ok im stumped on this thing. got a 94 s10 with the w code 4.3 (cpi) whilever its cold it runs awesome, but theres an odor of gas... when it gets warm the idle sucks, theres black soot pouring out the tail pipe and there is no power. the plugs are also black which leads me to think its running rich. but im not farmiliar with chevys. please help asap
94 s10 CPI running like crap
- Thread starter gt500swim
- Start date
Tim C
Wizard
- Joined
- Jan 22, 2007
- Location
- Fayetteville
You should try to pull the codes because a lot of things could cause this. Coolant temp sensor or intake air temp sensors could be stuck reading cold (-40F) and it will flood and blow black smoke, but they will usually set a code.
My money would be on the injector tubes though. We call it the "spider" at work. If you pull the upper half of the intake plenum off you'll see why. There is one injector with a black plastic tube running from it to each intake port at the heads. Those tubes will crack and the thing will just spray fuel all over in the intake instead of to each intake port, causing one or more cylinders to run rich and flood. Also I think the fuel pressure regulator is inside the plenum on the injector and it can leak.
If you pull the valve out in the center of the upper plenum (I think its held on with 2 or 3 screws) you can sometimes look in the intake and see a "clean" spot of shiny metal while everything else has a dirty oily look to it, or you may see standing fuel puddled at the bottom. Those are signs you need to rebuild the injector tubes. I believe most parts stores will have an injector tube kit (might be called an injector nut kit also).
My money would be on the injector tubes though. We call it the "spider" at work. If you pull the upper half of the intake plenum off you'll see why. There is one injector with a black plastic tube running from it to each intake port at the heads. Those tubes will crack and the thing will just spray fuel all over in the intake instead of to each intake port, causing one or more cylinders to run rich and flood. Also I think the fuel pressure regulator is inside the plenum on the injector and it can leak.
If you pull the valve out in the center of the upper plenum (I think its held on with 2 or 3 screws) you can sometimes look in the intake and see a "clean" spot of shiny metal while everything else has a dirty oily look to it, or you may see standing fuel puddled at the bottom. Those are signs you need to rebuild the injector tubes. I believe most parts stores will have an injector tube kit (might be called an injector nut kit also).
VortecJeep
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- Joined
- Aug 24, 2005
- Location
- Concord, NC
I had a 93 CPI 4.3 in a Jeep I use to have. I had to replace the entire spider assembly.
bannerp
Well-Known Member
- Joined
- Dec 4, 2011
- Location
- Newland NC
Like Tim c said the spyder assembly has known problems for the lines cracking, ALSO there are two fuel lines that feed the spyder they are known to crack as well check these as well local parts stores should have these also they run about $20 bucks each and are a whole lot cheaper than a spyder.
NCDieselWrench
Well-Known Member
- Joined
- May 6, 2007
- Location
- Concord,NC
Two common problems are the fuel lines feeding the spider assm. crack causing them to leak and the other is the fuel pressure regulator could be leaking also. There is a round black plastic cap bolted to the top of the intake (you have to remove the plastic piece that says vortec on it to get to it) if you remove that plastic cap and look down into the intake if you see fuel pooling on the right side (drivers) of the manifold its the fuel lines, if you see fuel pooling on the left side (passenger) it probably the fuel pressure regulator. This is a really quick and easy way to tell if its something other than the spider injector. Good luck