1992 Ford F150 - Cat delete project

[dhermesc]

Just picked up a 1992 Ford F150 with a 300 6. The exhaust is falling to pieces, and it appears the cat is clogged, smog pump is long gone. On a 1992 the (working) oxygen sensor is BEFORE the catalytic converter - so no computer issues. I am looking at cutting the cat off (dual inlet) and replacing with a dual inlet muffler where the cat was and running a single pipe out the back or out the side. Anyone done this? Or is it easier to get a "Y" pipe and run single. To my knowledge in Kansas, it is illegal to remove a WORKING emissions system from a vehicle - this one is not and has not for years. Removing a nonworking emissions equipment is legal - but very difficult on newer vehicles with O2 sensors before and after the cat.

 

[psimmer]

Just picked up a 1992 Ford F150 with a 300 6. The exhaust is falling to pieces, and it appears the cat is clogged, smog pump is long gone. On a 1992 the (working) oxygen sensor is BEFORE the catalytic converter - so no computer issues. I am looking at cutting the cat off (dual inlet) and replacing with a dual inlet muffler where the cat was and running a single pipe out the back or out the side. Anyone done this? Or is it easier to get a "Y" pipe and run single. To my knowledge in Kansas, it is illegal to remove a WORKING emissions system from a vehicle - this one is not and has not for years. Removing a nonworking emissions equipment is legal - but very difficult on newer vehicles with O2 sensors before and after the cat.

Cat on my 96 F150 plugged a couple years ago. A friend put it on the hoist, used a grinder with a cutting wheel and cut it open. Gutted it and welded it back up. Its still in place, just hollow. Check engine light was on before he did it and is still on. Runs fine at 291K.

 

[Blackhole49]

My brother got a 2005 Ranger in Stockton CA in 2016 with 100k on it. It wouldn't pass CA inspection because the check engine light was on. Ended up both converters were plugged. In CA, emission work has to be done at a certified shop. Two shops told him not only did it need new converters, it also need the top end of the engine done (they claimed that was what caused the converters to plug). Estimates were in the $4,500 range. I flew to CA and we cut the converters off, punched the guts out and welded them back on. I took a 6,000 mile "road trip" home with no issues. Now have 160,000 on truck and only thing is, the check engine light is still on. You think it would have burnt out by now.

 

[wore out]

Just picked up a 1992 Ford F150 with a 300 6. The exhaust is falling to pieces, and it appears the cat is clogged, smog pump is long gone. On a 1992 the (working) oxygen sensor is BEFORE the catalytic converter - so no computer issues. I am looking at cutting the cat off (dual inlet) and replacing with a dual inlet muffler where the cat was and running a single pipe out the back or out the side. Anyone done this? Or is it easier to get a "Y" pipe and run single. To my knowledge in Kansas, it is illegal to remove a WORKING emissions system from a vehicle - this one is not and has not for years. Removing a nonworking emissions equipment is legal - but very difficult on newer vehicles with O2 sensors before and after the cat.

My B-I-L has a '92 with the 302 V8 and removing the cat changed air flow characteristics through the engine beyond what the computer can compensate for and it has driveability issues.

This is a known problem with the V8 Fords of that era, it MAY not take much of a "mod" to get your straight 6 into the same situation, I don't know.

You won't know for sure how yours will react 'til you try it.

For a vehicle that is not your main highway/extended trip unit, even if there are SOME issues it probably won't be so bad it's not driveable.

 

[dhermesc]

My B-I-L has a '92 with the 302 V8 and removing the cat changed air flow characteristics through the engine beyond what the computer can compensate for and it has driveability issues.

This is a known problem with the V8 Fords of that era, it MAY not take much of a "mod" to get your straight 6 into the same situation, I don't know.

You won't know for sure how yours will react 'til you try it.

For a vehicle that is not your main highway/extended trip unit, even if there are SOME issues it probably won't be so bad it's not driveable.

This will be my high school son's vehicle. Biggest issues is making sure the seatbelts are good as I have a feeling this one might not make the long haul.

 

[JMOR]

Is that due to the backpressure that the CAT caused?

 

[JMOR]

 

[RCP]

My B-I-L has a '92 with the 302 V8 and removing the cat changed air flow characteristics through the engine beyond what the computer can compensate for and it has driveability issues.

This is a known problem with the V8 Fords of that era, it MAY not take much of a "mod" to get your straight 6 into the same situation, I don't know.

You won't know for sure how yours will react 'til you try it.

For a vehicle that is not your main highway/extended trip unit, even if there are SOME issues it probably won't be so bad it's not driveable.

Has he tried sticking something into the exhaust pipe to create back pressure and see if the problem goes away?

 

[Phill Tibbetts]

My brother got a 2005 Ranger in Stockton CA in 2016 with 100k on it. It wouldn't pass CA inspection because the check engine light was on. Ended up both converters were plugged. In CA, emission work has to be done at a certified shop. Two shops told him not only did it need new converters, it also need the top end of the engine done (they claimed that was what caused the converters to plug). Estimates were in the $4,500 range. I flew to CA and we cut the converters off, punched the guts out and welded them back on. I took a 6,000 mile "road trip" home with no issues. Now have 160,000 on truck and only thing is, the check engine light is still on. You think it would have burnt out by now.


View attachment 110315

Some peoplle have been known to rermove troublesome check engine lights.

 

[Blackhole49]

Some peoplle have been known to rermove troublesome check engine lights.

My son keeps telling me to remove the bulb. I've gotten so used to it, I'd think there was something wrong with the truck if it wasn't on.

 

[Rich'sToys]

Do you do all your own work? I'd be surprised if a shop would touch it after that had been removed.

 

[teddy52food]

Many years ago I did a valve job on a chevvy 6 pickup. When I warmed it up & adjusted the lifters a friend came here. I shut it off & said after I put all that stuff back on it will be done. He said well you just had it running so why do you need all that stuff back on?????????????????????????????

 

[dhermesc]

Do you do all your own work? I'd be surprised if a shop would touch it after that had been removed.

Never been an issue yet. Son has a 1992 F250 with the 5.8 - cut them off at the down pipe and ran dual exhaust out the back. The pre OBDII computer Ford pickups are pretty resilient to throwing codes.