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My truck is running bad

Z71Silverado

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Z71Silverado Enthusiast

Z71Silverado

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A year ago the tensioner for my ac belt seized and the small belt blew. I just had it replaced by my mechanic. The night I picked the truck up the truck threw an engine code fours hours later. The computer reads it as the mass air flow sensor. Since this has happened the truck struggles to run when idling. When I come to a stop sign or am slowing down the voltage drops so low that the truck shuts off half of the time. Another thing that I noticed since I got the truck back was that my horn now sounds like a foreign car horn instead of the usual chevy truck sound.

 

I unplugged the air sensor, still runs like poop with it unplugged. I pulled the relay sensor for the horn so a shorted out horn isn't the problem. Anyone else have any ideas?

 

I have ordered a new alternator and a jet mass air flow sensor. The current alternator is about 5 years old and it's a high output alternator that has to charge two batteries and two capacitors.



The truck is a 2004 silverado with a 5.3.

RyanbabZ71 Senior Enthusiast

RyanbabZ71

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Posted

Changed the topic title. Please review the site rules and refrain from the language. Thanks

Z71Silverado Enthusiast

Z71Silverado

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Well. I just found the problem with the horn. One of them was unplugged. Still running like poop though. Also, the mechanic is my father's long time friend and he doesn't charge me labor. That's the main reason as to why I'm trying to figure this out myself. I figure he dropped the air filter, maf sensor, air tube causing the sensor to break. Probably the reason it's throwing codes now. Would the alternator starting to go bad be why the voltage drops so low when idling or coming to a stop on the road? Without having to turn the compressor for a year the alternator wasn't working like it is now.

gmtech4 Senior Enthusiast

gmtech4

Posted
Posted

maf acting up or dirty will lower the idle ....stop jumping to conclusions about the alternator !!!!!

 

 

diagnose it properly !!!!!,,your makin me nuts !!!!

Chris Senior Enthusiast

Chris

Posted
Posted

Please don't make rob go nuts. When he goes nuts we have to give him warning points. We just calmed him down from the last incident so listen to his advice. He works on these for a living

 

Sent from my DROID RAZR MAXX using Xparent Red Tapatalk 2

txab Senior Enthusiast

txab

Posted
Posted

I would not install that JET MAF, install an OEM MAF. Sent from a jelly bean.

:withstupid:

Z71Silverado Enthusiast

Z71Silverado

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  • Author
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maf acting up or dirty will lower the idle ....stop jumping to conclusions about the alternator !!!!!

 

 

 

diagnose it properly !!!!!,,your makin me nuts !!!!

 

Almonds or cashews?

Z71Silverado Enthusiast

Z71Silverado

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Well. I replaced the MAF sensor and put a new alternator in today. The engine light went off at first but after a 15 mile test run the engine light came back on. The truck would not idle normally from the get go, even with the engine light off. The volts at idle run at 12.18 and sometimes it goes up to 13.80. The volts go up and down. This all started when I had the mechanic put the belt back on the air conditioner compressor. The voltage drops significantly when I hear a click(i'm assuming this is the compressor clicking on). It does this even if the air conditioner isn't running. I can feel the click in the evaporator hose. Could it be that my compressor is the problem here?

gmtech4 Senior Enthusiast

gmtech4

Posted
Posted

was the HVAC system set on defrost by chance ?

 

would you like the description and operation of the charging system?

 

changing the belt for the A/C does not cause any of these problems you seem to be having or think you have

 

what code is in the PCM?

 

stop me chris ,im feeling funny again,and not haha funny either!!!! lol

Z71Silverado Enthusiast

Z71Silverado

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No, the hvac was set at the vents and the fan speed was at 0. The truck ran great with zeros problems before putting the belt back on the air conditioning system. I haven't been able to bring it back to the mechanic to check what code it's throwing now. I won't be able to until Saturday.

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