99 4.0 ohv auto with 315k miles

[Bruces expo]

Drove it home 60 miles with nothing major happened , it had a shutter while in drive or in park when i bought it for cheap , knowing it didnt run right , thinking i could fix it easily , well i decided to change plugs that helped the sutter and shake some , then changed the oil with mobil super - high mileage and a fram high mileage oil fiter , that helped with the shake and shutter a little more , then learned the bosch platinum plugs i bought werent the best to use , so i swapped them out with Autolite double platinum plugs , that made the shake and shutter even worse , i cleaned the iac valve and that started humming , so i took it out for a drive to see if it would maybe clear up if i drove it for a few mins , or maybe set a cel off , no luck , so i looked at it running in park in the dark and saw something red , took another look and it was my exhaust pipe :thumbdwn: my first catalytic converter was Cherry red aswell as the second and third , but not the forth , or my exhaust manifolds on either side , im wondering if my catalytic converter's are clogged up from so many miles and not being changed , any advice or suggestions are welcomed and appreciated , Thanks long time member Bruce

 

[Rusty]

It is most likely they are clogged and it is causing the problems.

If you can find another set just swap them in and see if it makes a difference.

I had an explorer that had higher mileage and it would have similar symptoms I never did see the cats glowing but after replaced it ran much better.

 

[Bruces expo]

thanks rusty for the reply , im thinking of going to the local you pull it yard and grab a full set up , maybe i should grab 2 and do some cutting to remove one or two of them as i dont have emissions here , i also need a few other small parts to make the explorer complete

 

[osteologation]

thanks rusty for the reply , im thinking of going to the local you pull it yard and grab a full set up , maybe i should grab 2 and do some cutting to remove one or two of them as i dont have emissions here , i also need a few other small parts to make the explorer complete

If you dont have emissions and don't care just pull em and gut em. It's easy and still looks factory as there's no cutting or welding involved. I have used a crowbar and a hammer to bust em up.

 

[Bruces expo]

I'm still unsure on what i should do , i'm going to tinker with it today some and see what happen's

 

[Bruces expo]

Well time to work on this thing again , it has sat since i last posted and i jumped it off the other day and it started but all the same issues , CEL came on after about 3 mins of running , im thinking its the cats , but i have someone interested in buying it , i don't want to sell it to someone and it break down on them , not sure what i should do , sell it and tell them good luck , or try and drive it somewhere to get the CEL checked out , since it has so many miles on it im unsure of what to do , any info or advice is welcomed !!

 

[drbenz]

If the cats are turning red they are getting raw fuel fed to them, even another set of cats won't fix the basic problem. Bad engine sensors or leaking injector could be the cause.

 

[Bruces expo]

If the cats are turning red they are getting raw fuel fed to them, even another set of cats won't fix the basic problem. Bad engine sensors or leaking injector could be the cause.

thanks for the reply , but the cats only turned red the one time, after i posted last night i started the truck and let it run for about 10 mins, the coolant temp guage doesnt work so i cant tell when im at operating temp , i have it for sale at the moment , and i have it listed as not running properly but running , if i can trade it im going to !

 

[Bruces expo]

Well a Update i sold it for about $500 more than i had into it so i came out ahead , looking to find another first gen with a bad trans and do a swap and then sell for a lil profit , Well see how it goes

 

[FPGT24]

not to change the topic or anything but...you will have MORE problems due to using Mobil High Mileage oil and a FRAM oil filter. Mobil oil sucks balls unless its Mobil 1 its some of the cheapest garbage available look it up. I made the mistake of using this oil before in my one Probe GT that never burned oil and it burned through a crankcase of oil after driving it a few hours. Switched back to Valvoline, it was fine and didnt smoke or burn oil anymore. Don't get me started on FRAM oil filters...

none the less, over 300k miles on a newer Explorer and its still running? Must have been extremely well maintained. Ive seen the pushrods V6's in second gens hit that mileage before (not too common but quite common in the first gens) but its quite rare to see a SOHC or 5.0L with that mileage...most SOHC's die around 240k and 5.0Ls before 200k.

 

[masospaghetti]

I thought the 5.0 was the most durable engine of the three? It certainly has a more robust transmission.

My impression is that 5.0's were slightly longer lived than the 4.0 OHV, and far superior to the SOHC.