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Hello,
I have a 2003 LM7 out of a truck that I rebuilt and put a very mild summit racing cam, springs, lifters, and pushrods in. Stock pistons and rods. About 3 months ago I swapped it into my car and I've been working on it here and there trying to get it running right. Recently, I seemed to have gotten it running pretty good, it's had 2 stuck injectors in the last 3 months which I've caught pretty quick and fixed. Those were on cylinders 6 and 3. Yesterday, I took the car on a longer trip (around an hour each way) and on the way there after around 45 minutes in it started running poorly. Cutting out with throttle and just missing a lot. Checked the codes and I was getting a p0102 and a p1133. Let the car sit for 2 hours or so and started on my way home with no issues. Took it to work this morning and it didn't want to idle cold, which isn't too abnormal but after 5 miles or so it started running so badly I had to pull over. I smelled a pretty bad burning smell so I opened the hood and found that the map sensor housing in the rear of the manifold had completely come off the manifold. I stuck it back in the hole and wedged some rags in to limp it to my work, and I removed the manifold to find that ports 8 and 5 were completely melted. The map sensor housing had also completely melted off of the manifold. Pictures will be attached. I'm at a loss as to what happened. I'll check to make sure no more injectors are leaking but I've never seen anything like this before.
Pulled the valve covers off and cranked it today, cylinder 7 exhaust pushrod didn't move at all. Time to pull the head and see how bad the damage is. Will return with updates.
I went ahead and pulled the head off the driver side and lo and behold the pushrod turned into a zigzag and the lifter was collapsed. Thankfully the cam looked to be okay. The lifter seemed to have plenty of oil on and in it so I guess it's time to contact Michigan motorsports and see if they'll even consider reimbursement for the damages.
I went ahead and pulled the head off the driver side and lo and behold the pushrod turned into a zigzag and the lifter was collapsed. Thankfully the cam looked to be okay. The lifter seemed to have plenty of oil on and in it so I guess it's time to contact Michigan motorsports and see if they'll even consider reimbursement for the damages.
As with any company selling high performance parts, they might reimburse you for the lifter but they're not going to cover a single other part that failed. That is industry wide practice, and hopefully you don't blame them for the issue, after all they didn't manufacture the lifters.
03-15-2023, 04:16 PM
LM7 Melted LS1 intake 
