I'm trying to cancel my order of the cats and get these. They are less than half of the price of the Magnaflow "drop-in" system. No welding is a huge bonus.

 

Oh well... They have already shipped them. NBD. It looks like at least the downpipe attachment is no-weld. I can have the other end expanded, I'm pretty sure, to make it no-weld also

 

This is still an age/mileage issue though.

To me it seems like a vicious cycle, something starts to go, which causes the car to run rich, which chokes the cats, which causes it to run even more rich, which chokes the cats even more, etc, etc...

The MAF and O2 sensors are really critical on these 2003-2005 cars. They are the main sensors that run the whole engine really.

In my mind they should be replaced preventatively at the 100k mark, same as the sparkplugs.

 

MAGNAFLOW MAKES A DROP-IN REPLACEMENT!!!

Driver's Side (North America): PN: 51224

Passenger's Side: PN: 51225

I have the old ones off now (both were verified by a shop as being DEAD, catalyst broken up and melted). I'm documenting the install with pictures and tips. If no one has documented the use of these cats, I'll be happy to do a detailed write-up

Should have her back on the road this evening!

Ken

 

So, got it all buttoned-up, cleared the codes and went for a long drive cycle.

Immediately, I knew something was wrong. Stumbling, kind of missing. I fired up Torque, and watched the O2 sensor traces. Both sides' voltage was up at .9V constantly. I could see the computer swinging short-term trims wildly, trying to get the mixture to lean a little to get the voltage down. No dice.

Suspecting the upstream sensors, I double-checked to make sure I hooked them up correctly (I was afraid I had swapped up- and downstream sensors). They were hooked up correctly, so I started pulling the upstreams to swap in the old ones to see if I could isolate. Driver's side came out and swapped in about 2 minutes. Passenger side was stuck. My lambda socket wouldn't budge it. I looked and found a 22mm spanner. No dice. Would not budge. Long story short: I pretty much destroyed that O2 sensor getting it out. What I found was awful: there was a dot of weld material in the threads of the O2 sensor boss. It destroyed the first 3 threads on the sensor. I have a picture, but you can tell I didn't cross thread it, because the threads above the weld spatter were perfect.

Tomorrow, I'll rummage through my machine tools and find my BIG tap and die set. I think I have a tap that is the right size. Rather than return it and fight with Magnaflow, I'll forgive them the manufacturing defect. I'm saving so much money compared to the $4.5k quoted by my mechanic, that I'll happily unmount that cat and clean up those threads with a tap.

Moral of the story: check the threads on everything before you start screwing things back together. Ironically, I DID clean up the threads on the exhaust manifold-to-cat studs, and the related nuts. Never thought to chase the threads of the cat itself. Brand new, why?

More tomorrow...

 

Chased the threads on passenger-side cat, upstream bung. Screwed in the old upstream sensor and fired her up. Still doing the stumble/miss thing. The MAF sensor that was in it is "new". However, I think it's out of spec for the car. The reason I think this is that when I was chasing down lean codes, I found this rebuilt Denso. Rebuilt. Sigh. It was cheap. It also instantly caused the car to start throwing rich codes. I swapped back to the other (old) MAF and that went away.

Ok, fast-forward to today. I had put that new MAF back on when I was troubleshooting the "no start" issue. It was still on it the car - and might be the cause of the cat meltdown - I don't know. So, I put the old MAF back on, and the stumbles and misses at idle stopped. However, after running through a long drive cycle, I had codes. I stayed out of the throttle, like a good boy.

So, here is the lay of the land:

New cats
New downstream sensors/old upstream sensors
Old MAF
New Fuel Rail Pressure Sensor
6 of 8 ignition coils are new.
All new plugs.

After saving the fault log, I tried a couple of WOT runs. Ugh. Chugging sound like there's maybe an exhaust leak (I torqued the studs to spec), RP message, and rev limiter @3k kicked in.

So, here's the codes:

P0300
P0301
P0305
P1000
P1316
P2097
P2099

 

The P1316 is the most worrisome. Yet another component failure to chase down, this time injectors?

 

You've got a couple of issues;

P0300 = Random Misfire Detected
P0301 = Cylinder 1 Misfire Detected
P0305 = Cylinder 5 Misfire Detected

P1000 = Nothing to worry about

P1316 = Misfire excess emission NOTE: This DTC will flag only when accompanied by an individual cylinder misfire DTC: P0300 – P0308

P2097 = Post Catalyst Fuel Trim System Too Rich (Bank 1)
P2099 = Post Catalyst Fuel Trim System Too Rich (Bank 2)

P-codes on Jags >P1000 are not always correct on website lists or even the Ford master list, so your P1316 has nothing to do with Injector Drivers if that's what you were worried about.

I'd say you probably have a couple of bad coils, and your downstream O2 sensors are the wrong type or damaged somehow. And a new genuine MAF would rule out other issues...

 

I have the downstream sensors that I took out of the original cats. I think I'll swap them back in. Also, I have all four of the coils that I replaced from that side of the engine. I can easily swap a couple back in. I got a batch of aftermarket coils, which I knew was a gamble

MAF will have to wait, but it's very high on the list.

Thanks

 

All right - swapped in the old downstream sensors, and changed out #1 and #5 coils (put back in the older ones that weren't bad anyway)... MUCH BETTER!

Did a long drive cycle, and everything was great. Did a WOT 30-60 run - it's been a while since she felt like that Did a 0-60 pull... Uh oh. Misfires. I pulled a P0300. I have more ignition coils, so I'll swap them out one-by-one, I guess

But, at anything less than WOT from a stand-still, the car is a rocketship again Me likey.

Ken

 

The car did me the courtesy of throwing P0302 and P0306 this morning, so I'll swap out those coils and re-evaluate

I was wondering if a failing EGR valve could cause an issue if it didn't close properly at WOT.