ofcmlong

I have a 96 Blazer 4.3 4dr. I have noticed that once in a while the fuel pump won't kick on and when that happens the car won't start. I also noticed the service engine soon light wasn't coming on at start up but it does now.

I think its a connection some where.

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I Just Got Out Of The Shop With The Same Problem. The Fuel Pump Is Going Bad And Needs To Be Replaced. As For The Check Engine Light Is It On All The Time?

Jethro_Canada

When it doesn't start smack the bottom of the tank with a rubber hammer, if that works look at a fuel pump. Also you might want to check the connector behind the bumper and make sure it has good connection, mine had the weather packing cracked and the connection was clicking in and out.

ofcmlong

The check engine light works fine now. It comes on at start up and goes off whe it should.

When the car is running it runs perfect. I was just checking it out and also found out that when I can get it to where it won't start right up, if i turn the key off and right back on the pump comes on. Also if, when it won't start right up, if I keep cranking it, eventually the pump kicks in and starts up. It seems like the first cold start up it runs fine and then if I shut it off, sometimes, it the pump won't kick in right away.

I heard there was a problem with gas caps with the blazer and that the system would lose vaccum or something like that.

Any more thoughts?

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You Might Have A Bad Pump Relay. In The Back Of The Glove Box There Are Three Relays, Im Not Sure What One Controls The Pump But An Easy Way To Check Is To Remove The Cover And Turn The Key To On. You Should Hear The Relay Click.click And No Pump- Bad Wire Or Fuel Pump, No Click -bad Relay Ill Check And See Iff I Can Find What Relay It Is. Hope This Helps

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Hey Forgot To Mention After I Got The Pump Out I Took A Small Screwdriver And Moved The Fins Inside After I Hooked It To The Wiring Harness The Pump Started But Ran Really Ruff. Yours Might Just Be On The Verge Of Total Failier.

ofcmlong

The latest. I turned the key, heard the full pump come on yet it still took a long time for it to start up. I would say it has to be electrical.

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If The Pump Is Running Do A Pressure Test And See What Psi The Fuel Is At. The Hard Starting May Be From Low Fuel Pressure.

ofcmlong

I just got it back from the dealer. They seem to think it was the fuel filter. I guess only time will tell but so far so good.

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IM DONT THINK THE FILTER WOULD CAUSE THE PUMP NOT START. THAT BLAZER HAS TWO IN TANK FILTERS ONE ON THE BOTTOM OF THE PICKUP AND ONE RIGHT ON THE PUMP THE OTHER ONE IS A INLINE ON THE FRAME RAIL.I JUST HAD A 96 BLAZER 4.3 4 DOOR IN THE SHOP ONE DAY AGO, HIS PROBLEM WAS THAT IT WAS RUNNING WEIRD, WHEN HE WENT OUT THE NEXT MORNING IT WOULD NOT START. WHEN WE GOT IT HERE THE FUEL PUMP WAS NOT TURNING ON. AFTER RULING OUT THE RELAY WE TORE OFF THE TANK AND FOUND THE PUMP THE PUMP WAS JAMMED. I TOOK A SMALL SCREWDRIVER AND TURNED THE FINS INSIDE. I THEN PLUGGED IT BACK ONTO THE WIRING HARNESS AND IT DID START BUT WAS VERY GRINDY. THE ONLY OTHER THING I COULD TELL YA IS THE THE MAIN PLUGS ON TOP OF THE TANK HAVE A HABIT OF CORRODING AND FAILING. HOPE THIS HELPS KEEP US INFORMED.

ofcmlong

Here is what has been done thus far. The whole tank was replaced because of a leak. The fuel filter was changed. I haven't check the fuel pressure yet because it is under warranty but I am losing faith in the dealership quickly. I have noticed that some times the service engine light comes on at start and goes off and sometimes it doesn't come on at all.

I can hear the pump turn on when I turn the key to the on positon. I can hear the pump shut off when I turn the key off. I can also hear what I think is the pump while its running.

The start up problem doesn't happen all the time. For example last night I moved it from in front of my house to the back in my garage. About 2 hours later I went to move it out of the garage and it was really hard to start. I did the same thing today and the same result. But after that it starts up just fine. It starts just fine when I get in it in the morning after sitting all night.

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Ill do some checking tomorrow and get back to you.Im baffled

ofcmlong

Thanks. I've been trying to pay attention to anything else that was out of place but everything else seems fine.

ofcmlong

More. Seems it only acts up after it has been sitting for more then a half an hour. If I start it up right after shutting it off it is fine. If I let it sit overnight it is fine.

Does anyone think I am looking at the Fuel Pump and that the SES light is just acting up?

ofcmlong

Help!!!!!