Question ok here goes. I purchased a 1991 s10 blazer 2wd 4.3 tbi auto. I drove it about an hour and a half from where I bought it to where I live. I noticed that it idles quite high. first chance I got I brought it to a mechanic to see why it idled so high. the gasket under the tbi unit was broken and leaking. I purchased one and replaced it. after that it ran very poorly. so just for good measure, figuring it couldn't hurt I put new plugs, wires, dist. cap and rotor button on it to see if that helped. it didn't. so I replaced the coil. that didn't make any difference either. I have checked for spark. that seems to be good I removed the breather and the metal ring under it and the injectors seem to be pulsing like they should. the fuel pump comes on for the two seconds like I read it should when you first turn the key to on position. have tried cycling the key off and on for two seconds a few times before trying to actually start it. was told that was a way to check if the fuel pump was weak. didn't make a difference. pulled the plugs they were wet with fuel. while cranking it didn't belch through the tbi but when I let off it does. it lets out a big puff of white smoke that smells like gas. I have no way of checking fuel pressure or for checking codes. and I have checked and replaced all of the vacuum lines on entire engine. PLEASE HELP!!!!!!
Answer HI JEREMY,,WELL THIS SEEMS LIKE A RICH CONDITION FOR SURE..I WOULD NOT WASTE YOUR TIME CHECKING FUEL PUMP PRESSURE BECAUSE IT SOUNDS LIKE IT IS MORE THEN OK..BUT WHEN YOU SAY IT RUNS POORLY DO YOU MEAN IT IDLES POORLY OR RUNS POORLY ON THE OPEN ROAD..IF IT RUNS OK ON THE OPEN ROAD AND IDLES BAD LIKE LOPING OR HUNTING,UP AND DOWN NOT SMOOTH..IF THIS IS THE CAUSE THIS MAY HAVE A BAD MAP SENSOR...TRY TO REMOVE THE WIRING HARNESS TO IT AND SEE IF IT IDLES BETTER. NOT PERFECT BUT BETTER. IF SO IT IS BAD. THE OTHER POSSIBLE PROBLEM COULD BE THE OXYGEN SENSORS ARE BAD...THIS WOULD ALLOW TO MUCH FUEL TO COME INTO THE INJ'S..THE PULSE TO THE INJ'S WOULD BE LONGER I MEAN.. TRY TO UNPLUG THE OXYGEN SENSOR AND SEE IF THIS HELPS IT. IF YOU COULD SCAN THIS WITH A PRE OBD 2 SCANNER IT WOULD HELP ME A LOT TO KNOW WHAT IS GOING ON WITH IT..BUT I UNDERSTAND YOUR PROBLEM.....THIS SHOULD KEEP YOU BUSY FOR A WHILE GET BACK TO ME WITH MORE INFO OR YOUR FINDINGS..GOOD LUCK TO YOU,,,TOM..
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..
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.
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.