Check Engine Light - 1996 Explorer

[ratterrier]

Hi guys,

After many mostly trouble-free years, my '96 2WD Explorer has just thrown the Check Engine Light. I tried the old gas cap remove and replace, but it seems it's a real problem. I have a couple of questions I was hoping to get advice on, if you would be so kind...

I don't have a code reader, but saw in a post that maybe AutoZone might read them for me. I'm going to find that out tomorrow. If the problem turns out to be 02 sensors, from what I've seen there seems to be 4...is this correct? And if an 02 sensor is the cause, will I be able to determine which one? The price on these are about $48 each, and $200 bucks for me at this time is a bit tough...and that's if I can do the replacement myself lying on my back in my driveway.

Unfortunately I just had to drop over a $1200 for a timing belt/water pump, flex-pipe replacement and state inspection on my other car, so I'm hoping to be able to save some costs by doing things myself.

Thanks for any help!!

Richard

 

[rizzjc]

The code should point to the specific bank, but that's assuming it's that at all. Best to just get the codes read, than worry about what it COULD be, since it could be a LOT of things.

 

[ratterrier]

Thanks for the reply and sound advice, Joe !!

I stopped by AutoZone and they read the code for me (nice service). According to the scan, the truck registers a 0420 which ,according to the printout and explanation AutoZone supplied, is "The catalyst system efficiency for bank 1 is below threshold". So the counterperson's recommendation was that the spark plugs were probably bad. I wouldn't be surprised, as the truck is due for plug replacement.

I previously picked up new plugs and wires, but had delayed putting them in because they are Bosch and I'd seen some complaints here about them. Plus my understanding is that a couple of the plugs are a b*tch to get out due to access. But now, I'll do the work and we'll see how it goes.

Thanks again,

Richard

 

[rizzjc]

This might help:
http://www.explorerforum.com/forums/showthread.php?t=233407&highlight=P0420

 

[Joe Dirt]

Richard, if you remove the wheel splash shield, the plugs are not that bad to fix. If it was me, I wouldn't put in the Bosch plugs- some like, some hate, general consensus is more negative than good. There is no gain to be had for the possible need to swap 'em out later, just creates work. Just my .02!

 

[ratterrier]

Thanks again for the extra info Joe, and you also Joe Dirt for the plug suggestion. The Bosch plugs (and wires) have been a big reason for me delaying the plug changing. But the Bosch parts can't be returned, and I'd hate to just toss 'em...so I might end up using them .

I'm hoping that the plugs will do the trick, but after viewing the link for the other posts I'm not so sure. Well, one step at a time I guess. I'll let you know how it goes. First though, it seems it's also time to replace my hood struts unless I want to risk having the hood drop on me during the plug job.

Thanks for looking out for me guys !!

Much appreciated
Richard

 

[rizzjc]

I used the Bosch Platinum +4 in my 5.0, and they were fine for a while. One or two fowled after about 30k miles or so. I replaced with Motorcraft. Coulda been the plugs, or coulda been the oil I'm burning.

 

[Cobraguy]

explanation AutoZone supplied, is "The catalyst system efficiency for bank 1 is below threshold". So the counterperson's recommendation was that the spark plugs were probably bad.

I would LOVE to have that one explained to me....

 

[Turdle]

I would LOVE to have that one explained to me....

Same here
here is a redneck troubleshooting tip for ya-

swap the rear 02 sensors with each other,make sure to swap the connections also, disconnect the battery to clear the PCM fault codes , and see if the problem code moves to the other bank

if so it is the rear 02 sensor which is bad-

if the code remains the same-it is probably the catalytic converter-

 

[Mexplorer]

Check your catalytic converter and exhaust system:

It´s still good (no cracks,leaks)?
Does it smell like rotten egg ?
It is clogged ? have a helper with this: accelerate the truck in idle and see if the cat is glowing red (like a turbo engine). This normally indicates a very clooged cat.

Originally this code is originated because the front and rear 02 sensor voltage are fluctuating at the same range interval (and, the ECU senses the converter is not doing properly its job) and that is causing the P0420.

Try first the sugestions of the members . Catalytic converters at least here in mexico are not cheap, so i dont think they are cheap in the U.S, too.

I recently repaired my Explorer 96. It was giving to me the same code, but i am not require to pass inspection or something,so i did some of the cheap and easy fixes that are around the net. It cost to me like 3 bucks...

 

[ratterrier]

Hi guys !!

I'll be trying these tips in order of difficulty. I know for sure that the plugs are old, so replacement is needed anyway. I'll check to see if codes appear after that, and then try the cat sensor switch.

Regarding the AutoZone counterman's explanation...I have NO idea if he has any training or experience with the results from the code, but the printout I was given includes these probable causes...

1 - Cat converter defective (Failure possibly due to #2, 3 or 4)
2 - Engine misfires or running condition
3 - Large vacuum leak
4 - Engine oil leakage into exhaust-valve guide seals, piston rings.

So my guess is he was basing his judgment on the #2 misfire. Whether the cat is defective because of that, or if it is something that can return to normal after the misfire / running condition is corrected we will find out.

Much appreciated !!

Richard

 

[ratterrier]

Hi guys...

I'm finally getting around to do the plug swap. I had to replace the hood struts first, since the old ones gave the hood almost zero support. BTW, here's the best online price I found...Gabriel StrongArms (Made in USA !!) at $25.00 for the pair at partshighway.com.

Anyway, regarding the removal of the splash shield...pardon my ignorance, but is that the rubber piece held in by plastic pins, or does this mean the inner fender shield held on by screws that the rubber is attached to? Please advise !!

I also plan to give the plugs a WD-40 soaking or two before removal, because they have been in there for an awfully long time. I've seen where some folks have broken plugs and/or stripped threads, and that's something I don't want to have to deal with.

Thanks,
Richard

 

[ratterrier]

Ooops...sorry, memory failed me.

The struts were only $21.99 for the pair (better still) excluding shipping