Oldsmobile/Buick Repair/1997 c3500 7.4L

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Question
Hi Tom its me again. Sorry had to take off for a week on a job. Now im back still cant get my dually to start.Recap so you can remember a lil about what happend. So it use to run pretty good. I work for the studios pulling traillers and such. One day Im pulling a trailler not to far and out of no where it starts hesitating running really rough loss of power. I finally make it to drop off trailler an d I got and turn off my truck unhitch trailler and hasnt started since. this is what I have done. At first I thought it mite of been a fuel issue so I replaced the fuel pump. then you asked me to check fuel pressure I did that and pressure was at about 56-60 wich was good.So after doing that now it would crank over fire up but then die out. Wouldnt stay running at all. Checked the trouble code gave me p0102. You asked me to check wiring and such so I did but nothing changed. I even went out and bought a new MAF but its still the same.I also changed plugs wires cap n rotor and still turn the key fires up but wont stay running. Checked the codes still p0102 comes up. I have also tried using Ether( quick start) fluid. Now for some reason when I spray the air cleaner box it keeps running until ther is no more ether then it stalls. Thats why I changed fuel pump thought it was lacking fuel but made no differance. The dually did fire up a coup[le of times when it did run I also tried disconecting the MAF when I did that the truck died out immidiatly. I dont know if it was suppose to do that. So it puzzles me that when I spray ether in the air cleaner it stays on untill it runs out of ether then it stalls. I have fixed many things on this truck before but this time im really stuck and dont know what to check or look for. You guys have helped me thru thick n thin before I know your the best hopefully you can guid me thru this one more time. If you need more info please just ask . I hope to hear from you soon when ever you get a chance. Thank you once again.

Answer
HI FRANK,,OK IAM GOING TO DO SOME RESEARCH ON THIS ONE CODE. I PROMISE I WILL GET BACK TO YOU ON THIS ONE AS SOON AS I HAVE SOME SOUND ADVISE.PO102 IS THE MASS AIR FLOW SIGNAL.ARE YOU 100% SURE THAT ALL THE WIRING TO THIS SENSOR IS ALL GOOD ??? [[[PERFORM THE TEST BELOW WITH THE LIGHT BULB ]]] THE REASON THIS WILL RUN ON STARTING FLUID IS YOU ARE PUTTING IT RIGHT IN THE ENG,,THE MASS AIR FLOW TELLS THE COMPUTER HOW MUCH FUEL TO INJ IN THE ENG,BY MEANS OF THE AMOUNT OF AIR IT IS TAKING IN. WHICH AT THIS POINT SOUNDS LIKE NOTHING OR HARDLY ANY AT ALL. YOU MAY EVEN HAVE A BAD PCM. DO YOU HAVE A SCAN TOOL THAT CAN DO DATA TESTING OR JUST CODE TESTING ?? BECAUSE THIS MAY COME DOWN TO SOMEONE DOING SOME DATA TESTING TO SEE WHAT IS NOT WORKING IN THE COMPUTER. CAN YOU CK FOR PULSE AT SOME OF THE INJECTORS..IT IS POSSIBLE THAT THE INJECTORS ARE NOT OPENING UP BECAUSE OF NO SIGNAL TO THEM. YOU COULD REMOVE A INJ HARNESS AND GET A 194 LIGHT BULB,BEND THE TANGS OF THE BULB OUT AND PUT THEM IN THE INJ HARNESS PLUG,HAVE SOMEONE CRANK THE ENGINE OVER AND SEE IF THIS LIGHT BULB FLASHES, IF SO YOU KNOW YOU HAVE SIGNAL FROM THE COMPUTER TO DO SO,IF NOT THE PCM OR WIRING HARNESS IS BAD...LET ME KNOW WHAT YOU FIND ON THIS AND I WILL CK MY COMPUTER TEST SITE ON THIS. GOOD LUCK,,  TOM.....
HI FRANK WELL I CHECKED MY MITCHEL  SYSTEM TODAY FOR THIS CODE AND NOTHING JUMPED OUT AT ME. THERE ARE MANY TSB'S [TECH SERVICE BULLETINS] ON THE MASS AIR FLOW HARNESS AND MASS AIR FLOW ITSELF.BUT YOU CHECKED ALL OF THE WIRING AND REPLACED THE MAF..SO LET ME KNOW HOW YOU MADE  OUT WITH THE ABOVE TEST..TOM

Oldsmobile/Buick Repair

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TOM SHEETS

Expertise

Can answer all questions pertaining to mechanics of GM cars from 1965 to present. I will answer questions from 6:00 am to 10 pm est.. I will not take diesel or paint questions. If this olds and buick section is maxed out you can get to me in the chevrolet section...

Experience

I have 30 plus years experience in servicing these cars. I can answer questions on carburetor, fuel injection,ignition systems, suspension, brakes and abs, cooling systems,a/c and heater,manual transmissions, rear differential and electrical system,charing system and battery. I am a Master ASE certified mechanic in all 8 categories: - Brakes - Heating and Air Conditioning - Automatic transmission - Clutches and Transaxle - Engine performance - Engine repair - Electrical - Steering and suspension I am certified for NYS inspection and clean air insp.

Organizations
ASE

Education/Credentials
I am a Master ASE certified mechanic in all 8 categories (see above) I am an Air Conditioning/Freon recycling specialist with ASE. I have at least 4 years of technical training and many hours of continuing education.

Past/Present Clients
many customers in our busy shop for the past 30 plus years

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