o/t Ford mechanics out there...

2003 Ranger 4.0, 154,000 miles. I don't put many miles on it anymore, and on my list to get to this summer is going through and replacing the plugs, wires, belts, etc.

Monday evening it was 95º, I setup some hoses watering the raspberries, did a quick run with the truck a mile away and back. Listened to the radio some more by the garden as I moved the hose and did some more putzing.

Started the truck back up and it stalled. That was unusual, and it was idling rough and I swear it smelled...faintly of rotten eggs, maybe rotten eggs and something else? It was a weird smell.

Going up my driveway it when I hit the small hill it started lurching and nearly-but-not-quite stalling -- like when you try to take off from a stop and don't realize you're in 3rd gear.

I turned around, went a 1/4 mile up the road...it lurched a little, but not bad. Above 2,000rpm or so it didn't seem too bad, but definitely acting like it didn't have much power.

No "Check Engine" light.

Tuesday morning I popped the hood. Has a Diehard battery, so I guess I did replace the battery along the way (I was thinking it was the original till I looked). I put on my battery charger, but it quickly reduced the charge it was giving it -- that indicated to me the battery was charged, since when I have a low battery the charger current stays up high for a while.

Come lunch time I started her up. Was hot still -- 97º. No smell, running smooth. Went a couple miles to town to get a grinder for lunch, stopped at the quickie mart, came home. Seemed fine the whole time.

So now I'm scratching my head with a problem I don't know how to reproduce, and didn't have a check engine light so I assume no computer codes. Need to travel on business on Friday so I think I'll be asking Mom if I can rent her Durango for the day...don't trust the Ranger right now till I get a reason she was acting up on Monday.

Plugged converter.

Allan

water in fuel?

soundguy

Sounds like it to me too, just hard to believe it would happen so quick.
Google FTE forums and click around until you find the group for your truck, usually some good info there, Dave

How would a converter unplug itself?

It doesn't.

Tempreature and expansion makes 'em act really, really weird early on. Gonna get worse and worse until it won't hardly even idle.

Gun it, you can "usually" hear 'em "hiss" at the exhaust.

Allan

As with anything mechanical, this diagnosis isn't set in concrete.

Just that his symptoms and the way it is acting are "screaming" converter.

Allan

Had it happen to me. Plugged converter.

Matt,

To test, just drop the exhaust pipe at the engine an inch or so and giver 'er a good road test. If the power is back and all is well, odds are that the converter is plugged.

Doesn't cost ya a dime and will let you know if this is the real culprit or not.

Don't know why, but the Fords are just a little cranky about that darned converter. More so than other makes, it seems to me.

Allan

Two things -

I agree it could be the converter - especially with the smell. When they break up on the inside they block the exhaust flow, shut the engine off and the peices fall to the bottem of the converter and suddenly its running fine - shake it up a bit (hard acceleration - rough road) and the peices block the exhaust flow again. If the converter is the issue you should be getting a code (but not nessarily a check engine light).

The other possible issue - partially clogged fuel filter acts the same way (without the egg smell) and you won't get a code or a check engine light. The electric fuel pump works harder trying to force fuel through the clogged filter and the engine runs rough as its starved for fuel. When the pump gets too hot it shuts down - it will restart a minute or two later but will shut down when it gets too hot again.

Allan - Have a 1994 Lincoln V-6 that is acting similar. Starts right up. Idles VERY erratically. Get RPMs above about 1500 and smooths out. Runs fine (to the ear) down the road but, as soon as it returns to idle goes to jumping all over (very rough). Would this also indicate a partially plugged converter? bob f.

I'll go against the tide here. I think it is a sticky Idle Air Control valve. You can take it off and clean it to see if it fixes the problem.

My 2000 Explorer 4.0 L has done that twice over the past 20,000 miles. It would barely idle and it would shudder when trying to drive it for the first mile or so. I have cleaned the valve twice but can't verify that it was the problem. Being an intermittant problem makes it hard to diagnose.

No Sir, not to my mind.

A plugged converter will come on gradually and the first symptom is usually a loss of power going down the road, climbing hills, etc. Then, they will get to dying. Addtionally, there is than darned "hissing" at the exhaust under acceleration and the smell of rotten eggs.

Your Lincoln sounds more like a "tuning" issue. Possibly needs a Power Flush? That sure wakes 'em up.

Allan

A 1994 Lincoln with a V6 is the 3.8L Essex engine a real POS - especially in early to mid 1990s (or possibly all the 1990s).


You might post your question here:

http://www.taurusclub.com/forum/index.php?s=a44e4513242bb0fe6fc9017efb90df4f&showforum=11

As it was also in the Taurus. There are a few guys that post here that really know their stuff.

A sticking IAC valve should throw a code - and should trip the check engine light. I'd go to Auto Zone and get a free code reading.

I wouldn't argue the converter idea...
I doubt it's the IAC motor though as that will only be a problem at idle. Once you're off anf running it shouldn't matter.
If it was a bad fuel pump or plugged filter it will be running lean. Running lean WILL throw a code, and will put the engine light on.
The only other though I'd have is simply a loose battery connection. Mabey it got loose. Mabey it got tight again. If it was loose enough that the computer lost it's settings, then it would have to 'relearn' itself, and it will misbehave for a while when it's relearning...
That's a long shot though. Sounds like a converter issue. I'm not sure about dropping the pipe handy the engine though. Those buggers have an O2 sensor handy the converter... so a lack of flow or abnormal flow over one sensor as opposed to the other 3 might set off some codes or other symptoms.

Rod

Matt, try this. www.batauto.com/Forums/ Scroll down to domestics, put your problem in there.
Hope it helps.

Looked up the catalytic converter in my Haynes manual, and it had a procedure to check the vacuum as part of confirming the diagnosis.

Ran up to Sears (about 12 miles each way), no problems coming or going.

Now, I just don't know where to hook it up! I took off a cover to see there was a test port, the only place I think I'd I know there is vacuum is the line to brake booster. Not sure if I'm supposed to take that line off and hook up the vacuum guage there?

If there is somewhere other then the brakes I should use, can someone give me some bearings where to look for it?

I also found something loose on the air system, I'll post that in a moment.

Allan - First I want to thank "dhermesc" for his post and suggestion.

Allan - What do you mean "Power Flush"? Is that something added to gasoline tank? oil? or what? Be happy to try what ever you suggest. Thanks! bob f.

When I had the hood popped, I noticed a tube going to the air intake was disconnected -- it was just there below the intake (I put it on top to take the picture). It popped right back in by hand.

Not sure if that's part of the problem, I don't even know what it is.

Run okay with that tube plugged back in the air intake ? Unmetered air bypassing MAF sensor .

That tube takes MAF-metered filted air to the engine crankcase (probably by way of a valve cover) to replace air drawn out by the PCV system.

By the looks of the inside of the tube, you've "dusted" the crankcase pretty well, and the engine has certainly drawn in lots of dirt though the open hole in the rubber air tube.

DANG!!!

Change the oil and filter NOW.

Yep, seems to run fine.

Well, ran fine on every errand today...

-- No codes on the computer.
-- Hooked up the vacuum guage to the brake vacuum line. 20psi at idle, 21-1/2psi at 2000rpm and holds steady.

If I'm reading the Haye's book right, that pressure should drop and/or I'd have to keep increasing throttle to maintain 2000rpm if the exhaust system was plugged.

Going off Alan's diagnosis, I'm still guessing I have a cat that is in the early stages of plugging up. $290 for an "exact fit" through RockAuto, I think I may live with it for a few weeks and see I can carry the vacuum gauge with me and catch the truck when it acts up next.

I suppose I could always order it and if I pull mine off and it looks clear return it.

Hi Bob,

A Power Flush is a pump powered outfit that washes the fuel system using external pressure. Must really scrub 'em up good, 'cause it makes one heck of a lot of difference.

Expensive machines, but most Ford dealers have 'em.

Allan

Your fine! ,,breather tube was causing your headaches . Give it few weeks . If your cat was plugged you would see very low vac under load . 2-3 inches .

looking at your pic i dont see a vacuum port on the manifold.any vac hose on the intake manifold will work.