So, the truck developed a new problem today. Here's the outline of the truck:
1989 F-150 extended cab. 5.8L, Jasper engine with 8K miles on it. New fuel tanks and pumps last year. Rear tank works fine, front pump runs, but is not pumping fuel (wiring problem?).
I found and fixed an alternator problem a couple months ago. The alt was not charging the battery - found that there was a chewed wire. So all has been pretty good for a couple months.
Anyhow, today, I was nacking down the driveway to load up the rest of the debris to go to the dump tomorrow. Startup fine. Backing down the drive, no accelerator, just under idle power. All at once, idle becomes really rough, and the engine quits. I can start it, but it is difficult to keep it running. Timing check: OK. I don't see anything obviously out of place. It seems like a really bad vacuum leak. Strong smell of gas. Smoke from rear of engine.
So, I check the PCV valve. If I pull the upper hose off, it will run, although it's pretty rough. Plug it back in and it shuts off.
So, is it the pcv valve? it seems to let airflow through. I don't know much about the pcv valve operation and symptoms related to its' demise.
Thoughts?

 

Plug the PCV valve back in, start the truck, and pull the oil dipstick, and check if you've got pressure coming out of that tube. If you do, Yes, you have PCV problem.

 

I was at the auto parts store this morning for something else, and went ahead and got the pcv vale. Replaced it on the truck. No change. Is there something else about this system that I should understand? I have always been under the impression that the pcv system was not *all that* important to the engine operation.
I will try the dipstick test today when I get a chance.

 

Does the old PCV valve rattle when you shake it?

 

Yes. But I went ahead and replaced it. For 3 bucks, I figured it couldn't hurt.

It was so strange. Idling normal one second, then rough to the point of it shutting off. Like a big vacuum leak started, all of a sudden.

 

Oh, rattling isn't definitive, but generally, if it rattles when you shake it, its fine. It never *hurts* to replace it though, for the $3, if there's any question.

 

Yeah, I had always heard that 'if it rattles, it's good', but reading here yesterday, I found a couple of folks saying that that isn't always the case.
I did try to suck air through it, and I could, but, again, for 3 bucks...
Could it be plugged up at the valve cover end?

If I remove the upper hose from the valve, the truck will run, but it's very rough. And it generates quite a bit of smoke - looks like oil smoke.

Is this something that could sourced at the distributor cap or rotor? I replaced the distributor, cap, rotor, coil with MSD parts last summer and it has run good since.

 

Pulling the breather hose off the other valve cover and making sure it isn't blocked is a good idea. An engine with 8K on a fresh rebuild, if the rebuild is worth a damn at all, shouldn't have any blowby yet.

 

Yeah, the Jasper engine came highly recommended, but in the first year, I had three oil leaks (all under warranty), and I got a little frustrated with that. But, like you say, 8K on an engine is like new.
Especially since the original engine it replaced had nearly 250K of pretty hard miles. (At least the 130K of that on my watch were 'working truck' miles).
If the PCV system were clogged, could that cause other seals to blow out?

 

Yes, yes it would.

 

Uh, oh, not liking the sound of that.

 

fuel pressure? codes?

 

Haven't got that far yet. Might be able to get to it today, more likely tomorrow.

 

Codes blink as follows:
1-23-23-1-1-1-1-1
then nothing

Code 23 - Throttle sensor out of range or throttle set too high – TPS.

So, I replaced the TPS. Now, it will start, and run, but as soon as it starts, it runs up to around 3K rpms. Then it rises slowly to around 3500, then eases back to 3000, then back up and back down.
Too high for me to let it go for long.

Thoughts?

 

What else could be involved here?