96 suburban code 304

[mr moose]

what i have here is a 96 suburban 5.7 4x4 1500 throwing a code 304. i know that means cyl 4 has an issue. i have tryed all the norm . plugs,wires,cap,rotor. the spider was replace a year ago. the cats were replace three months ago. it will only show up on the highway at around 65mph. the whole car shakes and i know its about to throw the code. i found if i smash the gas down the shaking stops and the car will accelerate as normal? or i can let up all together and wait a few seconds for it to stop and then i can go agian. any help would be great. thanks. mark.

[mr moose]

not one of you guys can help?????

[MT-2500]

Originally Posted by mr moose

not one of you guys can help?????

It is Sunday all day today just.
Hold on and there will be people to help


What was wrong with cats?
Good ac delco parts used with tune up?
Any other codes?
How is fuel pressure and camshaft retard setting?
Any aftermarket air filter setups?
If just moving gas pedal brings it out of it i would run a close check on the tps sensor.
Also back then there was some 02 sensor wiring problems that would take out no 4 cylinder but that usually was a full time miss.
Any misfires at idle?
A good full scan with a engine capable scanner and sensor read out at time it does it may help pinpoint problem.

[mr moose]

i was having a code 300 multi cyl misfire i was also having a catylst inefficiency code do not remember code. i replace cats and that stoped and now this started almost right after. i forgot to list, when started first thing in the morning and i go to leave, it falls on its face like an old carburated car would back in the day. i replace fuel pump last summer the wires to the plug melted so i did the whole thing. and yes i used all ac delco stuff. i have not checked cam retard. im starting to think i have a sticky valve or maybe new injecter failing. im not sure. im tired of spending money chasing the ghost!! any other ideas would be great. as for sunday thats just another work day here . thanks. mark.

[MT-2500]

Originally Posted by mr moose

i was having a code 300 multi cyl misfire i was also having a catylst inefficiency code do not remember code. i replace cats and that stoped and now this started almost right after. i forgot to list, when started first thing in the morning and i go to leave, it falls on its face like an old carburated car would back in the day. i replace fuel pump last summer the wires to the plug melted so i did the whole thing. and yes i used all ac delco stuff. i have not checked cam retard. im starting to think i have a sticky valve or maybe new injecter failing. im not sure. im tired of spending money chasing the ghost!! any other ideas would be great. as for sunday thats just another work day here . thanks. mark.

We have gave you ideas .
Check them out and see where they go.

[mr moose]

do you need to calibrate the tps???? if so how is that done please. mark.

[david jones 2345]

Originally Posted by MT-2500

It is Sunday all day today just.
Hold on and there will be people to help


What was wrong with cats?
Good ac delco parts used with tune up?
Any other codes?
How is fuel pressure and camshaft retard setting?
Any aftermarket air filter setups?
If just moving gas pedal brings it out of it i would run a close check on the tps sensor.
Also back then there was some 02 sensor wiring problems that would take out no 4 cylinder but that usually was a full time miss.
Any misfires at idle?
A good full scan with a engine capable scanner and sensor read out at time it does it may help pinpoint problem.

had simalar problem replaced ignition module hope it helps

[david jones 2345]

Originally Posted by mr moose

what i have here is a 96 suburban 5.7 4x4 1500 throwing a code 304. i know that means cyl 4 has an issue. i have tryed all the norm . plugs,wires,cap,rotor. the spider was replace a year ago. the cats were replace three months ago. it will only show up on the highway at around 65mph. the whole car shakes and i know its about to throw the code. i found if i smash the gas down the shaking stops and the car will accelerate as normal? or i can let up all together and wait a few seconds for it to stop and then i can go agian. any help would be great. thanks. mark.

did all that cam sesor crank sensor cap wires plugs was the ignition module fis of the ign coilhe side on tnaly died lost spark replaced it timed cam sensor and crank runs like a bear now hope it helps about 80 bucks sitsof the ign coil hope this helps
on the side