Well.. I decided to delve back into my '95 Blazer's intake again, as my symtoms are getting worse. Rough idle, now literally lopes and lurches with each cycle - almost like it's huting for an idle speed... but gives the same symptome that I was getting last year when I replaced the Spider Kit / Nut kit.

Yesterday, it started making a loud "thumpy" type of hissing noise from under the hood when I accelerate from a stop, and it feels like I've got very much decreased power from the engine.

Last week, I opened up the intake, and saw some fluid... But I didn't realize it (or it just didn't click) until this morning when I opened it up again - that the fluid DOES NOT smell like fuel.. It's oil. So I really don't think that my 6-7 month old spider-kit and nut kit are leaking fuel. But I DO know that there's an oily film all in the intake, and some small (i.e. 1 teaspoon) pooling of oil in the lower portions of the plenum. (see photo - hilighted areas with green dashed lines)

It was suggested last week to check the Cat. converter for clogging by removing the o2 sensors upstream and downstream of the cat. converter... Unfortunately, my '95 only has 1 o2 sensor, and it's upstream of the cat. converter.

So far, no check engine light, and no thrown codes... just 12, 12, 12...

What would cause the oily coverage shown below, and the slight pooling - along with the lack of power & rough idle? The noisy acceleration? Unfortunately, this is my only work truck - and geez... It seems like it ought to be something pretty simple... But I dunno.. I'm kind of at a loss mentally right now to figure out what to check next.

Thanks all, in advance, for your assistance again.

Rex S.

 

Checked all plugs. 2 looked fine (brown), 1 was black, and 3 were white (lean condition implied). So I figure maybe it may in be linked to my running conditions.... Getting noises from one plug area - gotta figure out which one, though... Hope it's not a stripped plug hole.

Okay - Went and got a fuel pressure gauge at Auto-Zone.... And all appears pretty close to spec...

Key turned to "On" position : Appx 58psi - then takes a bit but bleeds down to appx 46psi (I think there's a leak in the bleedoff valve of the tester, as there were bubbles forming and flowing during this time) (Hanes manual says 58-64psi on CMFI systems)

Ignition & engine turned on: 53psi - holds steady - (Haynes manual says pressure decrease of 3-10psi for running engine)

Thanks,
Rex

 

My gut instinct is telling me that my problems are a clogged catalytic converter. I had it changed about 4-5 years ago... and they welded both ends on, so I'll have another put inas finances allow later in the month.

Oh - Had to get a new sparkplug for Cyl #3 (middle drivers side) - that was a booger to get into place, even with a u-joint adapter for my socket set.. the original plug had stripped out several mm of the threads so it wouldn't go in... All is good with the plugs now.

As for the roughness when driving - I only get it at acceleration, now. I'm thinking that backpressure from the catalytic converter may be blowing back through the valves, and blowing the oily film into the intake plenum.. Does that sound feasable?

Rex

 

that sounds feasible, but what clogged up the cat in the first place?

 

Well, I had ran the Blazer with a leaking spider kit for about 1-1/2 years... Rough... Rich.... And constantly smelled of gasoline...

Just a speculation, but that's what I'm suspecting... If anyone has other ideas - please feel free to offer them forth..

Thanks,
Rex