catalitic converter??

my 94 2.3 has 250,000 miles and has been a really good truck. Just last week it started running really bad, like on 2or3 cyls. I could hear the exhaust just a
tiny bit louder than normal. Wants to die in neutral. Lifted the hood to take a look, and it seemed real hot, but not from the engine. Then a trip later, it ran perfect. Been doing this for 3-4 days now, makes no diff if its cold or warmed up. A buddy says its the cat. converter...... would that act like this, good then bad?

Check it for engine code/s with an OBD. Sounds like 02 sensors (before and after the cat) is sensing too lean or to rich fuel/air mixture. Your module tends to compensate for this. After 250K miles, it's time.

Pardon my ignorance, but whats an OBD and whats it going to set me back?

Also this truck, just tonite went from running perfect to bad, then good again, all min one trip.

It has a smell like hot metal, the engine is running at normal temp.

OBD is a diagnostic instrument whereby you can extract the trouble code. I believe that your truck uses the OBDI. Instead of buying the instrument which cost between $85-$400, just take your vehicle to a reputable and reliable mechanic and they will diagnose your vehicle for about $90.00. At that mileage you'll never know what they'll find. But as a fellow gramps we seem to run perfectly but then dtsrt feeling aches and pains then BOOM! the ol' ticker just couldn't handle the viagra. Cheers.

[QUOTE=gramps52]Pardon my ignorance, but whats an OBD and whats it going to set me back?


Do you have an AutoZone Parts store in your location??
(you have to give them your DL and Credit card to hold while using).

They will loan you a OBD to check your problem codes.
(and reset you vehicle computer)


From there you can work on the real issue.

Does it feel like all the exhaust is coming out of the exhause pipe??
Clogged???

Hope this helps.

I believe the only models AutoZone can scan are the OBDII models ... '96+ for Ford.

The earlier models can be scanned by unique scanners .... or most can be read with a voltmeter ....or by counting the blinks of the Check Engine Light (CEL) after a jumper wire is correctly installed underhood.

12Ounce is correct. Go here to access the trouble codes. (http://www.troublecodes.net/Ford/)

ok, update.....I had the cat. con. repl. a week ago Fri. The guys said it was running real rich, did a code read, told me one of the coils was bad. (showed me) Replaced that, replaced plugs and wires.
One of the mechs. at work suggested the muffler was plugged, replaced that too. Still runs good when cold, then bad when warmed up. Sometimes it will cough, then run good again, all at once.

BUT..... I think I may have solved it, tell me if I'm right. If a thermostat was stuck OPEN, (and the radiator fan is constantly turning as it does on these models,), the computer is seeing that the engine is NOT WARMING UP and the mixture remains RICH, dumping all that fuel into the cat. conv.

I did tell the wife last week, the thermostat needs to be changed cause the heater isnt blowing hot at all, the dash temp gauge barely moves off cold.

Does this sound like it could be the problem?

The fan has a temperature actuated clutch that controls its rpm. If the code indicated that the engine is running rich (172 or 174 I believe) several things could be the cause and the water temperature is one of them but among the likely suspects are the O2 sensors before and after the catcon. From what I know, the computer works on default setting until after the certain period of time and the engine reaches operating temperature. What seem to be happening is that after the computer is enabled one or several of the inputs is/are malfunctioning or inoperative, or the computer itself is malfunctioning. The coil problem should have been relevant whether the engine is hot or cold. Also, when the mechanic replaced the carcon, didn't he check the exhaust system at all, hmmm... strange.

Thanks for all the replies, its nice to know someone out there likes to help his fellow man. (or woman)
Went to Auto zone, (after calling around found one with the right OBD scanner) came up with ignition problems, EGR PROBLEMS. Took the egr off, the diafram (sp) was ok, opening and closing the way it should.
Im off the thermostat kick, ----by the way DONSOR, this animal DOESNT HAVE A FAN CLUTCH. and only one O2 sensor, its right in the exhaust manifold.
So today I started pulling plug wires off the coils, and the rear coil is not sending spark to #1 and #4 cyls. This is the coil I just replaced. It is also the secondary coil, which I think fires on the exhaust stroke. It checked out ok with the resistance check, and the resistance between #s 1 and 4 which fire at the same time.
Next is the ignition module, but Im not sure where it is, could it be almost directly under the clutch reservoir in the corner, to the right of the round electrical connector which comes from inside? About 1.5 x 6 " with a bunch of wires coming out the lower part?
Is it extremely expensive ?
Any thoughts on this latest discovery?

Gramps. I checked my Manual again for the '94 Ranger 2.3L and the drawing shows two sensors located one before and one after the catcon. The one after the catcon is easy to see but the one at the exhaust manifold may be a little harder to find. Regarding your fan, the drawing in the manual shows a fan clutch (viscuous control only) however, your vehicle may be equipped with an after market Hayden flex blade fan (blade pitch changes with engine RPM). Your computer module I believe is located under the dash about mid section over the drive shaft mound. By the way what were the code/s which showed up on the OBD?

223, 224, and one dealing with the EGR

Well I finally got it fixed...
After checking the timing belt, I switched the coils and found they were both good. So what controls the coils? well the IGNITION MODULE, of course!!!
took it off, (which on my set-up is NOT an easy task,) had it checked out at the local AUTO ZONE. No good. With the new one on, I now have no check engine light, and the thing runs like it should.....SUPER.
Who'd of thot the ign. mod. could cause it to run like that?


Anyway, THANKS to all of you out there who put in their 2-cents. I really appreciate it.
Gramps