QuestionQUESTION: I have a 1994 g.m.c 1500 extended cab 4x4,with a 350 motor,with 150,000 miles.good truck,i'm the second owner of it had it about 8 months so far and no problems just changed the fuel fliter,put new spark plug in it about 2 months ago,but didnt replace plug wires.and brakes. and the guy who had it before me had no problems with it either he only had to replace the water pump.about two months ago,just after replacing the plugs,went to start it and it wouldn't even fire had power to radio,and lights,tap on the starter and 10minutes later started up. now about 2 weeks ago the weather started getting cold in illiniois and in the morning it would hardly want to turn over,but would on the first try,almost like the battery was goin dead,but it's got a good battery in it,then a day later when starting it nothing,no fire but had power to everything,so i replaced the starter yesterday and still nothing,had coil tested and the said the first test was alittle off,and the second test was good,replaced coil and still nothing,i can hear a humming sound buy the steering colum when i try to start it? dont know what to do?
ANSWER: Hi Kyle,
It sounds to me like the battery may be bad...even though it hold up to lighter loads like accessaries and lights it may not handle the high amperage of the starter. I would take it to a parts store or shop that had a load tester and have it tested or have some one check voltage with a multimeter while you are trying to crank if it drops below 9v then you batt is probly to low, it will not take a charge very well in the cold so bring it some where warm but not in your house as batteries emit hydrogen gas when charging. also, have someone verify that there is power to the starter when cranking. I would also recommend doing a volt drop test on the strter cables and starter solenoid. place one lead of the multi meter on the positive battery post and the other on the positive terminal at the starter have someone crank it and take your reading do the same for the ground cable (if the ground cable goes to the block and not to the starter take your reading at the starter housing...you shouldn't have more than 0.5vd (volt drop) on either cable....if you do you need to find where the resistance is. perform this test accross the starter relay as well. FYI when you read voltage on a multimeter all you are reading is the difference between two points. eg: between positive and negative = 12v. all your volt drops add up to the supply voltage (battery), for example, if you have a 3.0vd on one of your cables that means only 9 volts are making it to the starter. try these tests and see what you come up with. also, if its an automatic it could be the gear selector switch or if it is a manual it could be the clutch switch not closing.
sorry this is kinda long but hopefully it helps, good luck
Matt
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QUESTION: bought a new battery yesterday,and a ignition switch,and also a safety netraul switch,and still nothing cleand the ground wire that runs from battery to block off, also the the two wires that run to my netraul safety switch which is under my dash on the steering colum,steemed to have been messed with before i had the truck each wire has a little chuck out of the plastic coating which shows alittle of the copper? also some guy had all the same problems as me and it ended up being his high resitence ground wire???asked the guys at autozone and they had no clue? i also bought i voltage tester and gonna go threw everything tomorrow any other advice?
Answerhey,
my only other advice is to stop changing parts to find the problem...parts manufacturers are rich enough they don't need donations....find a manual for your truck and follow their procedures...failing that, take the info you have, devise a theory of what you think it could be, and prove that theory wrong or right. troubleshooting can be extremely frustrating if you're not systematic about it.
once you have some readings let me know what you find,
Matt
