I’ll let ya know if it solves my acceleration issues ...

[@crslyrn]

Thanks for the repair advice. Dang "Brain Boxes" always tossing a wrench into things. That pup is really getting big. Take care. 🍻🍻

[@AmericanTradesmen]

Thanks buddy. Yeah, Charlie is busy growing right now. His dad was close to 100lbs, looks like he took after him

[@crslyrn]

@@AmericanTradesmen We've got a 3 year old German Shepherd & he's about 100 pounds.

[@donw8552]

Thank you, brother. I am having the same issue with a different vehicle. Good to know what fixed yours. 👍

[@davemoffa3714]

Having same issue 95 f-150 5.0 done everything you did got same results thank you for the info

[@israelflores4424]

AWESOME INFO...I HAVE DONE EVERYTHING YOU DID ON MY 1993 F250. REST ASSURE ILL BE CHECKING THAT NOW... THANKS

[@jhoeldionet2649]

Did it fix it?

[@Franknorman420]

I am having the same problem myself after replacing, plugs, wires, rotor, cap, map sensor, iac valve and some vacuum lines. I guess I’ll take the computer out and take a look at it, in the case of it being bad is there any easy way to tell what computer I have?

[@marshallbott6936]

I’ve heard that those capacitors could cause all sorts of weird drivability issues. I never considered that. On my truck it’s only on light throttle where it starts to misfire, buck, piss, kick whatever! Might run a test or two more then try testing capacitance on mine. Thanks!

[@adamsexton5371]

I think im having the same problem, runs fine for a bit then, then wants to stutter when im accelerating then idles crazy. Any ideas?

[@tonycombes9288]

Same here man did you find out the problem

[@chandlertaylor6477]

?

[@ricks3313]

Bad pip sensor

[@anothermealcastironchefftr6039]

I changed that out still bucking back fire only when is warmed up especially up hill climb

[@tracemcgee869]

did you find out issue having very similar issue now

[@jeremywillingham4126]

95’ Bronco 351w, i changed the computer awhile back when the fuel pump wouldn’t quit priming. And I replaced it with one out of another truck; bet I need another one again

[@philliplapkovitch311]

I did the exact same thing I have the same problem like throttle issue it will die sputter. And I did throw parts at it every sensor disconnected that pollution pump everything but the computer computer for it even put in a new distributor it's an old farm my daily vehicle got to have it on the road I love this truck even though it's rotting out falling apart 👍

[@dond7908]

I recently bought a 92 Ford F2 50 dual tank truck with a 5.8 motor. My issues are similar to yours in terms of bad speed stuttering or sputtering but only on the rear tank. If I take my front back selector switch on the dash and push it to the front tank and then immediately back to the rear tank it will clear the issue for a while before the same problem comes back. I don’t believe it’s a computer EEC issue based on what you stated in your video. Like you I’m trying to figure out what the hell is going on. I replace the fuse link the front back selector switch on the dash, new fuel pump new tank and still the same problem. Again only on the rear tank

[@AmericanTradesmen]

Please keep us posted on what you find, it will no doubt help someone else in the future. Thanks for watching and commenting!

[@dond7908]

I’m taking the truck back to the tech who I trust, the other thing I found out is is supposedly these trucks have bad grounds. So I am having them splice into the ground cable to the fuel pump as close as I can get it to the fuel pump wire ground, and re-grounded a 2nd time to the chassis. To me it’s the simplest way to complete the ground wire.

[@lupegalvan9993]

I've seen a YT video where a guy mentioned the same problem as you. He cleaned out the fuel tank selector valve itself said it fixed the problem.

[@dond7908]

Found the issue. The rear sending unit, the wiring below the new pump it self was atrocious. I put a new pump “assembly” which included the hardware and wiring for the sending unit, float etc, works perfect now

[@ReptarART]

I got a code 98 which is eec hopefully this solves my problem

[@JohnDoe-jk8yy]

Yep got same truck your stories sounds. Familiar

[@mendozaconsultation]

Question: We're your throttle body hoses are,on the left side in between them,their is a vacuum nipple that has a cap on it. On mine, I have the 93 E150 5.8l club wagon van, is the same. I'm Having iddle issues and changed out everything like you did and had was told, an internal vacuum leak that was supposed to had been done a year or so back but problem is back. When I go down from 2nd floor to 1st floor garage in my complex, the iddle drops to almost stall. Was told my fuel pump may be bad and it did go a few month's ago so I changed it out BUT, still have the problem. Any suggestions...

[@AmericanTradesmen]

Are you getting any trouble codes? Also, a vacuum leak typically causes a high idle, not low. I’d be interested to know what your fuel pressure is running at.

[@mendozaconsultation]

No codes. And getging fuel,just installed new fuel pump and I had the fuel PRESURE checked a while ago and it was good. I also checked that fuel presure valve inside the doghouse and it's squirting fule.

[@DanBridges-g8r]

How does anyone know they had the same issue when he didn't post video of the problem? I have run into this on almost every KZbin video I have searched!

[@allengross7116]

What about a lean fuel sensor right side? I already changed EGR and solenoid checks out working. Same engine same same year

[@jimmiealexander4988]

I hope so that sounds kind of similar to what's going on with my van

[@mikeemerson4284]

Yeah I'm going to have to do mine

[@dakotawilson3630]

My 94 Ford F150 5.0 l. It will do the same thing but it'll only do it when it rains or it's wet and moisty in the air. I've put new plugs, wires, cap, rotor bug, and coil pack it still does the same thing. I even checked the computer too it didn't fix the problem. I was also thinking about putting a whole distributor in. I don't know if this would cause the issue but I'm noticed on one side of the engine all the spark plugs would be really wet in a way but the other side would be plane dry.

[@AmericanTradesmen]

By chance did you open up the computer case? Mine had some moisture inside of it, plus with the location of the computer it’s fairly easy to get moisture in it.

[@pivotmaster9556]

fuel air ratio? my 94 was way too rich, wouldnt start and the ect sensor fixed it. I have this same stumble on low throttle but only in 3rd, is there another sensor to point to rich condition? like 02 sensor? or is this a trans problem. Ive got new caps in the computer

[@jordanatcheson3278]

Where did you get your computer from I got a 95 f250 with 351 e4od trans I literally have done everything you have done with trying to fix the exact problem you had. So I'd like to k ow where you got your computer from please.

[@AmericanTradesmen]

Mine came from Bumper to Bumper (Crow-Burlingame). Not sure where you’re located as to if that chain of stores may be in your area.

[@oldberry]

So…replace the computer? Or just the capacitors? I am in the middle of this run around with a 95 5.8. Definitely issues with grounds too.

[@AmericanTradesmen]

If you have the means to do so I would say you can just replace the capacitors.

[@mattwhite2725]

Good fix Andy.

[@AmericanTradesmen]

Thanks cuz

[@brandondavenport6892]

I have been chasing my tail on this for a while. Map, cap, wires, aic, tps, coil, fuel relay, codes, etc. My ecm board looks good, but I'm suspicious it's bad cause i fixed everything else! It stumbles and dies under light acceleration or idle but can throttle out, so i dont think it's a fuel problem.

[@tommybronco4443]

I’m having the same problem, I’ve done everything that you have and my ECM looks good as well but I’m about to try and find one and see if it fixes the problem, it is so annoying. Also does yours run really rich? Mine does.

[@brandondavenport6892]

@Tommy Bronco i replaced the brain and it still acts stupid. Im about to do some volt testing and if it dont work out i WILL be converting to carburetor. I like efi but my efi is defective, hard to trouble shoot, throws no codes. Im over it. My 89 has 2 fuel pumps and the one in the tank is 7psi carb pump. The one on the frame is high psi. So if i bypass the frame pump, i can run a carb with the tank pump. All i need is an intake, distributor/coil and a quadrajet and a bit of wire reduction. I am fking done with these parts they (auto parts store) sell me that break after 2 years and oem lasted 30 years! I dont think this 80s efi is fit for a daily driving water fording dirt jumping mud mobile.

[@tommybronco4443]

@@brandondavenport6892 damnit that sucks, I was hoping it would fix it and I hear you buddy same here.

[@UnderTheTuscanNun]

Got a gut feeling this is my issue as well. Have read a bunch of forums now saying those computers have issues. I’m thinking at 200,000 miles I should replace everything but might start with the ECM (think it’s called ECM for year 92).

[@tommybronco4443]

Where did you get your ECM from?

[@krislitschgi2873]

I have a 1994 Ford f250 XLT when I accelerate acts like it wants to bog down but when I let go of the gas and hit it again it's fine new air filter fuel filter plugs cap and it's still doing the same thing only when I accelerate it acts like it wants to bog down but then when I let go and hit it again it's fine I drive it everyday what do you think the problem is

[@vegarojasj21]

I have a 1995 F250 and it's doing the exact same thing. Took it to the mechanic but it's still boging down.

[@geth__commands_6300]

@@vegarojasj21 yep me too i will try to advance the 'total timing at 3000rpm" at higher increments to get more vacuum im having a drop in vacuum to zero as soon load is applied wont go over 70km thats inching to that speed

[@GuyinWY]

Glad you got it!

[@AmericanTradesmen]

Thanks buddy...it gave me a fit for a while. Hope you’re doing good, looking forward to another video on your old Ford tractor when you get a chance.

[@bigchris0886]

Did you by any chance have a misfire also? Or manifold popping to go with it? I'm about to run codes again and check fuel pressures... after throwing normal tuneup parts on a 94 302.

[@TOY_OSRS]

I have a 5.8l doing what urs is did you find the problem. I’m stumped on mine

[@bigchris0886]

@Creature Outdoors 5.0. Had clogged EGR , replaced 02 sensor*, also had a bad injector causing knock

[@TOY_OSRS]

@@bigchris0886 thanks man I just got done checking fuel pressure and timing I already have a new dizzy and wires and plugs I checked everything 100x the egr is my next project

[@bigchris0886]

@@TOY_OSRS I replaced a few other things also. But those were the culprits. Now I'm chasing vac lines for higher idles

[@my_name_is_chef4856]

Is there anyway to test the computer? Or do you just visually inspect the board? I mean I’d hate to spend the 200 bones for it and still have an issue. I bought a 97 250hd with the 5.8 it had a miss under load when I bought it so I did a basic tune up. The cap rotor plugs wires. Was running great for a couple days then the misfire returned. Now it misses at idle and under acceleration. Changed the icm and replaced all my vacuum lines, it seemed to make it worse again. I have no codes from the koeo test other than 111. Anyways, I’m tired of throwing parts at it. It’s got me thinking I should trade it for a pre 75

[@AmericanTradesmen]

In my case I was able to visibly see the issue as soon as I opened the case. I’m not a fan of firing the parts cannon at a problem either, and after MUCH online research I ran across a forum where this was mentioned. After everything I had done this was the only thing left to try. I hope you get yours straightened out!

[@sharktank7497]

I have same issue. Where did you get the new computer?

[@AmericanTradesmen]

@@sharktank7497 I purchased mine from Bumper to Bumper Auto Parts. I’m not sure who their supplier is though.

[@ProRidu24]

Got a 93 Ford F-150 with 5.8 out and it runs like garbage like makes the entire truck shake like it’s misfiring and any more then a sliver of petal will make it want to spit and spuder. Had a buddy say it was the computer but they cost a lot to just buy on a whim..

[@christianbelcourt279]

You can solder new capacitors on fairly easily, wish I would have thought to make a video when I did mine. I think I paid a few bucks for each capacitor.

[@zacharytruex1702]

Mine stalls when accelerating or when i turn the steering wheel

[@mendozaconsultation]

On your throttle Bobby between the upper and lower hoses, you have a red collor cap on the vacuum nipple there. What goes there...?

[@noahmartin7542]

I have 1990 351w and sounds like I’m on rumble strips after shifting into third at a soft acceleration but it is completely fine at a harder acceleration to speed up instead of maintain speed I’m stumped on it and am thinking I’m having the same problem you were

[@grezikpainting]

Could be a Tourqe converter going out

[@JordanSVT]

I have a '96 F-250 with a 351w and I've noticed it's been driving kind of strange for a little now. I'll notice some times when I'm just cruising along the throttle seems to stutter a little bit, it'll go vroom, vroom, vroom, while I'm just keeping my foot steady on the throttle. Also, some times when I'm going from a start I can hear the RPMs fall (I don't actually have a tach) but go back up like normal as I begin to accelerate more and some times at idle it just sounds so rough and it's very shakey. I don't think most of the problems would be noticeable if I couldn't hear them since the exhaust is straight piped and it doesn't always have these issues, just some times. The truck only has 134K miles on it so the motor should still run healthy as long as all the parts are working properly. But theres just so many different things that could be going out and I don't feel like throwing a bunch of parts at it.

[@AmericanTradesmen]

One easy way to tell is to pull the ECM, open the cover and look at the capacitors on the board. If the oil has or is starting to leak out of them that would be a strong indication you’ve found your problem. Do you have any trouble codes showing up?

[@JordanSVT]

@@AmericanTradesmen I haven't looked for any codes. But a few times while driving I'd have the check engine light pop up but then it would just go away. Very weird.

[@AmericanTradesmen]

@@JordanSVT I’m curious to know what codes you might have. Let me know what you find out on yours, I went through a lot to straighten mine out but I’m happy to say it’s still running strong. Happy New Years and thanks for the questions and feedback 👍

[@JordanSVT]

@@AmericanTradesmen I'll definitely try to take it somewhere to scan it. I appreciate your response. You've earned a new subscriber and Happy New Year!

[@Chris_f150_]

This also happens to mine but it’s rare when it does it did you ever find what was wrong with it?

[@smelsermic]

I'm curious about the solution. Did you remove the EEC/ECM (computer) and replace/repair the capacitors on the board or did you just buy a new computer? I'm also having this same issue, done the tune up and discovered someone had been in there before and mixed up wires #3,7 on the cap. That resolved the miss at idle, but didn't resolve the "at speed" miss/bucking.

[@AmericanTradesmen]

I purchased a new (reman) computer. I would image you had a pretty good miss with 2 plug wires mixed up.

[@smelsermic]

@@AmericanTradesmen yes, there was a big enough/consistent enough miss I knew there was something goofy. After fixing it I discovered the same problem you describe in your video. I thought it could be a plugged cat, but those usually inhibit flow to where it’s almost in-drivable. Still exploring options, but it’s not my truck and dad doesn’t want to put much time/money into it so I’m hesitant to try myself. I just want it out of my driveway.

[@AntiMaxer]

i replaced almost everything on my truck turn out the new distributor i put in was bad from the store so now i have a new engine bay and all it was the distributor being/ going bad

[@sorzarapidz5976]

Okay. So when you were driving it was it okay if you barely had your foot on your throttle and once you needed more it bogged out?

[@red182984]

I had that problem right before it went to a no start. The problem was the gear on the bottom of distributor came loose .

[@garylawson5230]

I have 94 F150 with the 5.0 and it sputters and take off and at a steady speed but idles just fine fuel mileage is off.

[@mako5387]

Ik this video is 3 years old but I have a 1989 F250 with the 351w in it. And I’ll just be driving then my truck will sputter and just shut off on me. I let it sit for a minute or two then she’ll start back up and run fine. I replaced the fuel filter twice. Just redid the fuel pump. Getting ready to do spark plugs now. And I have no idea why my truck keeps doing this

[@Gmoney-p9l]

Did you ever figure this out mine is a 94 f150 but breaks up so bad I can’t even get down the street

[@VAcreeper]

GSD life!!

[@bigred10ify]

What vss fix

[@thebear6751]

Ais sensor next to the throttle body

[@baylertolman9910]

My 7.5 does this

[@10minutesounds31]

Did you read the codes?

[@OliverKoolO]

I smell mine burning. Been scared it brake fulid but its not. Dam ecm and I know it.

[@alv.its_eden7795]

I need your help 🫤 my truck is treating me like shit