Question about 1999 GMC Sonoma

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1999 sonoma I turn the heater to floor position and truck dies

I have the truck running, I turn the heater to the floor position and it causes the truck to die. It will start right back up,but again if I switch the heater to the floor only position, the truck dies.

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If the heater works in other positions than i dont know if I can help you. When you turn on the heater it opens a valve from the hot water in the radiator and diverts it to a small heater under the dash. If you do this in very cold weather you may be dumping a cache of cold water in the tube into the engine chilling the motor if it was recently started. if it has been running and heats fine, then you have either a straight electrical or electrical/mechanical flaw. the cable opening the duct to the floor could be pulling on some wire and causing it to misoperate. Follow the cable to the vent and see if there is anything in the way. and yes you will have to stand on your head with your feet on the head rest to track it down.

Posted on Feb 12, 2012


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SOURCE: 1999 gmc sonoma

push the truck into a lake

Posted on Jul 25, 2008

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SOURCE: Fuel pump fuse keeps popping

You have a short to ground or the pump is starting to go bad. You can run a seperate wire from the hot side of the fuse to your pump to see if it is the pump or if you use an ohm meter to check the wire and the pump. Get's a little technical though.

Posted on Jun 02, 2009

michigan man
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SOURCE: Heater does not work

first make sure you have anti-freeze in it and there is no air bubbles in the system and if you are talking about the blower motor make sure all of wires are good and the temp limited switch next to the blower motor is good give these websites a try and if all fails stop by your local library and get your hands on a Haynes auto repair manual for your truck wish you the best of luck Michigan Man.

Posted on Jan 31, 2010

  • 90 Answers

SOURCE: My 1995 GMC Suburban dies every time I turn on the heater or air

sounds like A/C compresser is seized

Posted on Mar 08, 2010

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SOURCE: I have a 1999 GMC

you may have bought a bad altenator,it's happened before. you're battery may have been bad and you bought an altenator instead,did you have both checked? suggest you have your battery checked because the old altenator may have overcharged your battery and it's bad now due to a new altenator. autozone or advance auto parts check both for free. are you near one? have it checked to be sure. are you having to boost it off every block you drive? it may be a different issue thats come up. it may be a bad idle control sensor thats making it die. when you hit the brakes hard,does it want to die? idles fine,until you drive it and dies down when hitting your brakes at red lights. it may be that. somethings making it die. are your guages doing the same thing?crazy? charging issue. dying issue may be different though. idle control sensor,i suggest,if diagnosis fits,replace it for around $20.00 for part. replacement only requires removal of 2 screws and one electrical plug in to it. thank you for choosing we are here 24/7 7 days per week every one on planets on vacation at the same time!!

Posted on Jan 13, 2011

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1999 gmc sonoma

push the truck into a lake

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