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ok guys new here so this may be the wrong section. but here goes my issues. i doing this repair for a disabled vet that lives across the st. 

first is a p0300 that i just can't nail down. the odo has 308,000 miles on it but i do not know if the cluster is original or the engine rebuilt.  so far items installed by his boy are new TB, maf, and  map. i just did the plugs  it has 18" vacuum  64# fuel pressure 40# holding  185 to 200# compression  i found 1 broken wire around the trans lines and antilock brake unit and 2 well scored so i cut them and but connected them that was a trip. then i found a scored wire located below the egr going up and over the head i could not do much so i wrapped it in wire loom. it was just worn insulation there.  the engine seems to run fair at speed with a now and then stumble but at stops it misfires often and then out of the blue while idling at 700 ish it just stops, like you turn the key off. i also tried turning the key slow from almost off to full crank to see if by chance it may have a bad igh switch, nothing odd happened.

in the live data it shows tons of misfires on most cylinders. the coils and injectors are still original i did not swap out the coils because of the random misfires being all over the engine.

 the old plugs were almost white i can post tons of live data freeze frames and photos if anyone want to tackle this online.  also it has a bad oil leak somewhere around the front passenger side tire in front of the tire a bit. i have not checked this out yet but the owner claims it is the engine oil cooler housing to the block. but i just can't fined any video or reference to that online. 


if anyone want to view all the live data here is a drop box link. they are in order from before the compression test to after

this is live data from after the TB maf  map  plugs and the 3 wires patched


this is after the comp test and the las wire patch



but the main question is what might be leaking oil in the front passenger side of the engine radiator area. i have not looked at it yet and do not see any online repairs for that area and engine oil cooler as he says it is. and want to get a handle on possible repairs before i volunteer to fix this one. i though random misfires would be easy and it is kicking my *smurf*  

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Oil leak will need examination; there are oil and transmission coolers.

Misfire:  I would still suggest coils -- there are two coils for 8 cylinders.  One may have gone intermittent, and then the other at this point especially if original equipment at 300K miles.  Also, coils are a regular maintenance item (do fail).


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not the transmission lines i was in that area repairing the wires and the lines are dry at the transmission and along there length to the cooler.  and this engine has 8 coils it is impossible for all of them to be sending out misfires. i can see 1 or 2 maybe 3 but not all 8.   but i did find a Yt just now that shows the oil filter that has the oil cooler ports and that seems to be a common point of oil leaks on this engine. so i'm going to go with that and then if i find the hoses leaning deal with that another time. thanks

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so looks like no one has dealt with this before. i tried pulling the cam sensor today and that did not help. out side of just taking the engine all apart i have no idea where to look anymore. also it has a bad oil leak in the area of the oil filter. it looks like the housing to the block has failed. seems to be a common issue. but i tried to take the thing off today and i just can't get the bolt out at the top right of the housing. outside of dismantling the motor mount and taking half the body off the front to gain access. i did se a YT showing how to do that but they did not have the cooler lines running out of the housing. so can anyone point me to the oil cooler delete parts? or maybe just cut the lines and get an ebay housing without the oil cooler and just install that? 


but that p0300 is driving me nuts. if trying it without the cam sensor on it and i still get the misfire then about the only thing left that i can think of is the crank sensor and that is work to get to also. but you would think that after 9 years of driving this car that, that sensor would have failed by now. so tell me outside of just getting every sensor and installing them can i get a junkyard computer and install that without having to get it programmed?

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