P0300 misfire help

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Tonyrodz

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So all valve's are messed up cyl 6 is toast and cyl 7 ring's are gone .. gonna rebuild the whole bottom end and top end...


So looking at getting some mods in while I have the motor out. This is a overland vehicle and nothing crazy family hauler etc... Should I keep the egr system or delete it? I found 2 pairs of headers also one with the egr but the driver side headers looks really funny.


What's a good small cam and what engine management do it need?
What do you think caused the issue?
 
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Tmoney10

Tmoney10

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E85 fuel!!!

I purchased the vehicle used 198k on it.

It's a flex fuel vehicle.

But engine was swapped over at some point and a non flex fuel engine was dropped in. I didn't know it so I messed it up with the flex fuel. :(..
 

Rocket Man

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I didn’t think the 04’s still had EGR. I deleted it on my 02, just removed the stuff and added a block off plate. This was required for the blower I put on it but the system is worthless anyway. If you go that way you’ll need to delete it in the tune. If you’re running a cam you’ll most likely need a tune anyway so you could just take care of both those. Blackbear Performance does my tunes through an Autocal I bought, data logs and tunes are sent via email and the service is good for as long as you keep the vehicle ie retunes for no additional cost.
 
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Tmoney10

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Ya no egr on 04 suburban...

I ordered a set of long tubes as my cats are completely burned up
 
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Tmoney10

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Just got the crappy ebay long tubes with y pipe.$250 shipped.. I've herd great success with these headers also and seen many reviews.
I'm not gonna do a cam after all as there really ain't a point for me to do it. Since this is a overland vehicle not a race car.

Both side of the cats on the oem set up are completely burned out...so the long tubes are a cheaper source for me
 
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Tmoney10

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Got the engine out and ordering the parts. Just gonna rebuild the motor with oem gm parts. And not gonna do a cam or anything...
Just throw in the long tube headersIMG_20210717_102542.jpg
 

OR VietVet

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Gonna rebuild yourself, right? Good call on the parts. Remember, "cleanliness is next to Godliness" when rebuilding engines and don't be afraid of cam lube. Reusing pistons?
 
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Tmoney10

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Naw gonna get new pistons also..
Something keeps telling me to get a cam since I got everything out lol..


Yes rebuilding my self with the help of my father in law.


I wanted to get a bnr stage 2 cam.

But not sure on how to get a tune to make it run okay
 

OR VietVet

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At least get a stock cam and new lifters and pushers and rockers. Fresh done heads at a trusted machine shop? Or gonna get all new heads?
 

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