So I've just returned from an almost coast to coast to coast road trip during which I have noticed the beginnings of white smoke at idle. Not a lot and not all the time. I also had the SES light come on...for about five minutes the after the light came on, I had an almost 300-400 RPM surge at idle. Since then, sometimes the truck idles fine and sometimes it idles rough. At any rate, I took the truck into the dealer today to have my balance rates checked and the codes read.

As far as the balance rates go, they told me that they were unable to read them, probably because of a problem with my truck. What the problem was they couldn't tell me. As for the codes, they read a P0101 Mass Air Flow Sensor, a P0404 EGR Open Position Performance, and a P0499 EGR Solenoid Control Circuit.

First off, I am hoping you folks can tell me why they wouldn't be able to read my balance rates? And second I am hoping you can tell me what I need to replace or fix to take car of these codes?

This is on the truck in my signature, which is and always has been stock. It is unfortunately a California emissions LB7. I appreciate any help you guys can offer me. Thanks!

The most common problem with the Mass Air Flow Sensor is when an oil-type filter (K&N, etc.) is used and over-oiled. The oil will pull through the filter and coat the MAF. The solution is easy (and cheap!): buy a can of MAF cleaner, and give it a good rinse.

As for why they couldn't read balance rates, it could be any number of things. My guess is they didn't know how to do it or messed up somehow.

Someone else will have to help with the EGR... mine was causing surging at idle, so I disabled it with EFILive and ripped it off the truck. Just a guess from the P0499, you might want to look for loose connections near the top of your fuel filter. That is where most of the EGR solenoids live.

I've never used anything but the stock air filter, but I will pull and clean the MAF. I'll also take a look at the solenoids. Is there any way to tell if or which one of these is bad?

You can probably test them with a 12V jumper and listen for a click, but that doesn't mean they are opening all the way (or at all). I forget which solenoid is the EGR solenoid, but I'd start with that one. Try searching for EGR on here, you might find what you need.

I did some searching and got in touch with user maxinDixon from the forum. He was able to point me in the right direction with the solenoid that matches those codes. I ordered it today, so hopefully it will be the fix for the problem. Thanks for help!

I did some searching and got in touch with user maxinDixon from the forum. He was able to point me in the right direction with the solenoid that matches those codes. I ordered it today, so hopefully it will be the fix for the problem. Thanks for help!
maxinDixon was the guy who helped me get the EGR disabled on my truck when it was surging at idle. Turns out that you can't set the EGR parameters to their max/min values or the computer tweaks out... long story short, he seems to know the EGR system inside and out. I'm sure he'll get you going!