Laundry list of little dumb problems

[curtis73]

94 B4000 4x4/M5OD 104k miles.

I have a bunch of dumb stuff that is going to require taking the Fordzda to the shop. I've been working 70 hour weeks and I'm currently without garage space (and it's bloody cold here). I thought I'd run some of these problems by you folks in case you have ideas that I can pass along to my buddy at the shop to narrow down some diagnoses.

1. The truck has an intermittent no start/rough idle issue. It happened about 4 times this past summer, but each time I could get it to recover with some gentle throttle input. Then this past August it let me sit hardcore. Hot day, went in to a restaurant for a meal, came out, and it would start but idle really rough at 350 rpms. Each successive start it would run rougher and die sooner. Under the hood I checked the obvious stuff. The first thing I suspected was fuel pump. When I pressed the Schrader valve on the fuel rail, I got vapor. Yes. Vapor for about one second, then fuel. Got back in and cycled the key a few times, still crank/no start. Re-tested for fuel at the valve and had liquid fuel. Relieved all the pressure from the valve, (that was a mess) cycled the key, checked the valve again and had liquid pressure. No idea how much, but there was fuel. No start. I towed it to my shop where of course it magically ran perfectly the next morning. I started carrying my fuel pressure gauge in case it happened again. It happened again tonight. Drove 20 miles with no issues, stopped at the store for a 6-pack, came out, rough idle and died. Tried again, same thing. I popped the hood and put my pressure gauge on, turned the key, the gauge popped up to [couldn't see] pressure... and started and ran fine, so whatever the problem was I may have missed it. All of the times it happened before it was summer and hot. Tonight it is 21F. I checked for fuel in the vacuum line from the FPR and found none. I also pulled the IAC and it looks recent and clean (but doesn't guarantee it's working right). I pulled the intake bellows and the TB doesn't look nasty; just a few traces of junk.
2. Possibly related; 16 mpg down from a normal 18 mpg, but that could be winter blend fuel.
3. Also possibly related, intermittent misfire that is very minor. I can tell at a stop because I can feel a little shake in the truck and the shifter has a little shake in my hand. Most people wouldn't notice, but I'm a gearhead. This misfire is more often happening than not. When it's not happening, it feels like SDS (sudden Cadillac syndrome) and it accelerates better. It seems like for 15 minutes each week, the stars align and it runs like it's supposed to, but the rest of the time there is that teeny misfire and slightly down on power.
4. Steering is strange. It is loose, which could just be the steering box, but follow me on this: Let's say I'm getting on a highway with a 270-degree onramp. I enter the ramp and turn the wheel about 90 degrees. When I go to straighten out, it feels like the wheel is almost stuck at 90 degrees. As I go to return the wheel to straight, it feels like someone was under the hood holding the steering shaft until I started to reduce steering angle. U-joint in the steering shaft? Rag joint? Stuck valve in the box?
5. Other steering issue. Manual front hubs. If I have the hubs engaged but still in 2wd, the problem in #4 is more noticeable. Things like slow parking lot turns I can feel the steering kick back a bit as I return the wheel to center. It is almost the same feeling as turning while in 4wd, but the opposite. In 4wd, the steering kickback gets greater as you turn harder. In this case, it turns fine, but as you start to re-center the wheel, it kinda pulses back to center. Tire pressures are all correct.

Anyone have thoughts on these? They are all so intermittent that it's hard to nail them down, and even harder for a shop to figure them out unless they have it for 3 months to duplicate the problem. I consider myself to be a damn fine tech and used to run a chain of 13 shops, but I just don't have the time these days to dig into it. I'm hoping someone will have an idea of what they might be so my buddy can narrow his search.

 

[sgtsandman]

Not sure on the others but with the winter fuel and winter tires, I'm seeing about 17 +/- right now on the 2011 with a 4.0 SOHC. The misfire issue could be giving you a bit of a hit.

 

[stsalvage]

One thing I don't get to see but will soon when I leave calif is colder weather and a lot more rain. I know your not Mr money bags. But Maintenance Is a big one for any of these trucks. I'm just going to ask when was the last time you did a compression check on your engine.

Whe4n eas the PVC valve checked or cleaned or replaced what dod your Positive and ground cables look like when was the last time you cleaned around or sanded the metal where your grounds go when was the last time you changed your fuel filter or fuel pump. I be checking for a crack In the line if all your getting is Air or Vaper.

Lately, I've been on eBay buying up all the Lead battery cables that came from ford for the 4.0 1990--1994 I've found out if you change your positive cable and negative cable The trucks run so much better.

Most Shops tell me the Computer in are trucks Needs to see 12 volts all the time and it needs to see that ground. Always stay on top of your battery.

I take it you have a block warmer in your ranger If not that is half your problem there I own 1990--1994 ford rangers and ford explorers all of them have the 4.0 5 spedd

 

[curtis73]

I don't even have a block heater on my diesels. Even when I lived in Ontario, we didn't have block heaters, or if we did, nobody used them. Totally not needed in PA, and when this problem shows up it is always when the engine is at full operating temperature.

14.6v at the fuse block, battery terminals are squeaky clean. New battery last year, new negative terminal along with it. PCV wouldn't cause that much of a leak, especially since they tend to clog closed, not open. I could imagine EGR, but repeated... umm... "impact adjustments" didn't change anything, but still a possibility