Hello, I did some searching, but didn't really find what i was looking for.

I picked up a 1999 DII knowing it was throwing codes. Temp sensor, MAF, and O2 sensor were the first ones. Replaced all of those, and all was well. I drove it around town today. All good. Until... I did a 20 miles interstate run at about 70mph, came off exit ramp and bad shudder while at stand still. Give it gas, smooths out. SES light didn't come on (but was on previously).

I plugged up the scanner and now have:

P0130, o2 circuit , bank 1(they were all just replaced)
P0300 random misfire
P0303 Cyl 3 misfire
P305 Cyl 5 Misfire
P0101 System too lean, bank 1
P1171 System too lean bank a and bank b

What in the world?? Something must be off, what do i check now? I don't see anything leaking around those cylinders (at least on the outside). I hadn't pulled the plugs yet, but wondering what else could be causing this.PO replaced the plugs and wires, that's all new. It seems to run better when its cold. The original issue was rough idle when cold. Once the Temp sensor was replaced, that issues went away, now it runs bad after warm at idle in gear.

 

pull the plugs and check the wires on number 3&5, they are on the same coil pac.

on you o2 sensors disconnect then clean the connection and apply some dielectric grease, see if that helps.
also what brand o2's did you install?

 

All Bosch. PO said Wires are NKG, not sure on the coils but he did those also when he did the wires. Would make sense now on the coil for 3 and 5.

 

i would start pulling the 3 & 5 plugs and see what they look like,
fouled, wet, carbon.
i would them swap the #3 & #5 wires and see if the miss fire follows,
if it follows, you have bad wires.

I too replace all my o2 with bosh and had trouble until i cleaned everything up,
you see any leaking engine oil like to run down the cable inside the connectors.

your scanner must tell you live imformation, what kind of reading are you getting on the o2 sensors?

any coolant leaks that you know of?

I would rule out everything before springing for a coil.

 

No coolant/oil leak .45 (so illegal value) on all of them except one, .59. I need to grab it when its warm and does it again to get actuals i guess. Ill pull the plugs and clean and grease the connectors and see what happens.