check engine light after low fuel

[Mike05]

The check engine light came on in my 1996 Ford Ranger after I foolishly let it nearly run out of fuel. Is this something I'm going to need to take to a mechanic to fix, or is the light likely to go out on its own after a few startings now that the tank is full? (I've started it four times since, and the light remains.) Is there reason to think I'm doing my engine damage driving it? I've been told that disconnecting the battery can reset the computer in these cases--and I've also heard that disconnecting the battery doesn't solve anything on modern vehicles. Can anyone lend some expertise?

[fordman123]

Disconnecting the battery is an option.
The PCM monitors all sorts of things like fuel pressure and resistance in the fuel sender. It could be merely coincidence or there could be a problem. You will not damage the engine by driving it ..
Try disconnecting the battery for about five minutes to kill the
"keep alive memory" and then reconnect it.
If it was due to low fuel, then the light probably won't come back on.
If it comes back on, then you could try a mechanic to scan it and diagnose it further.

Good Luck!!

[flytomcats]

To all,
I have a 98 expedition EB, 77k, 5.4 motor. I was recently on a trip and got the check engine light, flashing, after going over Donner pass, 7,000ft or so. Had the wife look it up and it talked about possible misfire or something with the catlytic converter. The expi was running ok at the time I thought. After about 15 min the light would go off for a min or so and then would come back. Then it would go on steady. Of course the book says steady could be the gas cap not on tight, etc. After about 20 min I noticed the expi running rough and could feel the misfire, especially between 1500 and 2000 rpm. We were only three hrs into a 7 hour trip so we stopped in Sacramento and holed up for the night since it was Sun and no garages open. I did as much research on the web and armed myself with as much knowledge about the light. I want to say thanks to all who have posted before me, you really helped! In my research I found the following possibilities:

1)If the engine is running rough and smokey exhaust, fuel injector stuck open pouring too much gas in
2)Possible fuel filter dirty or problem with (?)fuel neck
3)Oxygen sensor, water or fuel dripping on it possibly messing with mixture(cold weather and water unfreezing or lots o'rain
4)EGR sensor(ExhaustGasRecirculation) or valve. Related is the DPFE or differential pressure sensor related to EGR operation
5)Fuel tank pressure sensor
6)water in the spark plug
7)a blown fuse
8)vacuum tube leak near intake manifold (we did find one soft PCV(positive crankcase ventilation) tube near it but don't think this was the cause.)
9)Idle Air Control valve or IAC
10)spark plug or spark plug wires or bad coil or coil pack
11)loose gas cap

After checking the OBD or on-board diagnostic code we got a P0304 which is #4 cylinder misfire, i.e. #10. Changed both the spark plug and the coil and all was well. Finished the last 500 miles without a hitch. In a lot of postings Autozone was talked about as being able to read your OBD codes for free. This turned out NOT to be the case at the one autozone I tried. The employee said they weren't allowed to read them in California. Not sure how wide spread this is but you supposedly can buy one on ebay for approx $45. I think the coil was the prob, the spark plug looked ok but the coils are advertised to 100k miles, 77k was close. I would recommend calling autozone or other parts stores or garages to see if they will read the code for free. The coil and plug were about 100 bucks plus an hour of labor and change for $184 total. Add in the 116 hotel bill and I got out of it pretty good. I hope this info helps someone else out, I've now read too many "check engine" light horror stories. BTW Bob's Auto Service in Elk Grove, CA did a great job, they specialize w/Ford.

[ntwperformance]

as a mechanic / shop owner i would have to advise not to take it to the zone for diagnostic if you you do ask the person what kind of training he has just reading codes can be very misleading you can spend alot of unnecesary money.and i always read codes for free.have a code email me i will send you all the info i have .

[4beatg8]

My 96 ford Econline van did a similar thing. Light came on and we took to Autozone. Code was PO 401, EGR flow insuffient. Found out gas cap was loose, tightened it and reset the computer. Light stayed out for a little while and then came back on steady. Apparently there is another problem.

[DRW1000]

Originally Posted by 4beatg8

My 96 ford Econline van did a similar thing. Light came on and we took to Autozone. Code was PO 401, EGR flow insuffient. Found out gas cap was loose, tightened it and reset the computer. Light stayed out for a little while and then came back on steady. Apparently there is another problem.

Unfortunatly when one gets an engine code it simply tells them which sensor is giving an out of range value. It does not nessesarilly mean that that sensor is at fault.

[felixnow1]

Originally Posted by Mike05

The check engine light came on in my 1996 Ford Ranger after I foolishly let it nearly run out of fuel. Is this something I'm going to need to take to a mechanic to fix, or is the light likely to go out on its own after a few startings now that the tank is full? (I've started it four times since, and the light remains.) Is there reason to think I'm doing my engine damage driving it? I've been told that disconnecting the battery can reset the computer in these cases--and I've also heard that disconnecting the battery doesn't solve anything on modern vehicles. Can anyone lend some expertise?

I am having the same problem. My car was low on fuel, when refill my engine light came on. My vehicle was scanned. The code is p0401 which means egr has low or insufficient flow. Please send response

Thank you :evillol:

[felixnow1]

Originally Posted by ntwperformance

as a mechanic / shop owner i would have to advise not to take it to the zone for diagnostic if you you do ask the person what kind of training he has just reading codes can be very misleading you can spend alot of unnecesary money.and i always read codes for free.have a code email me i will send you all the info i have .

I have a ck engine light, when my vehicle almost ran out of gas. 1996 Toyota Carolla with 110,000 miles. Was scanned and showed a code of p0401. Low egr flow or insufficient. I replaced the egr value, map sensor, front and rear oxygen senor, complete tune up, stll light came on. Please help1