Hi everyone. I have a 1995 f-150 with the 4.9L 6 cyl. It has approx. 220,000 miles on it, standard 5 speed transmission. For over a year now, i have experienced intermittent stalling problems. There is no rhyme or reason to it, happens at any speed (tho usually during acceleration), in any gear, at any temperature, and after different lengths of driving time. Sometimes it will go weeks without doing it, sometimes just an hour or so. It dies, then will crank but not start, then usually starts again after a few hours. When the problem occurs, there are usually a few short "jerks" just before dying. So far, i have replaced the fuel filter, the rotor, distributor cap, spark plugs, ignition coil, and ignition control module, and also have run a few gasoline additives through it that claimed to clean the injectors. I am just wondering if anyone else has experienced this, or even if anyone has any suggestions as to what to try next. Its been a great truck for me since i bought it in '98, though i have had to replace the timing gear a few times. I really can't afford to take it to a mechanic, but i can't afford to keep throwing parts at it either. Any suggestions or thoughts would be greatly appreciated, and thanks ahead of time!

 

It sounds like you covered the basics. Are you losing fuel pressure or is it possible that your fuel pump is going bad?

 

you are going to think I am nuts but I would check that rotor and cap again . The same exact thing happened to me out of no where my truck would stall and wouldnt start up and I found out that my MSD ignition module was frying my cap and rotor. So I removed the MSD and went back to stock and I havent had a problem since

 

I've been having the same problem with my 2004 F-150 Super Crew...5.4 Triton. I've replaced the fuel filter 2 times now....even though the truck only has 93,000 miles on it. I've had it in the shop 2 times a well and nothing shows up on code.

 

I am having the same problem as tobeintheshade. Although i have not replaced all of that stuff and my truck starts back up right away. Well, after a few extra cranks than a normal start. Except today. It took about 3 min to get it started back up.

 

Since at this point we don't know if it is a fuel or an electrical problem, we'll just throw a few possibilities in OK?
The suggestion of possibly the fuel pump is one of them. I have had more than once where the sock in the fuel tank gets so plugged with dirt that the pump can't pull fuel to send up to the engine. That is why sometimes after a period of time it will start again because the suction dropped and the junk fell off the sock and the pump was allowed to operate once more until the sock became plugged again. Unfortunately you have to drop the tank to verify this.

If you had access to a fuel pressure gauge set-up you could leave it connected and when the engine quit all you had to do was check the gauge right at that time and see if you had the correct pressure or not.
BUT, if you didn't, it could be an electrical connection to the fuel pump or possibly the fuel pump itself. I'm trying to get you to examine the problem thoroughly before you spend anymore $ unecessarily.
How about I stop here for now and let you digest some of this OK?
hanky

 

I have asked a few mechanics and some auto parts places and some of them have suggested it is the ignition control module. It looks like an easy thing to replace. mine is remote mounted. And my haynes repair book pretty much says unplug and put a new one in. But i've heard that there is more to it than that.

 

I have the same problem with my 89, 4.9, 5-spd. I removed the schreader valve, installed a tee with the valve on one end and a guage on the other and then started the engine. At idle I have about 49 psi and when I increase the rpm the pressure drops SLIGHTLY and the engine has a slight sputter. I noticed that at the exact moment of sputter the guage reads close to only 40 psi.Now I would like to know how I can determine which pump is the culprit, external or in-tank.

 

According to the specs I have your fuel press rdgs are within the right limits. Hot (slow) idle speed(RPM) fuel press should be 35-45 PSI. I would not just go and replace a fuel pump unless you are sure it is defective. Has anyone messed with the settings on the throttle body? This can give you the sputter/hesitation you seem to be having.

 

Thank you, I misunderstood that I need 50-60. By the way, as I increase rpm the pressure does not exceed 49 psi.
I do not know if the TB settings have been tampered with but I have owned the truck since new (unless the dealer did?). This (the sporatic shut-offs) all started a few yrs ago and after almost $2k in invoices (fuel pumps, filters, ICMs, caps, rotors, wires yes plural) I am now trying to diagnose this myself. I already solved the low voltage charging (see prev. thread) since I wanted to eliminate that as a possible cause. The truck progressively worsened untill it would only run for 20 min. after cold start and repeated starting decreased the run time untill it would not start at all. During this ordeal I installed a timing light on one plug and a test light on each side of the coil only to find that ign. run side of coil stays powered (as does the ecm relay) after stall and the other side does not. This all happens so fast (just like the key is turned off) it was difficult to determine what I lose first, fuel or spark. I searched this forum and decided that I would try the ICM from a parts truck I have. The truck started right up after the previous no-start and stayed running so I thought I had it only to have it die on the hwy 3 days later, truck started immediately and I continued.

Now I realize I only put in a used ICM but a new one up here is over $200 so I would really like to verify if it is fuel or spark. On a side note I am pretty sure the pump on the frame was never replaced but if you think my pressure is fine then I guess I will wait untill it dies again.

Sorry for the hijack tobeintheshade, but it sure sounds like you and I have very similar problems.