I posted a thread recently about a cylinder 3 misfire.. the code will not go away and im not sure why its on.. it seems to have decent power.. it just seems to shift funny at times and doesnt have bottom end.. i am also having problems with starting.. i was told that could be the fuel pressure regulator.. im gonna replace an injector and the fuel pressure regulator.. im looking for advice.. what else could be wrong with it?/
Thanks BRIAN

 

I wouldn't think it's the FPR. When those let go they leak internally (it is INSIDE the manifold) and they flood out cylinder 6 and 8 usually. It can be a clogged poppet. It can also be a bad distributor cap. The "crab cap" the Vortecs use has conductors that cross over inside of it, and that makes them prone to break down with carbon arching. On your cap look at where the #3 spark comes from to get to the driver side and ou'll see what I'm talking about.

If you do need to replace the FPR or a poppet, buy the whole retrofit Multec-II assembly. It doesn't have poppets and is superior to the old design because of it.

 

If it's always on cyl#3 you might check your injector on that cyl.

If it was a random engine cyl misfire I would say it could be several diffrent things.....but the fact that it's on #3 all the time.....make sme think injector.

 

i replaced the cap and rotor and it didnt make a difference.. im gonna change the fuel pressure regulator and check the injectors.. im not sure what else to do..

 

I had the same code once on an '82 and it was the #3 injector. It just stopped working one day. I tried replacing the cap, rotor, plugs and wires and no change. Changed the injector and it ran fine.
The truck ran ok at speed but was weak accelerating and took a couple hundred more RPM to cruise at 70. Gas milage sucked too.

 

thanks for the help.. So do you think the injector is bad.. i was gonna replace it anyway.. im glad that i found someone that has had similar problems as i did.. im gonna check the injector then.. it must be clogged or something .. thanks for the help
BRIAN

 

I couldn't see anything wrong with it but changed the injector anyway and that fixed mine. Hope it does for yours too.

 

The MULTEC 2 upgrade is only like $266 and comes with anew FPR, buying an individual imjector is like $80-$90.

Here is the kit I am talking about(scroll to bottom)
http://www.pacificp.com/forum/viewtopic.php?t=981

Comparison of MUltec 2 and stock popets on top of each other(scroll down)
https://www.performancetrucks.net/fo...d.php?t=356743
For under %300 you get 8 new UPDATED true MPFI injectors with a new FPR. These are much better than the old poppet style injectors.

peace
Hog

 

I didnt get ur post until today.. Yesterday i changed my fuel pressure regulator and replaced cylinder 3 and 6 injectors. It runs a lot better now.. I got all the power back that i lost. I was just wondering what makes the Multi-tec 2 upgrade so much better than the stock injectors.. the more the info the better..
thanks
BRIAN

 

also,, i see that many of you put marine intake manifolds on instead. is there a reason for that.. do you get better performance out of them? how much do they cost and what are the benefits and disadvangtages..
thanks
BRIAN