EGR issues!! HELP

[Brandon8965]

this code P0400 keeps popping up no matter what we do to fix it. it says "the ecm had detected too little flow on the egr system"

what can i do to fix this with out replacing the egr valve itself...

i guess i will if it comes down to that though.

[allensteiner]

the valve might just be dirty as hell - take it off and you'll see. carbon builds up inside and over time restricts the flow.

[Brandon8965]

is there a trick to gettin it off that i just don't know about?we tried for a while and stopped due to lack of sunlight

[allensteiner]

idk, i'll take mine off for the first time when i get to my valve cover gaskets. i would assume that it's a pain to get it off with the intake manifold on...but i've got fat hands too and had issues replacing the fuel filter.

do you need the fsm link?

[Brandon8965]

yea that would help.. ha my hands are huge too, tha knock sensor was.. well you know

[allensteiner]

http://www.nicoclub.com/FSM/maxima/1999

here you go. and yeah, i always curse those damn japs with their tiny hands

[Brandon8965]

thanks man

ha yea i had to get an asian friend to ultimately put tha new one in... my hands were too bloody

[allensteiner]

was it just plugged up with carbon?

[Brandon8965]

o man i was talkin bout tha ks... still haven't touched tha egr... gotta change oil and go to work lol

[Q45tech]

Everything must be clean as new including egr plenum passages, all the way to eshaust manifold connection. Homemade tiny roto router from a accelerator cable on a drill.

[NutriaforBreakfast]

On my 1995 you have to remove the air filter plumbing to get tothe EGR valve. Start you engine and have a friend rev it up andfeel (better put gloves on) to see if the diaphram is moving onthe EGR valve. If not maybe you can carefully move it ascarbon might be possibly stopping it. It probably could use somelubrication so use some brake cleaner. If it doesnt move, you mayneed to replace it if the other EGR components are ok.

Since my car had 161K on it, I replaced it. You will need a large longwrench, about 1 1/8" (Approx). It was difficult to replace it so giveyourself plenty of time and get a friend to help you.

When I changed my valve cover gaskets the EGR tube connectedto the plenum (upper intake) was constricted by about 75% so Icleaned out the carbon there (I like that idea to pig out the linewith a drill and brush).

You might have a blown EGR gasket (probably not-the one bythe EGR valve and the EGR tube one are both metal)

You also have an EGR actuator and another EGR component (cant remember) but they are in the shop manual and they might be bad (electrical maybe)

I hate that EGR tube. Why couldnt you reroute that thing from theback of the plenum and t it into the PVC valve.?

[Brandon8965]

yea someone told me bypassing it would screw up the engine completely

but yea i can't get any of the hoses off of tha thing cause my hands are too big lol

[drg007]

check ur egr valve if the selenoid is doing is job and clean all the carbon build up inside the passage