bank 1 lean and random muiltiple misfires... WHY!? egr? upper intake gasket? TB gasket? where to start? i have a crate motor with less than 7,000 miles on it.. so i know there is nothing wrong internally.... injectors/ poppet valves were just checked. new fuel pump is new and so is regulator... where do i start? im soo lost this time...

 

Check the DIY section for the trouble code diagnostic information. If the diagnostic for P0171 does not result in a fix, run a search for P0300. There was a thread that went through pretty much everything concerning the random multiple misfire code.

If you have an exhaust leak on bank 1 (driver side), it can cause both of these codes to set.

 

i read the p0300 DIY and didnt really help.. its running lean? i just changed the o2 after the cat so im lost.. i geuss im gonna change all upper intake gaskets egr gasket and see where that leaves me.. i just cleaned my MAF i wonder if some how it was just damaged before i cleaned it or even when i cleaned it... im lost? i had it run rich and it was the ignition control module so now im lost?! im ver hands on and always try to fix a problem myself first so im gonna check over again and see what is going on...

 

What are you lacking as far as the DTC diagnostic charts are concerned? Were you able to walk through the chart?

I would concentrate on the P0171 code first anyway. And the post cat O2 sensor has absolutely nothing to do with engine operation. It is an emissions monitoring device only.

If you want to just throw parts and money at it, be my guest.

 

so what are you suggesting? i habe a pocket scan so no i seen no chart

 

The diagnostic chart is in the DIY posts I have made about these codes. Follow through as much as you can. And that pocket scanner of yours is really a waste. Saves you from having to go to Autozone or Advance I suppose, but it cannot access anything but P0 codes.

Now, if you have specific questions from the P0171 Explained post, ask away, but I cannot walk you through every aspect of the diagnosis. You have to do the work and let us know the outcome.

 

well after checking for whistles from vaccum leaks and found nothing i decided to check the EGR to see if it was stuck.... heres what i found

http://img213.imageshack.us/my.php?i...mg00116qo3.jpg
http://img213.imageshack.us/my.php?i...mg00120cz3.jpg
http://img117.imageshack.us/my.php?i...mg00124sv8.jpg
http://img117.imageshack.us/my.php?i...mg00123cg7.jpg

should the egr valve be easy to push in? and when i did black soot came out? so i took a putty knife to the egr valve base and the intake base.. should my in take look like its covered in valvet? it is a brand new crate long block? form jasper motors..

 

Looks like you may have a faulty EGR valve. I have one I just pulled from a 1996 Astro van that I know was working when pulled. I was going to keep it for reference when members have questions. I will see how difficult it is to push in on the pintle. From what I can remember, it should move with some resistance.

 

mine has very little restance... but moves smoothly... the gasket looks blown... it was recently in the shop when it was running rich and they checked the egr valve... i wonder if they were to cheap to replace the gasket when they checked it over? ill go to autozone and see what a new one feels like....

 

my egr valve pasted the test so i cleaned it up.. we'll see if that helps