The change in RPM is the Torque Converter locking and Unlocking. So that's just normal. As far as leaving in the crankcase, it breaks down the oil as well as picks up sludge and stuff that's stuck on the engine. It can damage the engine due to friction build up at the crank and cam. When you put it through the brake booster line, it goes directly into the intake and gets burned through the engine.

 

[quote=jcpc83;415710]The change in RPM is the Torque Converter locking and Unlocking. So that's just normal......no its not that...if i had compair it to something it would be like its running out of gas. like a chugging feeling. and i know its not right buy i just did a tune up on it..plugs wires cap and rotor. so i guess we will see what that does.

 

that's the same as pouring a large cup of diesel down your carb, and letting it sit over night.

will smoke like a mother's mother, but will clean every last bit of carbon outta your cylinders.

 

Hey guys not so mechanically smart newb here. When you guys are talking about puttin the sea foam in the brake line,is there anyway someone could post a pic and mspaint maybe ? Yea I know sounds goofy I just dont wanna mess nothin up. I already have to dump 1500 into my 1500 98 blazer.

 

no pic's needed brother.

just pull the rubber line that runs from your power booster off. remove the check valve that comes out of the actual booster, and slowly pour in some of the Sea Foam (either a full can or half if your spliting it between your tank & engine).

don't let the engine stall, even raise the RPM's slightly to compensate for the Sea Foam mixture. let it sit as per directions, then go for a drive after.


have a little faith in yourself. it's really simple to do.

 

Get a timing light, and put it on your engine, and watch the timing mark at idle. Rev the engine a lil and see if the mark jumps around a lot. It will jump some. I had a cracked distributor housing that was allowing the cap to move a bit and was causing my RPMs to bounce around while holding the throttle steady. My problem was the plastic distributor. I'd like to try the sea foam another way, by putting it in through the intake tube where the IAT sensor sits. Unplug the map at idle, yes the engine can run I've seen it do it, and take a piece of vacuum line and put it in the can and insert it into the sensor hole while idling. I'll give it a shot later and let ya'll know if it works.

 

Or you could just get a can of SeaFoam Spray.

 

I read on the seafoam website that newer induction systems like the vortec don't have any vaccuum lines that distribute it evenly to all cylinders. What do they mean by "newer"? Does it even matter?

 

I keep getting engine code. #4 misfire

I was told the seafoam would cure this.

Any confirmations here?

Thanks,

 

I'm guessing you have the same issue I am currently having, it's a plugged injector. The seafoam may or may not help. The shop that I was getting my oil changed at this weekend said they would diagnose my CEL for up to an hour for $45. So I agreed and about an hour later they said that the injector is plugged and the whole assembly needs to be replaced and it is not a cheap fix. After digging around on this forum, this seems to be a very common problem for blazers.

Just before I left the shop, one of the mechanics came out and told me to try running a can of seafoam through a full tank of gas to see if it would unplug it before I dump a boat load of money into getting it fixed. I'm guessing that whoever told you that is thinking the same thing.