Help!!! My Check Engine Light Is On!!!

[littlewing2]

Hi. I went to Auto Zone and they ran it on their scanner. The codes are P0171 and P0303. Could someone tell me what they mean? What needs to be changed out? Your help is greatly appreciated. Thanks, Nancy

[etlsport]

p0171 is "system too lean (bank 1)" from what ive read it looks lilke its usually caused by a bad intake manifold gasket.. which is common on our engines

p0303 is a cylinder 3 misfire, could be spark plug, maybe intake manifold gasket? not sure someone else can chime in on this stuff

[johnnyapollo]

They both could be caused by the bad gasket. The original spec had the torque value too high - over time the phenolic fails. I don't remember the new value - something like 9 lbs (original was double that). It's not an expensive fix if that's what it is, provided you can do it yourself (part's aren't too bad).

-- John

[etlsport]

i think the new value is 13ft-lbs and the original was like 17-19

[ScottinMA]

Can't recall the codes but my check engine light came on recently and one of the values pertained to the engine running lean. I also noted that it would stall out easily at low RPMs. Turned out to be a missing screw from the EGR that resulted in a vacuum leak. Replaced screw and Check Engine light went out as did the stalling problem.

[littlewing2]

If I have to replace the intake manifold gasket, am I better off getting it from Isuzu or AutoZone or Napa? Or are they all the same? Spec torque? Thanks again, Nancy

[Ldub]

If I have to replace the intake manifold gasket, am I better off getting it from Isuzu or AutoZone or Napa? Or are they all the same? Spec torque? Thanks again, Nancy

Whenever replacing a part that you have to "dig" for, meaning removal of all sorts of other stuff, before you actually get to the part in question, such as timing belt, water pump, thermostat, intake gaskets, etc., I usually choose OEM Isuzu.

There was just a post a bit ago, lamenting the fact that the brand new autozone water pump that had just been installed leaked from day one.

For speedy service, good prices & free shipping, search Merlin @ St Charles Isuzu.

jU$T MY $.02