98 xlt 5.0 exhaust leak and p0420

[white_shadow]

im wondering if the two are related. is the o2 tripping the CEL for the code because of the exhaust leak? i can hear the leak under the hood with the engine cold and running. with the code being for inefficient flow through the cat because the exhaust is leaking upstream. what typically lets go on the exhaust system? collector gasket or exhaust manifold gasket? truck has 167k on it now.

 

[boominXplorer]

I bet the egr tube is rusted out in spots. Its the tube coming off the passenger side exhaust manifold.

 

[white_shadow]

I bet the egr tube is rusted out in spots. Its the tube coming off the passenger side exhaust manifold.

thats the side where the leak is. im guessing this is normal? are we talking brain surgery to replace? i can image countless heat cycles over 14 years and 167k miles is going to make the removal of the old parts interesting.

edit: wow, damn...local parts house has that egr tube for 60$. must be a fancy tube

 

[jremington59]

This might help you. I don't think the tube is kicking the CEL. If the tube were rotted it should also show an insufficant egr flow code.

http://www.obd-codes.com/p0420

 

[white_shadow]

This might help you. I don't think the tube is kicking the CEL. If the tube were rotted it should also show an insufficant egr flow code.

http://www.obd-codes.com/p0420

which side is bank one? drivers or passengers?

 

[jremington59]

Passenger. You're exhaust leak is probably your manifold. The 5.0's are notorious for them cracking on that side. Mine included.

 

[white_shadow]

Passenger. You're exhaust leak is probably your manifold. The 5.0's are notorious for them cracking on that side. Mine included.

where would i get a new manifold? im not spending hundreds on headers.

 

[celly]

where would i get a new manifold? im not spending hundreds on headers.

They're all over eBay. No idea about quality. I'm in the "Torque Monster Clique".

 

[jremington59]

I got mine through Rock Auto for around a hundred dollars. But you need to make sure that's the problem first. Do you hear a ticking sound with the exhaust leak?

where would i get a new manifold? im not spending hundreds on headers.

 

[white_shadow]

I got mine through Rock Auto for around a hundred dollars. But you need to make sure that's the problem first. Do you hear a ticking sound with the exhaust leak?

i did not notice any ticking. this weekend im going to pull the wheel off on that side and start the motor cold and see what i find.

 

[white_shadow]

had the wheels off to do brakes and new wheel bearings...totally forgot to start the truck when it was up on jack stands and cold. i just ordered the UCA's and lower ball joints, hoping they come in before this weekend. when i have the suspension apart ill try to remember to check the EGR tube, im hoping thats all it is. this damn noise is driving me crazy. also, once the motor is up to temp, i dont hear the noise any more, its only when its cold.

 

[white_shadow]

ok a couple weeks ago i replaced the egr tube, that was an interesting job, the part from RA was not bent properly, so it had to be " modified ". i reset the CEL and it was off for a couple days. then it came back on. exhaust system has no leaks that i can find. engine runs like a champ. just got this damn CEL light on. if i wasnt OCD about it id just let it go. what next?

 

[jremington59]

If you're sure there isn't an exhaust leak then most likely your problem is a bad O2 sensor behind the cat converter or the cat converter itself isn't functioning properly.

 

[Chikar]

I'd suggest getting the DTC codes read. If the CEL is on it should have set a code in the PCM and that will point you in the right direction.

 

[jremington59]

He got it read. It was P0420.

 

[Chikar]

OOPS, missed that in the little of his original post.

 

[Ford3t]

97 xlt 5.0 exhaust leak

I've been reading these posts on the exhaust leaks and am looking for advise. My '97 explorer AWD seems to have an exhaust leak on passenger side manifold also. I just replaced a bunch of stuff including EGR tube and muffler (that was fun -- not). Still getting this Check engine light. The EGR excessive flow. I thought EGR was ok but maybe not. Just failed inspection because of "leaking/loose exhaust". Inspector didn't give specifics but said "just listen to it". I guess I don't have the right ear for that. Sounds ok to me. My friend (expert mechanic) thought I had the manifold leak. We thought it went away after the EGR tube fix or at least when engine is warm but maybe not. The engine is Full of rust and I've spent a ton of money already on other stuff. Any ideas on what to do without putting another $500+ into this? And even if I go for new manifold, not sure it's doable with all the rust.