Been a while since I posted, My car set for 2 -3 years with bad motor harness(squirrles) which I finally replaced. drove for couple weeks then wheel front bearings making noise so set again for a month to replace bearings and axles. I have been driving for 2 months now without any problems until a trip to Nashville. On the way home CEL came on. checked when home with cheap reader and had P1174 and one other that I can't remeber. I cleared code as car seems to be running fine but code comes back on the second run cycle evertime. I borrowed a scanner to get a btter look.. This has been going on for week now but car seems to be running fine, If someone could point to a starting point I would appreciate it.

Current codes

P1174, Fuel trim cylinder balance ONLY CURRENT ERROR


Freeze Frame Data

Loop status closed
eng load 33%
ECT sensor 87 C
short term fuel trim banl 1 -1 %
long term fuel trim bank 1 5 %
map sensor 48 kpa
eng speed 1792 rpm
vehicle speed sensor 79 lm/h
spark 38 deg
IAT 34 c
Mass air flow sensor 10.24 g/s
throttle position sensor 1 28 %
HO2S bank 1 sensor 1 755 mv
HO2S bank 1 sensor 2 770 mv
eng run time 4:16
evap purge sol command 43 %
fuel level remain 83 %
warms ups since DTC cleared 2
calibrated TWC temp 702 c
command air/fuel equivalence ratio 1:0 :1
throttle position sensor 1 indicated position 17 %
ambient air temp 31 c
throttle position sensor 2 28 %
APP sensor 1 25 %
APP sensoe 2 12 %
throttle position desired angle 22 %
ignition 1 signal 12.54 v

 

Most if them are voltage related. Sitting for years give rodents a chance to sample soy based wire insulation. Make sure the 4 bolts inside the underhood fuse box are tighter than you think they should be; back them off then tighten from the center outward until King Kong can't turn anymore. Check the wire connections at the large red wire on the outside of the fuse box. Check that all fuses and relays in both fuse boxes are seated. Look for any wires laying on hot surfaces or frayed. Don't go back to Nashville.

 

Sorry, I apparently looked at the data wrong when I printed it, The only current error is the P1174 and yes I had no stop errors for several cycles when I put power back to it. I have updated the original post.

 

You could be lucky and have a bad wire or #1 O2 sensor. Did you replace the #1 o2 sensor? Cheap ones suck, NTK/NGK are good.
Could be a cracked flex pipe or other leak before the #1 O2 sensor. Could be bad injectors. Could be a bad MAP. Could be bad wires. Could be Nashville.

 

Only thing I have done since codes is to replace the plugs. I'm just trying to make since of the readings as I am a industrial tech not automotive.tech. It seems the readings are within the ranges I have access to but maybe a little toward the rich side. Is there something else I can look at with the scanner that may help narrow the field.

 

What spark plugs did you install?
AC Delco 41-103 iridium are the only ones the engine is designed for.
torque to just 15 foot pounds

clean the MAF sensor with sensor safe spray you may also have dirty fuel injectors, perhaps a Seafoam treatment

 

The shotgun approach is to replace the upstream O2 sensor(s). This resolves a bit better than half these issues.

 

Well, looking at the plugs you listed I'm going to say they sold me the wrong ones and I didn't look close enough. Will check as soon as possible. Got a chance to check for exhaust and vacuum leaks and the only thing I found was an oil leak that has now side lined the P1174 repair. Something is leaking pretty good around the area of the filter or just under. Also looks like the top trans cooler line at radiator is starting to leak. When it rans it pours.

 

That oil leak is probably the oil pressure sending unit

 

My 1st guess would be when it sat the injectors gummed up and now the ECM can't find a trim that works because all the injectors are flowing at different rates.