HELP po300 and po175

[DrSheldonCooper]

i wouldn't worry about the plugs or coils to start, because if it's a random misfire, it's something that's messing with random cylinders.

i would most definitely check ALL rubber hoses and inspect them for small cracks and what not. when it's cold things will shrink, so those hoses will get small and will leak. then when they get warmed up, a small tiny leak could get covered up just by the hose expanding due to the heat. a vacuum leak will most certainly cause a random misfire.

[DrSheldonCooper]

i'm thinking of a MAF sensor, but these jeeps use a MAP sensor to calculate load n what not.

i'm all over the place tonight. sorry for the wrong info.

[svoteam]

Originally Posted by AROD

Do you have an A/F Guage ?

Sounds like you are running lean on cold start up...

For what its worth, p0300 means its a random misfire.. if it was cyl. specific it would end with a 1-6

yeah i have a wideband im running agout 14.5 to 14.8 at idle when this is happening

[svoteam]

Originally Posted by Knuckles

Mine did something similar and I got a P0174 and it happened when I installed my 90 mm... It went away after my tuner adjusted the tune.... Have you done any work on the Rig lately? Also our rigs don't have a MAF sensor......

i emailed jersyboy with my log lets see if he sees anything

[svoteam]

Originally Posted by DrSheldonCooper

i wouldn't worry about the plugs or coils to start, because if it's a random misfire, it's something that's messing with random cylinders.

i would most definitely check ALL rubber hoses and inspect them for small cracks and what not. when it's cold things will shrink, so those hoses will get small and will leak. then when they get warmed up, a small tiny leak could get covered up just by the hose expanding due to the heat. a vacuum leak will most certainly cause a random misfire.

thanks dan, i will check out my hoses this weekend,
walt

[JerseyBoy@Stage6]

Originally Posted by svoteam

i emailed jersyboy with my log lets see if he sees anything

How about you check your email. I sent you a cal to try last night ;-)

J

[svoteam]

Originally Posted by JerseyBoy@Stage6

How about you check your email. I sent you a cal to try last night ;-)

J

lmao thanks j, just did, will try it out and let you know
walt

[svoteam]

ok here we go, just installed a cold weather rev from jerseyboy and all looks good, not that cold today but i had no problems startup and warmed up like it was supposed to,
thanks J
walt

[AROD]

Glad to hear it worked out for you! - but keep an eye on the underlying issue. There has to be a reason why ( on cold starts ) you get the CEL.

[JerseyBoy@Stage6]

No issue to worry about. The cold start fuel was just a little lean causing misfire on cold start when the temps dropped. She's good to go now ;-)

J