rough idle, where is the EGR valve on a 2003?

[teakman]

I have the Haynes manual for the 99-06 Chevy's and it clearly has a picture of the EGR valve next to the oil cap, but I be damned if I have one in that location. I've looked high and low on both left and right sides to no avail. Where is this thing ??

2003 Tahoe 5.3L

Symptoms are a rough idle when cold, racing up to 1500 rpm's and down to 500 rpm's. Seems OK after warmup. I'm getting trouble codes P0171 and P0174 which are lean codes on bank1 and bank2. No vacuum leaks that are obvious. I've replaced the fuel filter, MAF sensor, air filter. I've checked the fuel pressure and it is great according to the manual (around 52 at startup and 42 when running). EGR ?

Thanks

 

[teakman]

no egr valve on 2003

My own followup here ....

Called the dealer to order an EGR and the don't have it listed ... so I guess the answer is that the 2003 doesn't have an EGR. My friends 2005 doesn't seem to have one either so I guess they are no longer needed.

Still have my rough idle when cold and am hoping it is something other than the manifold gasket.

 

[Target]

Got the same problem in my 02 tahoe. I have a flashing Check Engine Light on a cold start. I read a "fuel too lean banks 1 & 2" as well. As well as multiple MIS-fires codes. I have replaced both O2 sensors (banks 1&2) and the coolant temp sensor. Helped for a while. Now same problem.

Now I learn that the manifold on the 02 is made of plastic. After some age & miles it allows air in when cold. When the engine heats up, the plastic expands and all is well. My local guy gave me an estimate of $200.

BTW...I have a flex fuel engine and it does not have an EGR valve.

Good luck.

 

[Target]

Got the same problem in my 02 tahoe. I have a flashing Check Engine Light on a cold start. I read a "fuel too lean banks 1 & 2" as well. As well as multiple MIS-fires codes. I have replaced both O2 sensors (banks 1&2) and the coolant temp sensor. Helped for a while. Now same problem.

Now I learn that the manifold on the 02 is made of plastic. After some age & miles it allows air in when cold. When the engine heats up, the plastic expands and all is well. My local guy gave me an estimate of $200.

BTW...I have a flex fuel engine and it does not have an EGR valve.

Good luck.

Follow up...

Now the weather is getting colder, the rough idle stated again. I had the manifold gastek changed ($80 part) and it runs like new. Picked up a couple of MPGs and HPs. Be sure to clean your intake while you have it disassembled.

Good Luck,

Target