Hey guys I need some help.

I have CEL code P0170 being thrown on my 2001 Evo 7. I assume that this code is the JDM equivilant to P0171: lean. Is that correct?

The funny thing is that when cleared it stays off during normal driving. Then when out on the highway, after about 20 minutes at 80mph it will pop right back on. This last time that i pulled it, the scanner said it happened at 78mph under 25% engine load. I cleaned my mass air once should i do it again? what else could it be????

I really need it taken care of so any ideas would be helpful!

Thank you,

Tim Jordan

PS i have searched the topic

 

bumpity

 

any ideas guys?

 

Trims are off.

Aftermarket Injectors?
Boost/Vacuum Leak?

 

stock injectors... i read up on the dsm board where this p0170 is a fuel trim malfunction said maybe dirty fuel filter or bad front o2

does that sound possible?

 

bump

 

just remembered something, i messed with the idle adjustment screw on the back of the throttle body, could this be apart of the problem?
how do i readjust it correctly?

 

take short screw driver (philips IIRC)
tighten (or loosen) it one turn, let car idle for 5-10 mins for ECU to learn, drive it around and see if code pops up again. If it does, repeat process. Having to deal with similar issue right now since having aftermarket TB/injectors installed... still getting 171 code but less low-idle dips, it may still take boost leak test and checking injectors/fuel filter etc. to rule out cause of CEL