Check engine light stays on

My check engine light stays on. I got the codes read and it said to change the oxygen sensors, so I did. Now it says to change the front oxygen sensor. I've had my computer reset several times and the light will stay off until I turn off and restart the vehicle. I even took the front sensor back and exchanged it for another one, because I thought the first sensor might be a bad one. I just had a tune up, and got a new exhaust system from front to back. Anyone have any suggestions?

Hey guys. Thanks so much for your input.I found a small crack at the connection to the ignition coil, and also a blown fuse under the hood that had something to do with the oxygn sensor. I changed these out and got it to pass inspection.

My 96 ranger check engine light came on, I brought it to the part store to get it scanned and the codes cme out "bank 1 and bank 2 too lean" but it doesnt seem to affect the performance of the engine. What are some possibilities that it could be.

I own a 1996 Ford Ranger 4.0 liter V6, manual transmission that I pull behind my motorhome. At about 75000 miles the Check Engine light came on (and stays on). Local Ford Dealer tried about $300.00 worth of sensors, but after a few days the "check engine" light would come back on. Finally, they told me it would take "extensive diagnostic and repair charges" to repair the defect and suggested I might "drive it like it is". I have driven it for about 60000 miles since that time and the light still is on.

However! I spent a week in Estes Park, Colorado (at an elevation of 6800 feet and above) and after the second day the light went out and stayed out all the time I was there. When I returned home the lamp came back on after only one day. I went to the Ford place and told them about that. They suggested it "might be" a "pressure" sensor or "altitude" sensor, but couldn't be sure. They wanted another $300 or so to find out. I said no.

Can you help?

Thanks,
Ron

Thank you for your reply.

I no longer remember the codes given me by the Ford dealership 60000 miles ago. I tried to get Auto-Zone to read the codes, when I got back from Colorado, but they say my truck has a computer plug that does not match anything they have. Also, I have purchased two different "Code Readers" from different sources and neither of them would match the plug on my truck. I was told that Mazda intentionally put this plug on because Ford wanted to have the only reader that would fit.

I know this isn't a help, but I'm kind of "in a pickle".

There is one other thing that I have noticed the truck doing but I don't know if it's related or not, and I don't remember if it started doing this after the check engine light came on or not. It ONLY does this in the hot summer time (July or August) and after the truck warms up by driving it 8 or 10 miles with the air-conditioning on. When the engine idles down below 1500 RPM I hear a very low pitched "whistling" sound -- more like a "moaning" sound. The slower the engine idles the louder the moan. I raised the hood and it was coming from the air input duct work into the top of the engine. It's almost like a "vibration" because you can lay your hand on the duct work and feel it. Tapping the accelerator pedal will stop it until the engine idles down again. Naturally, during the normal course of driving the engine is usually above 1500 RPM and I never hear it -- only at stop signs or such.

Can that be related?

Thanks,
Ron

I've got my father-in-laws Ford Ranger this week while they are on vacation, and the check engine light is (has been) on. My father-in-law says that he took it somewhere and they said it was an "emissions thing". Don't worry about it.

Well, I'm not that way with my vehicles, so I put my CarChip on and ran diags. The code that comes up is: P0401 Exhaust Gas Recirculation Flow Insufficient Detected

I took the EGR off and cleaned it up, reset the light/codes and took it for a drive (about 12 miles. A block from getting back the light came on again, same code.

I purchased a new EGR valve tonight, installed it, reset the light, and drove the same "test route". About 6 blocks from the house it came back on.

I also pulled one of the spark plugs tonight and it looks oiled/sooty. And overgapped. I figure the truck is running rich with the current problem which would account for the "oiled" look, and I noticed the plug wires are looking pretty worn/cooked. I have new plugs that will work in the truick and will get new wires tomorrow. - I doubt that will fix the problem though.

I'm open to ideas guys and gals.

The truck has the 3.0 liter V6, automatic trans, and 126,000 miles on it.

My in-laws come back Saturday am, and I would like to give the truck back in a little better shape than the left it. They really do a lot for us, so I don't mind spending some time and a few dollars on it.

Thanks.

John

- It was pretty late ;ast night when I finally got around to fixing this last night, so I didn't get it posted that I got the problem fixed.

It was the EGR Position Sensor/DPFE Sensor.

Thanks for the reply though.

I have a 96 ford ranger auto. 2wd 4 cyl. Been a great truck. Just started having this problem. My o/d light will come on and off, and my check engine light will come on. Did it a week ago, but went out. Now it just did it again. Any idea what the problem is? Truck seems to still run and drive fine.

Great site :)

My o/d light blinks on and off, and my check engine light will come on. Did this a week ago, but went off. Just did it again yesterday.