breaking up at full throttle

[93h22cvc]

i have a 88 k5 350 tbi. at anything more than half throttle it breaks up and has no power. i changed the fuel filter and it is still the same. the pump is also pretty new. any suggestions

 

[DieselDan]

Well my first suspect was (is) the fuel pressure. You still might want to verify the pressure (regulator may be bad).

Next would be the EGR, then the ignition module.

 

[Thunder]

Have you Checked for trouble codes ?

 

[Can Can]

I've had similar issues in the past, and it ended up being bad plug wires. When's the last time you swapped in a new cap/rotor, plugs, and plug wires?

 

[Chaddy]

Yup....plugs & wires Im guessing because that happend to me.

 

[93h22cvc]

there isnt any codes. my plugs and wires are about 4 months old.the other thing is after this condition happens if i shut it off and immediatly start it back up it will run normal for a few minutes. what a pain

 

[93h22cvc]

the egr is not hooked up at the moment.

 

[Chaddy]

I still think its electrical.

 

[93h22cvc]

can anyone tell me what the unused wire coming from the distibutor area with a female connector is for.

 

[jeeptuff]

can anyone tell me what the unused wire coming from the distibutor area with a female connector is for.

Tachometer

 

[SUBFAN]

4 month old wires can still go bad....Check the coil too, it may be going south....

 

[diesel4me]

hope its not...

CAM LOBES??. ..every older GM V8 I had that a tune up didn't stop from breaking up at high speeds needed a camshaft..hope its not whats causing yours do do that...weak valve springs can let the valves float at high rpm and do much the same thing..you hear it "gargling" thru the intake at high speeds if it has bad cam lobes or bad springs..

I'm not very up to snuff on later vehicles with EFI,so its possible on your truck it might just be a computer or sensor problem,or a pick up coil in the distributor,ignition problem,etc..but maybe pulling the valve covers and watching the rocker arms, and seeing if all are moving the same amount might not be a bad idea,and save you lots of non returnable parts bought for nothing....

 

[Thunder]

Distributor module.