- Joined
- Jan 29, 2022
- Messages
- 101
I have a 2001 Chevy Blazer with the 4.3 Vortec. It only has 107k miles. I bought it with 103,300 ish miles.
So about 2 months ago, random misfires started occurring. I've been having random misfire issues on cylinder 1,2,3, and 4 for about two months. These cylinders are the two front cylinders, and the middle cylinders on each bank.
The engine was running rough enough for me to realize that my engine was misfiring. About once a week, I would get a P0300. The P0300 was always pending, but once a week, the counts would rack up and cause the engine light to come on.
About 6 months ago, I’ve replaced the spider injectors, and the lower intake gaskets, so I knew these weren’t causing the misfires. I also always run a bottle of Techron about once a month, so I knew the fuel injectors were clean enough.
So I checked the distributor, spark plugs, wires, ignition coils, ICM, and the vaccum. Camshaft retard was also at 0 degrees. Everything was in great shape and was working properly, verified by my scan tool and the tests I performed. When I took the distributor out, the lifter valley was pretty brown looking, little bits of sludge on the inside. But the distributor gear didn’t have that much wear on them. Rotor and cap was also clean. I also took off the valve covers to actually look at the rockers to make sure they were opening and closing all the way, and they were.
So I decided to do a compression test. And the compression on cylinder 1,2,3 and 4 was lower than the rest. Number 1 was the lowest of them all, reading at 105psi. I got worried, because I was thinking maybe somebody swapped a junkyard Vortec before I bought it.
I had a bottle of marvel mystery oil laying around in the garage, so I added some to the crank case. I drove with it in my engine for about 3 days, and the misfires disappeared. The engine started smoothing out the more I drove it. The misfire counters are reading zero now, and the history counts are also zero.
I just checked the compression again yesterday, and the compression was all pretty much equal across all cylinders, nice and high in the 145-155psi range. I took the distributor out again, and the lifter valley was noticeably cleaner, still brown, but the bits of sludge was all gone.
The crazy thing is I’ve been using Mobil 1 0w40 Euro oil this whole year, and I’ve been changing the oil every 3 months. What’s up with that BITOG?
So, the moral of the story is, MMO does work.
I don’t know how well it works as a fuel system cleaner, but it sure did work very well in the crank case for me.
Anybody that has low compression, and a dirty engine, use some MMO. It works very very well. I don’t think it’s snake oil
So about 2 months ago, random misfires started occurring. I've been having random misfire issues on cylinder 1,2,3, and 4 for about two months. These cylinders are the two front cylinders, and the middle cylinders on each bank.
The engine was running rough enough for me to realize that my engine was misfiring. About once a week, I would get a P0300. The P0300 was always pending, but once a week, the counts would rack up and cause the engine light to come on.
About 6 months ago, I’ve replaced the spider injectors, and the lower intake gaskets, so I knew these weren’t causing the misfires. I also always run a bottle of Techron about once a month, so I knew the fuel injectors were clean enough.
So I checked the distributor, spark plugs, wires, ignition coils, ICM, and the vaccum. Camshaft retard was also at 0 degrees. Everything was in great shape and was working properly, verified by my scan tool and the tests I performed. When I took the distributor out, the lifter valley was pretty brown looking, little bits of sludge on the inside. But the distributor gear didn’t have that much wear on them. Rotor and cap was also clean. I also took off the valve covers to actually look at the rockers to make sure they were opening and closing all the way, and they were.
So I decided to do a compression test. And the compression on cylinder 1,2,3 and 4 was lower than the rest. Number 1 was the lowest of them all, reading at 105psi. I got worried, because I was thinking maybe somebody swapped a junkyard Vortec before I bought it.
I had a bottle of marvel mystery oil laying around in the garage, so I added some to the crank case. I drove with it in my engine for about 3 days, and the misfires disappeared. The engine started smoothing out the more I drove it. The misfire counters are reading zero now, and the history counts are also zero.
I just checked the compression again yesterday, and the compression was all pretty much equal across all cylinders, nice and high in the 145-155psi range. I took the distributor out again, and the lifter valley was noticeably cleaner, still brown, but the bits of sludge was all gone.
The crazy thing is I’ve been using Mobil 1 0w40 Euro oil this whole year, and I’ve been changing the oil every 3 months. What’s up with that BITOG?
So, the moral of the story is, MMO does work.
I don’t know how well it works as a fuel system cleaner, but it sure did work very well in the crank case for me.
Anybody that has low compression, and a dirty engine, use some MMO. It works very very well. I don’t think it’s snake oil
