P0300, P0302 and P0171 Help

[maddss]

99 Limited with 260k.

Got the dreaded P0300 & P0302 CEL code 2 days ago. On first start up, (cold) there is no misfire. Only starts after the truck is warm and 2-3 starts. This is what I have done with NO success.

Replaced the Coil (new one), changed out the wires (all) and changed the #2 plug and still have the CEL. Also completed a compression test of the #2 cylinder of 170psi same as the #4 cylinder. All fuel injectors taken out, cleaned and flow checked, all good. #2 injector connector noid test was good


Checked the MAF, for resistance this morning. 1.7kΩ which is out of range, 2.2-2.7, next step is to replace it. Cleaned the MAF and P0171 is now gone.

What I'm missing, any help would be great.

 

[maddss]

Anyone

 

[cl4Rk]

P0171 is no gone.

I’ll be watching to see what others say about the misfire codes.

I can only speak to my experience with the P0171 code, which for me was caused by a couple pretty small and hard-to-find vacuum leaks. I did the “spray and listen” test and replaced several hoses.

 

[gamefreakgc]

If the MAF is off, everything is off. Can't really go much further in helping if you know you have a bad one. DENSO only, junkyard units work ok if money is an issue. I got mine off a V6 Camry, though yours is a 99 so different style.