Getting 8.5 mpg need help

[swathdiver]

You're right, my mistake in that the lines from both the upstream and downstream look similar only while cold, not hot. Your bank 1 is more normal than bank 2 lower sensor, they should both respond to rpm changes.

Is the 93419 the whole enchilada, cats and y-pipe? I installed basically the same thing on mine in February, 51578 for GMT900, and it's working great and my mileage came back after a couple hundred miles as the cats wore in.

 

[BlueCollarTahoe]

You're right, my mistake in that the lines from both the upstream and downstream look similar only while cold, not hot. Your bank 1 is more normal than bank 2 lower sensor, they should both respond to rpm changes.

Is the 93419 the whole enchilada, cats and y-pipe? I installed basically the same thing on mine in February, 51578 for GMT900, and it's working great and my mileage came back after a couple hundred miles as the cats wore in.

not sure i just looked at the best rated ones real quick. looking at that video rhe S2 jumping is actually the one thts off? but off in a wat showing cat damage or o2 sensor damage?

 

[Scottydoggs]

MagnaFlow 93419 Direct Fit Catalytic Converter

thoughts on this replacement kit if it is indeed the cats?

hes in NY. if the cats are bad hes needs a CARB compliant cat to pass inspection, just like that ****** state CA.

 

[swathdiver]

not sure i just looked at the best rated ones real quick. looking at that video rhe S2 jumping is actually the one thts off? but off in a wat showing cat damage or o2 sensor damage?

The cat. If you want to double check the O2 sensor performance, swap sides and run another scan.

My right side cat had been changed out. Couldn't have been in there long as there was little salt corrosion. It failed before the original on the left and that resonator at the end of the Y had honeycomb material that the scrap yard paid me for too. Not sure if yours will have that. The point is, unless you're really tight on funds, change them both or all three. The Magnaflow Y is nicely designed and that alone should help flow.

 

[BlueCollarTahoe]

Going to laser tell check the cats
Will update then go from there i guess. I just hate throwing parts at something when ots expensive i rather know which direction for sure to head to.

 

[BlueCollarTahoe]

Update:

Got an unfrared thermometer laser. Whats the optimal condition to get the best reading? After putting it Under 2k rpm? After highway Driving? Idle at operating temp?

 

[BlueCollarTahoe]

Here are some readings sitting idle in park after highway driving for 15 minutes and the car is at operating temperature. This is about an inch above the cat and an inch after the cat wit the laser temp:


Driver side:

Before: 329
After: 345


Passenger side:
Before: 340
After: 358

Dobt know how accurste the reader is I tried to tske it in the same spots same distance away. What next? This is all F degrees.

 

[Scottydoggs]

id get it on the hwy and rip into it for a bit, then pull over and check em.

one cats much closer to the exhaust manifold right? could be why its a bit warmer.

 

[swathdiver]

That's the offending cat. Did you get the one from harbor freight? Bought on recently too, haven't used it on the truck yet.

 

[BlueCollarTahoe]

I believe th3 driver side one is the closer one. The pipe cuts across to the right side of the trick where the other one is. A lot of metal around it that's warm maybe why its hotter. Yea i got the one from harbor freight new batteries in it. What ya think i should do next?