Chevrolet Repair/testing

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Question
Hi, and thanks in advance for your help. I need to test my TPS. My vehicle is a 1997 Chevy Blazer LS, 4dr, 2wd, 4.3L Vortec, AT. I was able to find some info, but it said how to test tps with 3 wires, mine only has 2 wires. Reason for testing; poor performance, poor fuel economy, weird trans shifting...

Answer
HI ANDY, ONE WIRE SHOULD HAVE A 1 TO 5 VOLT REFERENCE FROM THE PCM AND THE OTHER SHOULD BE A 12 VOLT SUPPLY. GROUNDS THROUGH THE CASE. I DO NOT FEEL YOUR PROBLEM IS IN THE TPS..HAVE YOU TUNED THIS ENGINE RECENTLY ??? USUALLY WHEN A TPS GOES BAD IT BOGS DOWN AT TAKE OFF OR A FLAT SPOT AT SAY 30 MPH OR SO..THIS IS THE NORM FOR A TPS. IF IN FACT YOU FIND IT IS BAD,REPLACE IT AND TURN THE IGN ON,THROTTLE CLOSED ALL THE WAY AND SET THE REFERENCE SIGNAL TO .5 VOLTS WITH A VOLT METER.IF NOT THE TPS,,,I WOULD CK THE MASS AIR FLOW SENSOR FIRST JUST UNPLUG IT AND SEE IF THE RUNNING ISSUES GET BETTER,NOT PERFECT BUT BETTER. IF SO THE MASS AIR FLOW IS THE FAULT. HAVE YOU CHECKED FOR ANY CODES IN THE SYSTEM YET ?? THAT WOULD BE MY FIRST STEP. HOWEVER YOU WILL STILL NEED TO DO THE MASS AIR FLOW TEST LIKE I SAID BECAUSE MORE TIMES THEN NOT THE PCM WILL NOT SET A CODE FOR A FAULTY MASS AIR FLOW. YOU WOULD NEED A SCAN TOOL THAT CAN GIVE YOU DATA READOUT TO CK THIS.. THIS MAY ALSO CAUSE LATE SHIFT POINTS...[[[POOR FUEL ECONOMY >>> PLUGGED AIR FILTER OR FAULTY O2 SENSORS,,]] THIS WILL HAVE A CODE FOR IT...DO NOT FORGET TO REPLACE THE FUEL FILTER AS WELL IF YOU HAVE NOT ALREADY..LET ME KNOW IF YOU HAVE ANY CODES OR GET BACK TO ME WITH MORE INFO..GOOD LUCK,,,TOM.
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PS,HI AGAIN ANDY,I AM AT WORK  AND I THOUGHT I WOULD LOOK THIS SYSTEM UP AND ALL OF MY COMPUTER SOFT WARE IS TELLING ME THIS YEAR BLAZER HAS A 3 WIRE TPS SENSOR NOT 2.  DID YOU CK THE HARNESS AND TPS SENSOR TO MAKE SURE A WIRE DID NOT BREAK OFF ???  

Chevrolet Repair

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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.

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.

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