1. 1987 f-150 4x4 with 4.9 ,4speed granny,short box.i've got it almost done,but i can drive for about 45 min to an hour and the truck wants to start bogging dowm until it stalls. i'm getting KOER codes 33 and 42.other codes were present,but i got those taken care of.this is what i've replaced so far;starter,starter relay,spark plugs,wires,distributor cap,rotor,pick-up coil in distributor,ignition coil,ignition control moduale,eec relay,fuel relay,map sensor, pcv valve,oxygen sensor, temp sensor,idle air control valve,tps,throttle body base gasket,TAD solenoid,TAB solenoid,EGR solenoid,all fluids,all filters,most vac hoses,low pressure fuel pump,high pressure fuel pump.all within the last six months.eliminating one to three codes at a time.all that is left are 33 and42.would these codes cause my problem with it bogging down after driving it for 45 min? any and all help would be great,thanks.

 

i'm just wondering if anybody had a problem like this.the engine want to act like i'm pulling a heavy load,but i'm not and i'm on level ground.any help would be great.thanks.

 

i've pulled the EGR position thing off and found a brownish residue on the plunger shaft ,it made it stick some ,so i cleaned it off. would this help clear the code or what?

 

i was told by a friend that if i clean up the EGR valve and tube it should clear up both codes.i think i'll try that in the next couple of days.i seem to be the only one posting on this thread,but i'm venting through here rather then on my truck. thanks.if anybody has other sugestions,i'd like to hear them.it might not sink in fast,but i'll listen.thanks again.

 

Code 42 is system rich so I would check the fuel pressure regulator and also check for a restricted exhaust flow.
just my guess.

 

thanks for the info lazy k,i'll check into it.

 

clogged cats -catalytic converter? had a few vehicles do this -no power like it was struggling to just run on level ground-might be worth a check

 

no cat on this truck.i'm looking into cleaning/changing the EGR valve.a lot of people i've talked to agreed this is my problem.i've checked/changed most everything else.thanks for thinking of other solutions to the same problem.