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99 dies when you let off the throttle?

jw7054

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jw7054 Enthusiast

jw7054

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I have a Chevy 99 z71 4x4 LT. It has had an egr code that comes on and off since I bought it like 6 years ago. I have cleaned it and it turns the code off but it ends up coming back, I haven't checked the codes since it stalling out. The problem is when you let off the throttle it starts to lurch and when you are braking going up to a stop it dies. You put it in neutral and it starts after no more then 3-4 seconds at most. It has 183k. The problem isnt Everytime. Sometimes it stalls, sometimes it almost dies but doesn't go below 500rpm. Sometimes there is no problems coming up to a stop. It doesn't start hard, starts right up, cold or warm. It doesn't pop or smoke. There aren't any mods done to the truck. So what do you think it could be? I was told maybe a vacuum leak and I have thought about changing plugs and coils but haven't yet. Any ideas or help is appreciated. Thanks!

 

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sefiroxx Enthusiast

sefiroxx

Posted
Posted

Check/clean MAF sensor. Spray brake cleaner around air plenum and hoses to see if engine speed changes. EGR might be clean, but the pintle coil/motor might be irratic and subject to impact of heat and vibration and may need replacing.

 

How is the mpg, excess air (introduced after the MAF would cause a lean condition.

 

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jw7054 Enthusiast

jw7054

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Okay I scanned it today and here is all I got

p040

po50

p1404

All egr related codes. I changed the spark plugs and it still lurching but I haven't had it stall out yet.

 

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