Very Rough Idle/Missing - Basically No Runability

this has been a very long battle so ill try to summarize this as well and

as short as i can first off the problem

i bought this 95 runner (v6 automatic) my 5th one....guy couldnt get it

started (no spark) he tried some things and gave up and i bought

it.....tested alot of things....ended up findin that the motor had

overheated ALOT and the egr hose had broke and burned the engine harness

(melting the distrib wires alot with others all together and therefore had

no spark)

fixed the harness and when the fire up the motor.....ran like hell

did compression check had 180 psi in 2 cyls...and 0 in all others....

pulled heads....found ALOT of burnt valves.....got a new set of heads off

a 90 3vze motor

put it all back together now have 175 psi to 180 psi in all cylinders

yet still runs like hell....starts but when it idles its very very rough

almost like its out of time...and when you throttle up it more or less

gets worse and black smoke comes out exhaust and the pinging begins....

its sounds like a fuel or timing issue but i am pretty sure i have covered

everything....it might be somethin im missin so i hope this post will give

me some new motivation....

here is the list of things that have been tested or replaced

valve clearance
head gaskets
all upper end gaskets
fuel filter
fuel pressure regulator
injectors
distrib (cap and rotor)
coil
ignitor
ecu
tps
maf
plugs and wires
vacuum lines

i have check timing a dozen times and to be honest im sick of takin it

apart. haha....i know the timing marks are 100% on....

i guess the only thing im not too sure on....is if there is any difference

in the 95 3vze to the 90 3vze motor....i compared cams and all and they

look the same....i know the obd1 motor will have more sensors like the egr

sensor and what not....but mechanically is there a difference...maybe like

the distributor teeth on the cam are different or somethin so my distrib

isnt firing right....i dont really know where to go from here....im a lil

at a loss....i am pretty damn good with vehicles and my neigher is a

diesel mechanic and my roomate is a nissan mechanic and we are all

stumped....

any ideas??

Have you checked all the vacuum diaphragms for leaks?

I'm just throwing this out there but I'm pretty sure you have to jump some wires on the Computer to set the timing (i don't have a V6 so only repeating what I've read).

Maybe you overlooked this?

You can also get a readout of engine error codes I believe by jumping some wires as well. Maybe some of the other guys can chime in with details.

Did not mention checking out the EGR system. If it is sticking open or is mis-plumbed and staying on, that can cause a rough idle and poor running.

sorry forgot to add that.....egr system been checked and it is functioning correctly....

as far as the jumper to check codes....im not throwin any codes.....so that wont help much =\

and i cannot even get a solid reading on the timing cause the motor is jumpin all around....so jumpering it and trying to put it at -10 is pretty much a crap shoot

thanks for the replies tho =]

went out this mornin thinkin it fixed itself over night....and it didnt....

hahah....anymore ideas?

no leaks...but there is the one diaphragm that connects to the right bank's manifold and one large hose connects to it....not sure what it is....or what is does....but last time i had one of those fail it was really loud...and didnt mess with motor performance....