How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Dan Your Own Question
Dan, ASE Certified Technician
Category: GM
Satisfied Customers: 2270
Experience:  20+ years in automotive repair work
Type Your GM Question Here...
Dan is online now
A new question is answered every 9 seconds

Where is the egr valve on a 2003 yukon denali xl 6.0

Resolved Question:

Where is the egr valve on a 2003 yukon denali xl 6.0
Submitted: 8 years ago.
Category: GM
Expert:  Dan replied 8 years ago.
This vehicle does not have one.
They had them on some of the 99-01 years but stoped in 2002 on these engines.

Are you having a particular problem?
Customer: replied 8 years ago.
Yes i have codes that say vacume leak and cat converter possible problems. The truck idles great and runs fine but if you give it more than say 4 to 5 grand it starts to sputter and spit and backfire. I have replaced the mass air flow sensor as the code stated, new pluges and wires. cleaned the throtle body by removing and completly cleaning. Any suggestins?
Expert:  Dan replied 8 years ago.
What code #'s did you get?
Customer: replied 8 years ago.





Expert:  Dan replied 8 years ago.
P0430 is the exhaust converter code that can be caused bythe P0300 misfire code,
The P0135 is a heated oxygen sensor code.
P0101 is the mass air flow sensor code.
P0300 is a misfire code.

I would start out by checking the fuel pressure. Spec is 55-62 psi while the pump is running and the engine off or the fuel pressure regulator vacuum line unpluged.
A weak pump or a clogged fuel filter can set a mass air flow code and a misfire code which can also cause the converter to have problems.

Also may need to check back pressure on the exhaust to see if it is clogged. A clogged converter can cause the codes to set also.
Customer: replied 8 years ago.

I have already checked the fuel presure it was alittle low so i changed the fuel filter and that corrected that. I have 268,000 and im the orignal owner. I have always maintened this truck very well and its all highway miles.


I also thought the p0101 was a maf or a map.


since i replaced the maf could it be the map.


I dont mind doing the cats but at 1600.00 i would rather try the cheeper options first.



Expert:  Dan replied 8 years ago.
The p0101 is a MAF(mass air flow) sensor code. Other problems can cause that code to set.
You may want to put a fuel guage on it and see what the pressure do when its acting up.
You can look into some aftermarket converters at a fraction of the cost.
Dan and other GM Specialists are ready to help you