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Chevrolet Repair/Chevrolet c1500 fuel pressure port locate

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Question
QUESTION: Does my 1988 305 tbi have a fuel pressure test port?

Truck idles rough--lopes; hesitates. Seems to do a little better when engine is warm. Runs better when I accelerate on the road. I have replaced plugs, wires, rotor, air and fuel filter. Any suggestions appreciated.

ANSWER: HI BILL, YES IT SHOULD IF YOU LOOK BEHIND THE TBI THE FUEL LINES COMING UP TO THE THROTTLE BODY THERE SHOULD BE A TEST PORT ON THE LARGER OF THE 2 LINES. LOOKS LIKE A TIRE VALVE STEM CAP.BUT IS DO NOT THINK THIS IS A FUEL PRESSURE PROBLEM !!!!SOUNDS LIKE POSSIBLE STICKY EGR VALVE OR BAD MASS OR MAP SENSOR.  CAN YOU TELL IF THERE IS A CYLINDER MISFIRE FIRST OFF. DO A MILD BRAKE STAND [FOOT ON THE BRAKE AND RAISE THE IDLE IN GEAR TO ABOUT 1500 RPM] IS IT SMOOTH OR IS THERE A SHAKE ?? IF THERE IS A SHAKE YOU HAVE A CYLINDER MISFIRE. CK WHICH CYLINDER IS SKIPPING,THIS COULD CAUSE A LOT OF YOUR PROBLEMS.. IF NOT GET BACK TO ME WITH MORE INFO,OR IF YOU DO NOT KNOW HOW TO CK WHICH CYLINDER IS MISSING.. LIKE TO HELP YOU OUT..GOOD LUCK TOM..

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QUESTION: TY. I will do and update in a day or two.

ANSWER: HI BILL,OK,, LET ME KNOW HOW THIS GOES...TOM..

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QUESTION: Hi Tom, Thanks. EGR definitely bad. Diaphram leaked when vacuum tested. Now I have original problem: Just a little miss on idle and hesitation when I accelerate. I have now replaced plugs, dist cap, rotor, wires, fuel filter, and EGR valve. No codes. Any suggestions appreciated. Bill

Answer
HI BILL,CAN YOU FIND WHICH CYLINDER HAS THE MISS ???? THIS IS MORE THEN LIKELY YOUR PROBLEM..PULL ONE WIRE OFF THE DIST-CAP WHILE RUNNING ONE AT A TIME UNTILL THERE IS NOT ALOT OF CHANGE OR NO CHANGE IN THE RPM. ONCE YOU FOUND THAT YOU FOUND YOUR MISS IN THE ENGINE. MAKE SURE THE TIMING IS SET OK AS WELL. POSS SCTRETCHED OR LOOSE TIMING CHAIN. LET ME KNOW HOW THIS GOES FOR YOU, GOOD LUCK,,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.

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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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