93 s10 4.3 start up and idle problem
 

Hello, I have a 93 s10 blazer 4.3(w) with 48000 original miles. The problems I'm having are an irradic idle, smoke and liquid coming out of the exhaust on start up, and coolant loss. The truck runs fine while driving, the problems only occur at idle and initial start up. It also takes several seconds of cranking before it will start. I have replaced every major sensor, the plug wires and plugs, the dist. cap and rotor, the ignition coil, and the entire exhaust system. The truck has been to 3 different shops and none of them have been able to get it fixed. Im thinking it could possibly be a leaking head gasket, but would that cause all of the problems I stated?. Any help would be greatly appreciated. Thanks

Ed

RE: 93 s10 4.3 start up and idle problem
 

Sounds like you have a lower intake manifold gasket problem. If you suspect a head gasket failure, you should test the compression. If the cylinders are all within 10% of each other, you don't have a headgasket problem.

RE: 93 s10 4.3 start up and idle problem
 

So I would need to remove the upper intake, and then there is a lower intake as well? Is this a difficult job, or can a shadetree mechanic like myself take care of it.The only reason I suspected the head gasket was that I didnt know of any other way the coolant might get into the exhaust. Thanks for the help.

RE: 93 s10 4.3 start up and idle problem
 

It's very doable. I just had the same thing happen on my truck (not as severe, but still) andI'm doing a complete write-up of the job for the CPI engine right now, but it's not quite finished. You can get it done in a weekend for sure if you've got all the tools and materials. This would include:

Good set of basic tools (deep and standard sockets and exts)

Gasket set (lower and maybe upper as well - felpro makes good ones that come with hight temp RTV)

Assortment of scrapers to clean off gasket material

Gasket remover (chemical)

Standard (not metric) tap/die set

Plenty of paper towels or rags

Penetrating oil

Probably one of those corny "GatorGrip sockets" for tapping out the bolt holes in the block, as the regular horizonal handles that come with tap/die sets are too long to use up against the ends of the block and the taps have square male heads which I could find nothing else that would grab onto them and be useful besides.

A shopvac with some small extensions/nozzles comes in handy, too.

Offset, racheting 3/8ths (I think, but check first) closed end wrench for the distributor bolt, which is a pain to get any other way and must be removed.

You might consider getting a set of internal fuel lines (aka - nut kit) for under the plenum as many people say they will leak if you reuse the originals.