ok.. question for all.. im not a chevy buff.. but i got one in the shop yesterday.. been tryin to get it fixed.. c/e like wont stay off.. first i had a multiple cylinder misfire code... did a tune up.. plugs and wires.. 2 of the plugs were nasty nasty black.. looked like pre detonation.. reset the light.. took it for a drive cycle.. light came back on... this time i have a cyl. 1 misfire.. (p0301) and manufacture control fuel/air metering... new plugs .. new wires.. new ign. module.. please.. someone who knows chevys give me some ideas where to look from here.. this vehicle is a 1997 chevy blazer 4.3 .. thanks in advance

 

bump

 

i know its a dodge forum and all.. but wow.. this ia a shame.. i been working on this thing for 2 days now.. still cant figure it out.. replaced all i can think of.. plugs/ wires/ coil/ ign. module/ dist/ rotor/ cant seem to find the issue with the mult. cylinder misfire and the 'surging' .. cant find vac leak either... didnt realize no1 would even bother replying to a 'chevy' post

 

Is the EGR working and clean ?

 

Did you do any diagnosis? or are you just throwing parts at it?
Fuel pressure test?
Compression test?

 

do u know how to read a 4 gas analyzer?

thatll tell you where to look..

 

start with the fuel pressure as suggested... whatever the problem is, it is motor wide and not cylinder wide (as you probably already know) so focus on problems that affect the whole motor...

My son & I fixed his truck recently that had a bad coil pickup in the distributor... we chased our tails off and on for about a week until we decided to yank the distributor (per someones recommendation) and swap the coil... the pickups were cracked & basiclly fell apart when we took the cap covering the coil & pickups off...

another suggestion is to look at the crank & cam sensor signals, see if they are consistant or not, not 100% sure but I think that motor has a coil on plug setup, so you may look for anything that is in common to all of the coils too.

 

nah.. its not coil on plug.. its one coil for all of it.. i figured it out finally.. and sent it on its way.. compression is way low.. in 2 of the cylinders.. so its got valve problems for sure.. and the rings on cyl 5 are shot.. i told them they need to check the oil in these things more often.. and even change it once in a while.. the damn oil wouldnt even stick to the dip stick it was so broken down.. waiste of a good engine..

 

that sucks. well at least you figured it out... I'm happy to drill maint. into my kids heads... they'll never have that kind of problem.

 

As complicated as modern engines can be don't forget the basics.
I've seen lots of seasoned techs baffles for days because they get so in their heads and over think simple problems.