Random Misfire

[erikcouch]

Hey guys, Service Engine Light is on, so of course I take it down to the local Oreille's and have the code pulled....all it says is "Random Misfire". So naturally I change the spark plugs and wires...but...still doing it. It's also difficult to crank...it takes a minute to crank and when it does, it smells flooded....so I'm thinking it's a fuel issue, not a firing issue....Now I know I can check the pressure coming off the fuel pump to make sure it's putting out the correct psi, but from what I'm hearing, there's some kind of spider valve or something (not sure what it's called) to do with the fuel, that's under the manifold...apparently it's a common problem...Does anyone know what I'm talking about??? My Tahoe is a 2000 Z71 model 4dr - 4x4 - 5.7 engine. Thanks for any help.

 

[fjmichaels]

I'd check the o2 sensors as well.

 

[erikcouch]

Good idea! Thanks.

 

[project]

I have a 1996 tahoe. 5.7 vortec . same issue as other user. misfire but only on driver bank. new , cap, rotor, plugs , wires . and bank one sensor 2 o2 . Still misfire . new plugs but dont seem to be burning correctly. HELP.

 

[cesaralatorre71]

You have a intake gasket leak. Tighten the bolts on your Intake. You will notice your code will go away for a while then it’ll come back as the leak progresses. Hense. You have a gasket leak. The extra air going into the engine that is unaccounted by the Mas air flow sensor causes the random misfire. It is not your plugs. Or wires. Otherwise it would come up as a specific cylinder