mcnaught82

I talk to a mechanic lastnight and he said it is most likely the cats, and the knocking I hear from the motor is Spark Knock (Detonation). I hope I didn't fuck anything else up in the motor because of the detonation. I read that detonation can damage piston rings, rod bearings, head gaskets, and spark plugs. How can I tell if the piston rings are damage or the rod bearings?

Its a 2003 GMC Yukon XL 5.3L 123,000

Check PCV valve

Im tuned in.

True, Ill probably have the shop do it.

Ill do that, thanks

Yes, that was parts and labor. I though about doing that or going with this http://store.summitracing.com/partdetail.a...mp;autoview=sku I know its not smog legal but the cats are in the stoc location as the ones on my yukon.

I thought about doing that, disconnecting the exhaust from the headers and see what happens? How much does a back pressure gauge cost?

The shop next to my house told me they will replace each cat for $240 each.

Thats what I have been told also. I am going to replace both of them.

When I cleaned my K&N 2 months ago I cleaned the T/B also.

I haven't changed the O2 sensors yet but I am going to, I am going to clean the MAF because a couple month ago my Yukon through a code, I cant remember which one basically saying that the MAF wasn't reading correctly, that there was more air entering the motor and the MAF wasn't detecting the extra air. No there isn't a leak between the MAF and T/B. It doesn't leak oil at all. Chris D, the engine can still run and have a few bad spark plugs as long all of them aren't bad. I haven't tried REV my motor to the max while in park, since I don't want to risk damaging the motor more in case there is a small head problem. I do rev the motor to about 2000 RPM and when I let go of the gas it will drop down and almost stall out but than jump back up to normal and start idling like shit again. Right before it fucked up really bad I did floor it from a stop because I noticed my yukon felt a little weak in power and it didn't want to go fast at all. Basically it felt like a 6 cylinder instead of a V8 in my yukon.

Its a 2003, so it doesnt have a distributor, it has 8 individual coils for each spark plug.

Last week I started up my yukon and I heard a light tapping coming from the heads. So I checked the oil and it was barely even reading on the dip stick, and I still had 1500 miles till my next oil change, No my yukon was not smoking or anything indicating that there was oil burning. So I went down to the shop to get my oil changed and my engine light poped on so they scanned it for me and it came back with a P0420. which means ether the cat is plugged or my O2 sensor might be faulty. So this weekend I went to San Jose which is almost 200 miles round trip and I noticed my yukon was lacking power. On the way home it barely wanted to go over the mountain I had it floored and it was barely doing 30 MPH, so when I finally got to the next truck stop at the top I pulled over and noticed my yukon was idling really rough kinda like it was mis firing. I checked my oil and it was still full. I started down the hill and while I was accelerating my engine light started flashing, and I could only do about 30 MPH all the way home. When I would come to a stop and try to accelerate my yukon wanted to barely move and I heard alot of knocking in the motor. I though maybe my heads were damaged. I get home and I put it in park and I rev the motor and the knocking is gone, but as soon as I put it in drive and accelerate the knocking comes back. Could the problem be my cats are plugged and the back pressure from that being pushed back into the motor caused me to damage my spark plugs? Also when I start up my yukon right away I smell gas really bad, like the exhaust is blowing back into my engine bay. I checked my oil when I got home and it is still full. I know my head gaskets arent blown because the radiator fluid is still perfect and not oily and my oil doesnt look milky ether.

Mostly music, but also back up data.

The stepper motor are bad on the 2 gauges. Common problem with all GM Trucks. They have a newer version of the motor out that you can replace but you have to solder it in.

My buddy has 2 JL 12w7's for sale. He is asking $600 for the pair. Local pick up or drop off only.

By the looks of the Quad alts in your Tahoe Steve, you connected your grounds to the bracket on your alts correct?

Also you said run 4 grounds also front to back. When you run the 4 grounds from the back battery's, where do you ground them up front??

Steve are you saying to wire the 4 alts like this? But then when he gets the 4 D3100 wire each alt to each battery in the back than connect all 4 battery's together.

Let me get this right. If I run a battery in the rear, I need to fuse it in the front and put another fuse right before the wire goes to the second battery?

Ask steve what hard drive he used. He tore a computer apart and put it in the Escalade.

The deck has a built in DVD player

He needs it to play the music. Thats just a monitor in the dash and its connected to the fosgate 3 sixty to control the EQ. Correct me if Im wrong steve.

Damn that dash and center console is sexy.