Greetings, I have quite the story I will share before asking these questions. Bought an 01 F body with a freshly rebuilt motor. Has headers as well as mild cam and supporting mods. Guy I bought it from said to not take the engine over 5000 rpm and change the oil after 500 miles because it needs a final break in. I had been only driving the car around on back roads and going easy (just checked oil and coolant before this incident occurred) It ran perfectly for 460ish miles until one day I was cruising with my buddy going 70MPH in 4th gear and the car shut off. No smoke, no weird smells, nothing. I attempted to start it back up and it was only running on 4 or so cylinders. Oil pressure was fine, no weird bangs or pings. I was able to get it home as my house was only 2 miles away. As I was crawling it home, the check engine light was flashing so I figured it would store a code. I got it home and hooked up an OBD reader and to my surprise it did not store a code. When I try to start the car, It runs like when you don't pull the choke and try to start a cold engine. It just sputters, kind of fires in a few cylinders, then dies. I pulled the plugs and half of them were wet with fuel. Replaced them with new plugs and got no result. Took car to my dads buddy to get diagnosed, he wasted 2 weeks of my time and did nothing. After this, I took the car to Brady's High Performance in Lancaster Pa. After inspecting the car, Bradys alleged to me that I have a spun crankshaft bearing and I need my entire engine rebuilt! Previous owner said he polished crankshaft, put new bearings, and LS7 rods in. Bradys says there was shavings in the oil, but previous owner says that is normal for a freshly rebuilt engine and insists his friend has rebuilt many engines for his drag cars. At this point, I do not think that I have a spun bearing because my engine does not knock when trying to start, and maintained proper oil pressure the entire time. When I get it home from Bradys Im going to try to pinpoint the problem myself. I figured I could save $ by having them diagnose but all they want to do is take my $. I think the problem is spark related. Although it has all new sensors, Im going to replace the crank and cam position sensors, as well as get new coil packs. It has new plugs and wires, any other suggestions?

ANYWAY sorry for all the bs, does it sound like I have a spun bearing? If I don't have a spun bearing, what could be the cause of my issue?

 

You could have a spun bearing, maybe not. That's not something that can be diagnosed over the internet with the information provided.

Cut the oil filter open and inspect it.

 

I had a similar issue and ended up being crankshaft sensor not reading the reluctor wheel correctly. Fresh build also.

 

It sounds to me like some cylinders are not firing.. Wet plugs typically indicates no spark. So.. Could be the the coil pack on one side of the engine is no longer receiving power, or signals.. Test spark on all 8 cylinders using one of those test lights BEFORE you do anything else. Could also be crank position sensor, or cam position sensor. As stated above.. I'd cut the old oil filter open and check for signs of imminent death. Then test all 8 cylinders for spark. Between those two things, you will know what needs to happen next.

 

Your description DOES NOT sound like a spun bearing to me at all.

 

Start with coil packs fist, they are fairly cheap. If nothing then more then likely your crank sensor but wet plugs means 0 spark and that's directly tied to your coil packs. Make sure that you're at least getting a signal to the main coil pack plug.

 

LilJayV10, I have cut open the oil filter and below is a picture of what I found. You can see some metal shavings as well as the brass shavings witch only come from crank bearings. I still do not think I have a spun bearing, my engine doesn't knock and I have oil pressure. There are videos on youtube of LS1's with spun bearings and they idol normally while having very obvious rod knock. My car does not idol, and does not have any rod knock when I try to start it. Do the small brass shavings in the oil indicate that I have a spun bearing? Or is this normal for freshly rebuilt engines?




Thank you all for your help.