97 Blazer A Strange Occurence
 

Went to seafoam my Blazer today before work and something strange happened.. it wouldn't pull it through. I noticed while spraying that the contents of the can were going the opposite direction and leaking out of the breather at the filter end! Never seen that before. I tried placing the hose in many different spots and positions, but it still trails back instead of getting sucked into the engine. Has me stumped.

So, I took the intake breather hose off like I do my 95 and was going to spray it without the hose attachment directly into the throttle body. The engine cuts off when I bring up the rpm's before I can ever start to spray. I try to keep it running but it acts like it blows back up out the intake when it bogs down. Almost like timing. I know this engine has a good amount of carbon built up from when I bought, previous owner was negligent. It has always been a little sluggish and bogs down when slightly letting on the throttle, but never stalls.

Work Done:
Nylon fuel line was leaking at the tank so I replaced all the ones off the sending unit with fuel injection hose and double clamped. No leaks. Replaced plugs, wires, dizzy cap and rotor. New crank sensor. Temp and fuel gauge half work. They don't read correctly. Testing to see if coolant temp sensor is bad later.

I am going to do a fuel pressure test, compression, spark, and timing when I get home tonight. Was wondering if anyone has ever run into this to maybe give me an idea before hand of why it may bog under a light load.

Edit: Once I get it up to about 10mph, it runs perfectly fine. No pinging, no sputtering.

Just got a 97 myself and am learning, anything come of this?