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Chevrolet Repair/88 c1500 305 tbi rough idle and no power

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Question
QUESTION: My 88 c1500 305 80k miles, had a idle that missed/surged. It wasn't that bad but aggravating. It hesitated when accelerated in gear, but wound out ok. I replaced, plugs, wires, cap, rotor, fuel filter, egr valve--it had a slight leak). Nothing helped. It even got worse with the new egr. I sprayed ether around the tbi and noted a small leak. I replaced the tbi gasket and while I was in there replaced the regulator diaphram, injector o-rings etc. Now it's even worse. Dies at idle sometimes. No power in gear but winds up decent in neutral. I pulled wires one at a time and could not find one that didn't kill the engine at idle. It doesn't have a fuel pressure test valve. I have ordered an adapter. Any other suggestions??

ANSWER: HI OLDMAN BILL,,OK WHAT YOU HAVE NOT TOLD ME IS HAVE YOU CHECKED THE TIMING ??? NO POWER COULD BE FROM THE TIMING BEING OFF OR LOW FUEL PRESSURE. IF YOU DO NOT HAVE A LIGHT TRY TO ADVANCE IT A LITTLE TURN THE DIST COUNTER CLOCKWISE ABOUT 1/4 INCH>>> RPM SHOULD INCREASE. LOCK IT DOWN AND DRIVE IT LIKE THIS..IF ENG KNOCKS YOU WENT TO FAR THIS IS GOING TO BE A DUMB QUESTION BUT IS THE AIR FILTER GOOD AND CLEAN ??? HAD TO ASK..SORRY..THE NEXT MOVE IF THE ABOVE IS OK AND FUEL PRESS IS GOOD, YOU WILL NEED TO GET THIS SCANNED AT A SHOP THAT HAS GOOD GM SOFTWARE..A BAD O2 SENSOR COULD BE TRYING TO LEAN THIS ENG OUT WAY TO MUCH,OR POSS BAD MAP SENSOR..YOU COULD UNPLUG THE MAP SENSOR AND SEE IF THIS HELPS THE RUNNING PROBLEM AT ALL,IF SO THE MAP SENSOR COULD BE BAD..
LET ME KNOW HOW YOU MAKE OUT..GOOD LUCK,,,TOM

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

QUESTION: I failed to mention that I replace the EGR at your suggestion on my first thread. Wasted $60 thanks. Yes, I'm not an idiot, the air filter is new.
I installed the fuel pressure test port. Fuel pressure was 3lb. Pulled the tank, replaced the pump, problem solved.

Answer
HI OLDMANBILL,I NEVER ONCE TOLD YOU TO REPLACE THE EGR VALVE... I SAID IT IS POSSIBLE THAT THIS COULD BE THE PROBLEM IF THE VALVE IS STICKY. YOU WROTE BACK TO ME AND TOLD ME IS WAS FOR SURE BAD....REMEMBER ???? I TELL PEOPLE TO REMOVE IT OR REMOVE THE VACUUM TO IT AND SEE IF THE VALVE STICKS LIKE THIS,, BEFORE YOU WASTE YOUR MONEY...YOU COULD OF REMOVED THE VALVE FROM THE ENG AND BLOCKED IT OFF WITH A PIECE OF METAL...I ALSO TOLD YOU ABOUT LOW FUEL PRESSURE..WHICH I WAS CORRECT ON..I NEVER THOUGHT YOU WERE A IDIOT.. BUT SOMETIMES PEOPLE OVER LOOK THINGS,SUCH AS AIR FILTERS. A BLOCKED AIR FILTER WILL HAVE ALMOST THE SAME EFFECT AS LOW FUEL PRESSURE..DON'T FORGET I AM HERE ON MY KEYBOARD NOT THERE IN PERSON !!!!I NEVER TOLD YOU TO REPLACE THE EGR VALVE..PERIOD...SO THIS IS WHAT HAPPENS WHEN YOU TRY TO HELP PEOPLE !!!THANKS ALOT..TOM  

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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.

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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

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MANY CUSTOMERS IN OUR BUSY SHOP.

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