First I just want to say thanks. I have been searching the web for hours and hours, days and days, and this site has given me the most useful info for my problem.

However, I still have not reached a complete fix yet. And while I am still in the process of diagnosing and getting the truck running, I figured I would start this thread to see if there is anything else I am missing and so that if someone else has the same issue they have something specific to look at.

I have my issue's narrowed down, but I'll give a little background. Stock truck, I forget the actual millage but its around 140,000. Its been a good truck. Babied really. I drive a work vehicle so it does not get used much. However, the last time I drove it after it would reach operating temps there would be a sudden loss of power. Almost as if it was going to die. It never did, and eventually I got used to the problem. Bad thing to do, I know...

Stepping on the gas did not do anything really, so I learned to just leave it alone and it would just suddenly pick right back up. It was almost as if a switch was going on/off. I really cannot say how long it would last, maybe a minute, maybe more. What was interesting is that just as soon as it would pick back up the check engine light would come on, then after a few seconds go back off. Almost like it was a little "slow" in seeing that the truck was having an issue.

Well, then from time to time it would be hard to start. Not always, maybe every 5th time or so. So, me not using it much, I lent it out a while back. My inlaws took it into town and stopped to eat. They came back out and the truck started, then stopped, and now it has yet to even try to sputter one bit. Completely dead.

I finally got around to looking into it this weekend. I found that I do have spark, and the fuel rail does show some pressure. I understand that I need to measure the pressure, but to eliminate a fuel issue for the time being I bought some starting fluid to try it. It would not even cough with starting fluid.

As far as the spark goes, I tested it at the distributor with a tester and at the block with a used plug. It shows good spark. So my mind is wondering why it will not even begin to start. It acts like there is no fuel, and no spark. But I know it has both. I pulled and replaced the plugs after I found that several of them had insulators cracked. The plugs I pulled showed signs of fuel getting delivered to the cylinder. But then again, I am not overly concerned(unless I am missing something) about the fuel issue as it would not sputter with the starting fluid.

So it leaves me at a loss of compression or spark. I cannot see how compression would have been lost so quickly and so suddenly, without warning, as to keep it from even trying to start. Educate me if I am wrong. So that tells me that it is pretty much narrowed down to spark. I do not have a timing light, so I cannot say much for timing. But my curiosity is if the TFI could be causing a timing issue? It is mounted to the fender on my truck. I plan on taking it in for a test tomorrow.

The other thing I am guessing is the PIP, but I would think that if it is out then I would not have spark at all? I did read where it can from time to time get the metal hall effect blades magnetized and it can cause some erratic signals to the TFI? I thought about trying to demagnetize it. In the end, I am not opposed to replacing the whole distributor, but wanted to do the easier stuff first.

So I will test fuel pressure soon, and have the TFI tested. Anything else? My main question revolves around why I do have 'some' spark, and (having sprayed starting fluid) some fuel, why I would not have any hint of the truck trying to start. It seems almost like the timing is way off and the spark is trying to ignite while a valve is open or something? I just cannot see how there is no firing going on inside the cylinders with fuel and 'some' spark. I almost forgot, I took out the SPOUT plug and it seemed to try and crank at a different rate. Had a slightly different sound is the best way to describe it. Still not even a hiccup though.

Thoughts? Thanks.

 

The first two things I would check are fuel pressure and static timing. They're both easy enough to check and will help you track down your problem.

 

So I got to thinking. I pulled the TFI and am going to have it checked. At the same time I went ahead and did a KOEO test with my tester. Wish I would have realized I had this tester, I was under the assumption that my truck was a OBD-II. Anyways, no codes. But that's to be expected, I guess, seeing how I had removed my battery a few weeks ago to charge it(my truck is in a location not near any power).

However, through this and talking with a guy at work I realized something. When the truck first started doing the lack of power thing the check engine light would never come on until the truck had resumed normal conditions. So it makes me wonder if the check engine light was not coming on due to a downstream sensor on the exhaust somewhere.

The condition I was feeling was almost as if the fuel injectors were going haywire and dumping way too much fuel in the truck. It was the same 'feel' as when I punch my four wheeler throttle and its too much for the little engine to handle. Just real boggy. In fact, its the exact same feeling. When it first started happening I remember thinking the truck was dying and I would step on the gas petal. Nothing would happen. Not to mention that for a while before this the truck seemed to be running quite rich. You could smell gas in the exhaust pretty good.

I also noticed yesterday, when I tried cranking again, that I was smelling gas. Almost, but not quite as strong, as when you flood a lawnmower engine while trying to start it. I am assuming that the smell might not be as strong because I am a lot farther away from it than with a lawn mower.

It should also be noted, that Saturday when I was first starting to test things, I did check my injectors. I had a steady 12 volts to them and then I kept the meter on them while another person cranked the truck. I had the meter leads between the two posts and while the truck cranked the meter would jump around. So they are getting pulses. I guess if I wanted to get really professional I would get some noid lights, but it seems that the injectors are working regardless.

So does this add anything to the equation for someone? Would love to hear some more thoughts.

 

Starting to sound more like the PIP huh?

 

Well after some digging seems that I need to stick to my original plan of checking the fuel pressure. It looks like a LOT of my symptoms could be coming from a bad pressure regulator.

 

Dumb question but would the coolant temp sensor possibly cause this? When mine went out, the truck had to dump fuel into the cylinder because it thought it was too hot, ran like chit, and smelled strong of unburnt gasoline. Just a thought.

 

Interestingly enough I believe that my coolant temp sensor was in fact not working. Actually, I know it was not for a while, if I am looking at the right sensor. During the initial search of the engine I looked for loose wires and such. There is a sensor right above the water pump(if memory serves me), has two wires, and one was completely cut in two. Not sure how it happened, but I spliced them back together and it did not help the engine start at all.

So maybe that was why I was having an issue with the truck running rich and might just be a side problem. The more I thought about it today, the less sense it made that too much fuel was my problem. If that was the case, and only the case, then I would think that after the truck had sat for a while it would at least cough or something when I tried to start it.

So I guess now my mind goes back to PIP sensor, unless its the TFI. I did not get around to getting that tested today, hope to get to it tomorrow. I did find the step by step testing of crank but no start thing. Testing PIP, TFI, Coil, etc. I will do that sometime this week, just need to get a led from radio shack.

 

Got the TFI checked. It passed with flying colors. Its an original Motorcraft one. I guess I should eventually buy another to stick in the truck for the time it eventually goes out the way everyone talks about it going out.

So, now I'd like some thoughts with this. I really thought I would get more discussion than I have. I know I threw a bunch out there, and really my goal is to just leave a paper trail for the next guy who comes along, but discussion would not be bad either.

I'll pick up a fuel pressure tester tomorrow. However, my mind is really leaning to the PIP sensor/distributor. Of course, I guess it could be the coil still right? I am wishing now I had spent a little more time in spark testing on Saturday. But I can say that I know I was getting some spark.

So here is a specific question I have. It is my understanding that the PIP sends a signal to the TFI, but also to the fuel injection computer. Does the fuel injection computer receive the signal directly from the PIP, or does it come from the TFI? If it is a dual signal that the PIP sends out, could it be sending out a signal to one, and not the other, or randomly in between?

Its hard for me to understand why I have some spark, but not get even the slightest sputter when I spray starting fluid in the intake.

All in all, I've got to keep my head on my shoulders and stay the course. Time is just the issue with me. And it does not help that the truck is a couple miles from the house. I'm going to see if someone can give me a tow home tomorrow. That will allow me to work more on it. Maybe I can get the step by step ignition testing done tomorrow evening. Should at least get the fuel pressure tested.