You are here:

Chevrolet Repair/raw fuel in exhaust on 2004 Impala from defective coil pack

Advertisement


Question
replaced the catalytic converter and resonator on a 2004 Impala 3.8L. The engine was also missing bad and replaced plugs and wires. Still having problems with extremely rough engine idle so a friend checked it with a diagnostic machine. Found that a bad coil pac was another problem. But through all of these processes and driving for about a week found that now fuel has leaked into the catalytic converter and exhaust. Holding your hand at tail pipe there is no pressure. So now to remove total exhaust system.....can this be cleaned and reinstalled? Any advice? Please help!!

Answer
HI JAMES,I WILL ASSUME THAT THE ENGINE NOW RUNS GOOD..IF NOT THIS NEEDS TO BE ADDRESSED ASAP..
SO LETS SAY NOW THE ENGINE IS RUNNING GOOD,NO SKIPS. THE CONVERTORS CAN NOT BE REMOVED AND CLEANED.I DO NOT KNOW HOW YOU KNOW THAT THERE IS RAW FUEL IN THE EXH ???THIS WILL ALWAYS SMELL LIKE FUEL TO A POINT !!! IF THEY ARE PLUGGED THEY ARE BAD. HOWEVER IF THE EXHAUST SYSTEM IS PARTIALLY PLUGGED THIS CAR SHOULD HAVE LITTLE POWER ON THE OPEN RUN [SLUGGISH]LIKE A PLUGGED FUEL FILTER WOULD DO..TRY TO RAISE THE IDLE ABOUT 1800 RPM AND CK THE EXH PIPE LIKE THIS,I THINK YOU WILL FIND THAT THERE IS PLENTY OF EXH COMING OUT..IF YOU FEEL THE CAR IS SLUGGISH ON THE OPEN ROAD, REMOVE BOTH THE O2 SENSORS BEFORE THE CONVERTORS AND DRIVE IT LIKE THIS JUST FOR A TEST. IF POWER INCREASES THEN THE EXH IS PARTIALLY PLUGGED.IF NO DIFFERENCE THEN THE EXH SYS IS OK.[THIS WILL BE LOUD LIKE THIS DONT PANIC]. HOWEVER LETS SAY YOU GET A CK ENG LIGHT AND THE CODE IS FOR CONVERTOR EFFIENCY FAULT.. SO THIS MEANS THAT THE CONVERTOR WAS DAMAGED WHEN THE ENG WAS MISSING..HOWEVER IF THIS CAT IS NEW OR NEWER I WOULD BE LOOKING INTO THE OXYGEN SENSORS THEY DO NOT LIKE RAW GAS. THIS WILL ALSO CAUSE A RICH CONDITION IF THE O2 SENSORS ARE FAULTY. WHICH IF THEY WERE, THEY WILL POP THE CK ENG LIGHT ON. IF THIS HAPPENS CK THE CODES FIRST BEFORE DOING ANYTHING..LET ME KNOW HOW YOU MAKE OUT AND GOOD LUCK TO YOU,,,TOM..

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.