2005 rough idle, codes, P0131 P0171 P0300

[j cAT]

Originally Posted by kahjdh

I dont know if anybody else has experienced this but we had alot of 5.3's come into the shop w/ bad intake gaskets and we threw a new set on them. After about 6months they come back with the same problem and when we smoke test them it is the same ports leaking. These plastic intakes are like the 3.8L and warp causing leaks.
If this problem coms back Dorman sells whle intake kits which we replace everytime now to prevent comebacks and pissed off customers. Just my 2 cents.

he only had a bad pcv vent hose that caused this not a gasket issue..............

[87racer]

ok, i wonder if this is similar to my problem. i get a 0300.171 and 174. truck runs rough and smokes black i sprayed everything with carb spray and no luck with a change of idle.... any ideas?? thanks

[jyount]

Fuel pressure? I have also seen the same result with dirty injectors. Bad thing is its is nearly impossible to clean em out if they are clogged. The walmart stuff is junk, doesn't work when you have problems....

[weo38]

I am having the same issue with my truck(05 Silvy 5.3). The only code i get though is the one for the O2 sensor. My problem is not consistent though. Sometimes it does it and sometimes not. Temperature does not seem to affect it. Very frustrating when it is not a simple diagnosis. Any ideas would be appreciated. I am going to try the carb cleaner trick this weekend.

[87racer]

actually, intake was warped. sucking air. changed it to a dorman(nice piece) . still missing some . going after a few injectors as i did a test and 2 of them didnt drop as much. hope this works. i am sick of this thing!! thanks for everyones help. do ya think this is a step in the right direction??

[kahjdh]

They do warp all of the time.
If you have a bad injector post back to tell us if the top is clogged or not.

[weo38]

Did the same as 87racer. Sprayed everything with no change. Seems to be intermittent, not consistent. I wish the codes weren't so vague, so us shadetree mechanics can fix our own stuff. Let us know if it is an injector and how to test.

[kahjdh]

Injector test, you can do a drop if you have a scanner or just go one by one and unplug them and see if the engine idles differently.

[j cAT]

Originally Posted by weo38

Did the same as 87racer. Sprayed everything with no change. Seems to be intermittent, not consistent. I wish the codes weren't so vague, so us shadetree mechanics can fix our own stuff. Let us know if it is an injector and how to test.

what DTC did you pull...?

[weo38]

0300,0171,and 0131. I replaced the o2 sensor last night so I will see if the light stays off now. Truck goes in for inspection on Monday, if the light is on then they will tell me and fix it. Keeping fingers crossed though.

[87racer]

ok, the truck is finally good to go!! I changed the intake, dorman one is nice. changed one questionable injector and both s1 o2 sensors were fried. thanks for the help!!

[weo38]

Mine turned out to be just the O2 sensor on bank one. Runs good now. Glad O2 sensor was only 40 bucks.

[suburban3]

I had the same codes on my '05 5.3 L. It was in fact the O2 sensor. Bank 1 Sensor 1 is the driver front sensor.

[crs246]

I have a 2005 Z71 5.3. Mine had rough idle after warmed up. Ran good at speeds......

It had codes p0131, p0171, and p0300.... I had to change the O2 sensor on the drivers side just beneath the manifold. The Check Engine light cleared on its own two days later...


All good now. I like to fix things myself. It was good to read everyones comments. I joined hoping to help people like me. Keep up the great work everyone...