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94 F150 4.9 Bad fuel replaced - wont run

Hello...... I am the new guy and looking for some ideas on how to get old blue running again.....Dallas TX.


Warning…This is my first & a long post…… Truck has not been driven much in 5 years. The last two years only started and drove on the farm a few times, never very far. Prior to my current issue it has always ran perfect. Only has 100k miles on it and purchased it new – it is a California truck btw. Wouldn’t start about 8 months ago and my automotive savvy Buddy replaced the front tank fuel pump. Started immediately and ran great for a quick 20 miles then sat at idle for an hr and seemed fine when I turned it off. Sat a few weeks and the next time I started it ran like it was on 5 cylinders; crazy amounts of blue smoke. No power, could barley move it 50 feet. Sat a few months and I took out the new fuel pump and reached in the tank and grabbed something thicker than oil/varnish smell obviously (apparently Buddy had not paid attention). Dropped tank and cleaned about a gallon of sludge and 8 hrs later re-installed. I changed the inline fuel filter, blew air through the lines and hooked it up. It ran exactly the same, maybe 10 min then when hot I can’t keep it going, crazy blue smoke.
Unfortunately I like overlooking the obvious and have changed in order:
• Plugs
• Wires
• Injectors
• Cleaned all parts attached to intake.
Changed Oil and Filter – all other fluids new
• Vacuum lines
• EVP Valve
• Battery
• Throttle Position sensor
• Idle Air Control valve
In between each step (few days, weeks) I would start it to see if problem solved. When it was cold I could start it only. There was a loud valve lifter/sticking type noise that started about the 4-5 time/part I tried. But knowing it was fuel that started the problem I dismissed the noise for the time.

Then I found a diagram online about how the duel tank system works on this truck and beat myself up pretty good for a few days.
So now I have:
• Dropped rear tank
• Cleaned patched and re installed
• New fuel pump ect ect
• HEET in both tanks
• Seafoam
• New fuel
No fuel leaks
Gas caps are fine
Hose clamps are tight

Knowing the fuel in the rear tank was cleaner/new I turned key and primed a couple times switched and did the same on front tank. Pressed pressure relieve valve before manifold, a lot pressure and fuel smelt good-not the varnish smell/dark color that is stained into my skin head to toe.

Started up better but now I still have the loud valve noise and the longer it ran the more it went back to its original problem but no smoke until the end (only run 10-20 min and dies when hot) and I noticed a lot of moisture out the tail pipe for the first time.

It won’t run long enough to go and try and drive it. Don’t think its gas now.

I speculate that when I installed the new fuel pump 8 months ago and let it sit and idle and it sucked all that bad gas throughout the whole system it ran ok because it was hot. Once it cooled off it had gummed up or clogged something in the gas delivery, emissions, or air department and that’s why I started at the tank and went forward. I would love to go drive it but have only made it a mile with the pedal pegged and not moving very fast before it warmed up enough to die. However that was before I did the rear tank this weekend.

Do you think that I need to drop the front tank again because it’s been running off and on 20 min at a time (10 times) for a couple months while circulating from the contaminated rear tank?

Catalytic converter clogged?

Pressure regulator valve?

Vapor Canister need cleaned or replaced?

How do you like the seafoam in the motor oil for a short time? I didn’t put much but thought it would help with the valve noise.??

Kicker is I need this truck to drive on the regular and I ran out of time to have it finished a month ago…..No clue-frustrated and need to stick to building buildings and not automobiles.
 

O'Rattlecan

Redneck Prognosticator
26,687
797
Belton, MO
I hate to ask this, but I didn't see it mentioned.

Did you change the fuel filter? I bet it 'did its job' when it recirculated all that old gas.

Ryan
 
I believe that you have multiple problems. First of all I would insure that the fuel pressure is within specs at all times. Use a gauge to monitor it. Then I would check to make sure that the injectors are working ans flowing fuel. Check out the great information on oldfuelinjection.com but pay close attention to http://oldfuelinjection.com/?p=38 and the fuel injector filters. There is an injector cleaning procedure on the site.
 
I believe that you have multiple problems. First of all I would insure that the fuel pressure is within specs at all times. Use a gauge to monitor it. Then I would check to make sure that the injectors are working ans flowing fuel. Check out the great information on oldfuelinjection.com but pay close attention to http://oldfuelinjection.com/?p=38 and the fuel injector filters. There is an injector cleaning procedure on the site.

I will get a gauge and check tonight. I have not looked at link but did clean the injectors and replaced fuel filter after the front tank was replaced. Do I need to worry about the back tank not being cleaned until last week. I didn't use any gas out of the rear tank until replaced tank but obviously the vapor was circulating for the last few months I've been playing trial a d error....

Also, I read something about "limp mode" does this model have that option? Do I have to manually clear it? Could this be it?

Off to get a gauge and I will let you know what happens.......appreciate the direction.
 
94 F150 4.9 Bad fuel replaced - wont run Reply to Thread

PSI on both tanks= 50 and held.

Runs better before it warms up and progressively worse

First I removed break booster line and RPM + and smoothed out a bit. Reinstalled

Removed the throttle position sensor RPM increased and i left off

Removed idle air control valve - no change. reinstalled both and it idles rough.

Removed new ECP, valve on the throttle body side & engine RPm increased and smoothed out a bit. Left off

Removed break booster hose , throttle position sensor an it didn't die until I removed the idle air control valve........

cleaned out the vapor canister lines as well..............
 

dustybumpers

don't play well w others
3,291
188
In my own world
Are you saying you have gas in the canister?

If so, you have a bad check valve in one of your tanks, overfilling the other tank, and filling the vent line

Check your oil level, make sure it is not over filled, and smell the oil, make sure it don't smell like gas
 
Good catch dustybumpers! Forgot about the check valve in each tank. And the gas in the oil. I've seen that one before also. Saw one that wouldn't run at all with the crankcase breather hose connected to the intake. Had to keep that one vented to the open air.
 
Check valves looked questionable when I onstalled-rubber grommets shot. On my list today. Oil is good level and no gas smell.

50 psi on both tanks after last nights test.

I don't have fuel in the vapor canister.
 
don't know whether it still matches your truck or not but when mine only ran on lpg and not on gas it was the eec relais which had gone bad. if thats not it could be the eec itself or jumped timing, or ignition
 
94 F150 4.9 Bad fuel replaced - wont run Reply to Thread

PSI on both tanks= 50 and held.

Runs better before it warms up and progressively worse

Took out the plugs and cleaned them and re-installed , no 1 & 3 were a little loose and all of them fuel fouled. Started up good and ran for 10 min and going to re-test now. Loud valve noise is still present but it does idle better with clean plugs.

Got the INNOVA 3145 code reader today and performed the first & second KOEO test EEC-IV Systems. What i got was..........

111 = pass

10 = separation code

122c = TP sensor below min voltage - replace with a new TP sensor?

332c = insufficient EGR flow detected _ solution anyone?
 

O'Rattlecan

Redneck Prognosticator
26,687
797
Belton, MO
You need a throttle position sensor for SURE! It is trying to figure out how much air it is taking in, but it can't because that sensor is out of range. I would worry about the EGR only after you get a the TPS switched. It might be stuck closed but worse things have happened.

Ryan
 
Just a little late..... I broke the bolt off removing the EGR right after my post last night. Was going to clean it. So I tore it apart and desided to remove pressure regulater valve and it had a bunch a gunk it- dirt rust. So I got a new one, going to clean the injectors cuz it's easy from here and tap the bolt on intake ect ect. Found a vac line burnt too. So I'm hoping this will fix the problems. Only fear being the fix doesn't correct the valve noise issue and I have to remove it all again to get the valve cover off. But with 100k miles and no previous motor issues I'm guessing its not valve, rod ect ect. I did get the EGR sensor as well.
 
Can/should I put the battery in and pump gas through the manifold before I install injectors and regulator? Last time around I could not get the fuel line off at the manifold without damaging it. I have at least one set of every tool out there made to remove..... but didn't want to damage line or manifold continuing to force. But after seeing the gunk at the regulator I feel it should be purged/cleaned out.
 

O'Rattlecan

Redneck Prognosticator
26,687
797
Belton, MO
You mean the fuel rail that plugs into each injector? Gosh I just can't see that getting clogged. Either way, I guess you could try to pump gas through it before you plug the injectors back in. That's going to be very high pressure though, it's going to move a LOT of gas, so have a back up plan when the fuel goes flying.

Ryan
 
Thanks O'Rattlecan............More info......The tanks were both bad when removed (should have replaced with new tanks - 1st side tank I ordered online didn't fit & ended up throwing it away, ordered it off the OEM part # too.) I cleaned everything out real good but the top of the tanks still had a little rust I couldn't remove completely.

I ended up flushing the gas out of the rail last night into a towel by ignition on a few times. I reinstalled the rail with the newly cleaned injectors including new pressure regulator and checked & replaced all vac lines, had one 1/8 line cracked in two places.

Now removing that broken bolt in the aluminum intake has not worked out yet. I actually started small and worked up to the 5/16 + easy out and broke the tip off. I haven't found a bit out there yet that will core through it including left drill bits. I will try and find a easy out that is left tomorrow to mush the bolt out the back, that was what I wanted to do originally but couldn't find one over the weekend........ I'm guessing applying heat is too risky?

I will grab a new fuel filter tomorrow. Hope this round is easier. First time I had to remove side tank and cut filter apart to remove off the back fuel line. I ruined the insert/cage that goes in the fuel line but found the replacement easier than expected.

About now hauling this to a Mechanic seems like money in the bank!!
 

O'Rattlecan

Redneck Prognosticator
26,687
797
Belton, MO
Can you post a picture of the bolt you're struggling with? Is it a bolt that attaches the lower intake to the head, or is it something that secures the fuel rail to the intake?

Ryan
 

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