o2 codes and maf codes oh my

ant0045 · Nov 25, 2009

last couple days my car has been running like shit. When i first start it up it runs like complete crap. If i tap the throttle it will die but if i give it alot of gas it will stay runnning and run smooth. It also is running very rich at idle and barely wants to idle. When it is running bad if i try to mash the gas it will take forever to rev then it will take off like it has vtech. At times it will also run like nothing is wrong. Today i pulled the codes and got code 159 for the engine running test and got 157 158 177 for the memory codes. The voltage on the o2 sensors switch from 50-1000mV which is within spec but the one got stuck at 87mV and then continued to keep working but alo continued to stop switching. I checked the voltage on the MAF and at idle it was at like .23 volts and when i revved it up it only when up to .33 volts. The inputs on the MAF have 12v and 5v. What is everyones input on this. Im going to put new o2 sensors in tonight or tommorow morning. I searched this forum and alot of people same to be experiecing the same problems i have but none of them ever finish a post or post how they fixed there car if they ever did. So hopefully i can finish this thread to help some people out, including myself.

GDTrumbo · Nov 25, 2009

That acts like my wifes '08 Escape when the MAF sensor went down.......

GT

95GtStang420 · Nov 25, 2009

if u have problems with he car idleing and boggs out on you more then likely bad mass air flow, try cleaning it..if you o2's are going as far as 87mv they are still working good just alittle lazy,

ant0045 · Nov 25, 2009

yea i threw a code for slow switching and that vtech feeling which from what i gathered online so far is from the o2's. i ordered the maf and o2's they will be here on friday.

GREG@SN95 · Nov 25, 2009

159 for the engine running test and got 157 158 177

157 - MAF sensor went below 0.4 volts during the last 80 warm-up cycles
158 - MAF sensor went above 4.5 volts during the last 80 warm-up cycles
159 - MAF signal was greater than 0.70 volt during KOEO (O), MAF signal was not between 0.20 and 1.50 volts during KOER (R)
177 - o2 Sensor circuit indicates system rich (left side)