If I drive about 60 miles, which is a change in elevation of about 1500 feet, the emissions control light comes on. It goes away after refueling but will come on again after about 60 miles. The engine is also a bit hesitant at times on the interstate. I replaced the gas cap yesterday so we'll see if that fixes it.

I changed out the spark plugs. The four on the driver side were covered in white and had about a .07 gap. The four on the passenger side appeared to be lightly used and had a .05-.06 gap. Almost as if the dealer changed out the passenger side last year, when I bought the truck, but not the driver side. Replacing the spark plugs hasn't fixed the emission light or hesitation issue. Although it appears the truck has a lot more get-up-and-go.

My other big issue right now is that when I attempt to pull codes, the code reader says it cannot connect. So I'm getting no feed back on that and cannot figure out why.

Frustrating.

 

My $200 code reader couldn't pull the codes but the $50 pocket scanner can. Consistently reading EGR valve high limit and flow errors.

Yesterday it starting throwing around a TPS code. I'm going to replace both the EGR valve and the TPS this weekend. Working with my dealer to see if they can get it covered.

 

sounds like an 02 sensor to me, also the white on the plugs might mean the head gasket is going

 

The O2 sensor is next up to be replaced if the issues continue. Thank you for the idea. I replaced the TPS tonite and so far everything seems to be fine. I no longer have any engine codes or CEL.


Service manual is way off on the location of the EGR valve. I'm going to wait to see if that code comes back before replacing it.

 

might be the EGR... i did mine at 90k and it made a big difference. its a little bit of a pain to get at too. well one bolt is in a bad spot, and dont drop it! it will be forever lost!!! my symptom was very poor gas milage! dont know if your experiencing that too?

 

I was at 11-12 within the city and am currently around 14-17 after changing the plugs. I saw the location of the EGR valve and nearly cried. I'll attempt replacing it this weekend I guess. Lucky you got 90k miles out of yours. I'm at 50k .

 

it will fix your problem..... good luck! and be carfull!