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Flat Work

Intermittent Check Engine Light.

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This spring, when I got the truck out, I had no alternator charge, and the CEL lightening bolt was on. I replaced the alternator, and batteries, and fixed the problem. The truck charges at almost 15 volts now.

But I still have a check engine light issue. But only while the truck is at idle to about 1000 rpm. As soon as the engine speed comes up above that, it goes out, and stays out. Until I come to a stop sign, red light, or just idle the truck. It's running fine. Starts fine, accelerates fine, and has its usual power. 

My DOT inspection is due next week. Is there any way for me to pull this code and determine the problem before hand?

 

Truck is an '04 CX-613. AC-427 engine. 344,000 miles.

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With fault code active , turn cruise control switch off. Push and hold the  Acel/Decel switch (either top or bottom) for about 3-5 seconds then release, the yellow lightning bolt will flash out a 2 digit code 

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5 hours ago, Mackpro said:

With fault code active , turn cruise control switch off. Push and hold the  Acel/Decel switch (either top or bottom) for about 3-5 seconds then release, the yellow lightning bolt will flash out a 2 digit code 

 

And I can do this with the engine running?

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I beleive shut the engine down turn the the key back on soon as the engine stops running!

 

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I have done it with the engine running, I believe the parking brake has to be set or no road speed detected.

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Posted (edited)

Okay, it's blinking 4-5. Which my research pulls up a problem with the VGT. 

When I bought the truck a year and a half ago, the VGT was stuck. I worked it loose with a small pry bar and penetrating oil, and it stopped throwing a fault.

 

Will this cause me to fail my inspection?

Edited by Flat Work

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At our shop  , on our DOT inspection forms , there is no mention of checking for fault codes. However , a state inspection or one done by a actual DOT officer may be different. I have heard of active ABS fault codes causing some trucks to fail  some DOT inspections at weigh stations.

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