6.0 with P0300 and loss of power

[mikekey]

I have observed most dealers and their techs being full of shit 92% of the time.

[Moots1288]

I have observed most dealers and their techs being full of shit 92% of the time.

I can agree on that. Just got my money back from one dealer, theyre a bunch of lying scum and they usually try there hardest not to warranty anything.

[DustinC1989]

Hence why I'm the only person that works on any of my vehicles.

What does the Illinois emissions test all include? Do the have a sniffer test? Or just check for codes and visual inspection?

[ErikSS]

The standard is just an OBD check. However, they can do a visual. I have actually had a sniff test on a basically stock Dodge Ram also. So, I think if they have reason to believe (maybe a lifted TBSS) that I have altered something they can do any of the tests they want.

[DustinC1989]

Well it seems like the dealer isn't going to warranty it
Sounds like the only options to play this weekend are pay to have it replaced tomorrow, or hollow them til you get a replacement

[navigator]

when I was a teenager, I hollowed the one out on my 85 Nissan pickup.
That was a pretty good job. I put a crow bar in a vise and kept slamming the cat honeycomb onto the crowbar until it was broke up pretty good and it all fell out.

[mikekey]

The standard is just an OBD check. However, they can do a visual. I have actually had a sniff test on a basically stock Dodge Ram also. So, I think if they have reason to believe (maybe a lifted TBSS) that I have altered something they can do any of the tests they want.

OBD check can be solved with a tune Erik. Go catless or get yourself a high flow cat, do you have two or one cats btw? If you have two, you really should spend the extra buck on SLP high flow cats or another reputable brand, if you are going to stick with the cats and not upgrade your exhaust.

If you are thinking of upgrading the exhaust at some point down the road, then the cheaper bet might be to just replace them with whatever is cheap. Unless you plan on doing a cat/back exhaust upgrade. If that's the case, get the high flows, if you're doing a headers back, I'd hollow some out.

[v7guy]

If you think it was the cat, go get some low resistance muffler bearing, cause I'd bet that when you pulled the pipe down you just bypassed the flow on the bearings that are going bad and it suddenly seemed fine, the dealership told the brother of a guy a I know that cats never go bad man.

[mikekey]

Probably should check the blinker fluid too.

[ErikSS]

I checked the blinker fluid. I even topped it off for good measure. You think those muffler bearings could be the root problem? They did have a little play but I figured it was ok!!!

[Moots1288]

[Trail X]

There's still not very good evidence that your cat is the true problem. I'd be inclined to get some better evidence.

You can replace the upstream O2 sensor with a pressure gauge and read that while revving the engine. Apparently with the engine held at 2k rpms, the pressure should be less than 1.25 psi gauge. A bad cat clog will read over 2.5 psig.

I'd think an exhaust place would have this sort of gauge.

There is some amount of truth to unplugging the O2 sensor, not sure if it applies to your situation, but the ECU will often go into an open loop mode if the O2 is unplugged. Open loop uses the MAF readings more than the closed loop modes do. You might want to check a scangauge to see which mode your engine is operating in. Normally if the engine is running poor and unplugging the O2 sensor helps the idle, then it can indicate a bad O2. Not 100% on this, but both O2 sensors might need to be unplugged to actually put the ECU in open loop.

[ErikSS]

I'd be inclined to get some better evidence.

I unscrewed the O2 sensor and drove the truck. Major difference. Thanks for the numbers, I didn't have those or I would have tried with my gauge kit.

I cut the Cat out, and put in a piece of flex pipe. I figure if this fixed the problem I could run down and have a cat welded in. I made NO OTHER CHANGES. I have full power now. I couldn't spin my tires on ice... now it rips them loose. It was the cat. No doubt about it.

I will debate having a stock cat welded in for $250 or just start piecing together a header and flowmaster dual exhaust system.

[Spot u 3]

Man bro I'm glad we got it figured out!! When the weather breaks we can swap SS's for a few days!!! Hold on to your nuts bro!anytime you need me just call me and thanks for helping me swap out the hub.

[TBYODA]

Start piecing together a header and flowmaster dual exhaust system.

You know you want more power!

[ErikSS]

Dave, thanks for your help man. I wish I had been able to tear into my truck a few days sooner but Stacey's car was broke down. Trading trucks for a few days sounds awesome!
Robert, everyone wants more power. My purpose would be sound function as well as performance. I'm not expecting noticeable gains from exhaust alone though.

[mikekey]

Dave, thanks for your help man. I wish I had been able to tear into my truck a few days sooner but Stacey's car was broke down. Trading trucks for a few days sounds awesome!
Robert, everyone wants more power. My purpose would be sound function as well as performance. I'm not expecting noticeable gains from exhaust alone though.

Actually you might, I saw 40rwhp on the dyno with headers and exhaust on the GXP.

But you know, you might not want to go to crazy with performance mods outside exhaust and a tune. More things that you could potentially have to worry about fixing; that one probably doesn't want to worry about fixing off-road. Nor do you really need 400rwhp off road unless you're doing a BAJA rally or some crap IMO. Low end torque is where it's at, you've got plenty of it.

NOw, a nice sounding exhaust however is always a plus. I wish my Trailblazer sounded more v8ish. I can listen to a v8 rumble all day. Although drone is annoying.