v-6 issues

[pavementpounder]

First things first I have been a member at GMFS for a couple of years and at AOT since the begining that being said I have a 93' Chevy 1/2 ton 4x4 with the big 4.3 in it I have had a growing problem for the last week or so.

It has been idling like its only hitting on 5 cylinders and now when I get on the highway under normal acceleration it bucks real hard if I give it more gas and it downshifts it comes out of it.

it runs fine in town I have no check engine light or any stored codes and the engine is bone stock no mods of anykind with200k on the clock the last time I tuned it up was about a year and a half ago with all A/C Delco parts I also rebuilt the throttle body this spring.
it has a new Delco fuel pump and filter so other than mabe the need for another tune-up I am running out ideas..

 

[Mike]

Pull the plugs and see what they tell you.

 

[pavementpounder]

school me in plugs body and frame work I know but driveability is a weak spot for me..

 

[Mike]

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take a look at this

 

[pavementpounder]

Alright thanks the 2 I pulled looked normal but I will check the other 4 at the shop tomorrow

 

[99z28monster]

hmm sounds like it might be an issue with the cats. My old 94 had messed up cats and never threw a code so you never know of that. Did you replace the inline filter also when you did the pump? Check all your plug wires make sure none of them are burnt causing a short. Could be alot of things. The plugs are a great place to start also like someone already mentioned.

 

[pavementpounder]

It's cat delete but I haven't had a chance to look at it we have had some weather and the shop is full so it will have to wait but I'm gonna start with the plugs and see how they look.

oh and yes I did do the filter with the pump change.

 

[Ginger]

sounds like cap and rotor to me

 

[pavementpounder]

I changed the cap and rotor out this afternoon new Delco stuff it helped smooth it out some I am going to seafoam this weekend and change plugs.

 

[pavementpounder]

well I know you guys have been at the edge of your seats waiting to hear what I have found out.

I finally got a chance to pull the truck into the shop ans I swapped out all the plugs which appeared normal according to the chart in this thread and I also changed the plug wires I found burn marks on 3 of the wires from arcing now these are Delco wires that I just put on back in June but problem is solved.....