You are here:

Chevrolet Repair/1999 suburban cylinder 5 misfire

Advertisement


Question
QUESTION: My suburban misfire sat idle only but have done complete tune up replaced the old shitty injectors with the new mfi ones brand new O2's. haven't replaced the knock sensors or cam or crank sensors. I was think valve so head needs changed. I did have to redo the adjustments on the cylinder 5 which fixed it for a day then came back.

ANSWER: HI MIKE,ARE YOU SAYING YOU HAD TO ADJUST THE VALVES ?? YOU SAY ADJUSTMENT ???? THIS WORKED OK AND THEN PROBLEM CAME BACK !!!  IF THIS IS THE CASE I WOULD REMOVE THE VALVE COVER AGAIN AND TAKE A REAL GOOD LOOK AT THE ROCKER ARM AND SHAFT ASSEMBLY..THERE HAVE BEEN SOME PROBLEMS WITH THE ROLLER ROCKERS ON THESE ENGINES...LET ME KNOW IF I DID NOT FULLY ANSWER YOUR QUESTION..TOM

---------- FOLLOW-UP ----------

QUESTION: Yes I had to adjust the valves cause the intake one was to tight and holding the valve open and flooding the cylinder with fuel I know when I had the valve cover off they didn't look worn or anything but I thought about swapping the rockers on cylinder 5 with a pair I have on a vortec head.

Answer
HI MIKE,I DO NOT UNDERSTAND HOW THE INTAKE GOT TIGHT TO BEGIN WITH UNLESS SOMBODY DID THIS BEFORE...ARE YOU SURE THE VALVE IS NOT STICKING IN THE GUIDE,HOLDING THE VALVE OPEN ???? CK TO MAKE SURE THE ROCKER ARM AND SEAT LOOK OK..IF SO I SUSPECT THE GUIDE IS HANGING UP THE VALVE STEM,THE VALVE STEM IS BENT...WAS THIS ENGINE EVERY HYDRO LOCKED ??? WATER IN THE COMBUSTION CHAMBER ??? THIS WILL BEND VALVES.IF VALVE IS BENT TIME FOR A NEW VALVE..YOU WILL NEED TO REMOVE THE VALVE SPRING TO CK THIS.. THIS HOWEVER IS VERY UNUSUAL TO HAPPEN..IF YOU DO FIND A PROBLEM WITH THE ROCKER ARM REPLACE IT WITH THE SAME YEAR AS YOUR ENGINE IS..DO NOT MIX MATCH.SOMETIMES THIS LIFT WILL BE DIFFERENT THAT YOUR EYE WILL NOT BE ABLE TO PICK UP. SHOULD NOT COST YOU MUCH..

Chevrolet Repair

All Answers


Answers by Expert:


Ask Experts

Volunteer


TOM SHEETS

Expertise

PLEASE READ ALL OF THIS BEFORE ASKING ANY QUESTIONS. IF THIS CHEVY SECTION IS MAXED OUT.YOU CAN REACH ME IN THE OLDS/BUICK SECTION. Will answer questions from 6:00am to 10:00pm all days [EST][[[ NO DIESEL OR PAINT QUESTIONS]]] will answer all 1965 to present QUESTIONS ON ALL GM'S on mechanics of these cars. Keep in mind i am not there in person i am going on what you are telling me !! PLEASE IF ASKING A QUESTION GIVE ME AS MUCH INFO AS POSSIBLE. THE MORE THE BETTER. SUCH AS YEAR,MAKE,MODEL,ENGINE SIZE. THIS WILL HELP ME HELP YOU. I will not be able to answer all questions because of some situations that i would really need to be there and see things for myself,such as electrical issues. In many cases i would need wiring diagrams. I can also give you an estimate on what the cost would be at our repair shop as an idea to help you. Keep in mind that my answer is ONLY MY ADVICE,ck with your mechanic as well.. >> THANK YOU, TOM..

Experience

I have been a ASE certified master mechanic for over 30 years and certified IN ALL 8 CATEGORIES,[engine repair,engine performance,auto trans,manual trans,clutches,steering and suspension,brakes,electrical systems,heating and air/cond. I am also a state CERTIFIED inspector for over 30 years. I do computer work [pcm]fault codes,pcm flashing,state inspection monitor readiness,repairs on exhaust,fuel service,[injection and carburetor,] charging system problems, running issues,alignments,frame problems,tire balance,struts and of course standard and anti-lock brakes.

Organizations
nys state auto repair industry and ase group.

Publications
N/A

Education/Credentials
high school,4 years of tech school,and many many hours of auto training with many gm classes and aftermarket training classes..

Awards and Honors
ASE MASTER TECH CERTIFIED IN ALL 8 CATEGORIES.NYS INSP LICENSE AND A/C CERTIFIED

Past/Present Clients
MANY CUSTOMERS IN OUR BUSY SHOP.

©2016 About.com. All rights reserved.