Thanks in advance for any help diagnosing this problem, long time lurker to this group and have had tons of good advice in repair of my stable. I did read historical posts for several days now and cannot find the problem with what I have been reading.
My 740 suddenly started to smoke badly from one drive early in one day to starting it that evening. Its a weird smoke, in that it seems to roll out not really related to engine speed. In fact when first started, there was no smoke and then a few seconds later it sort of rolled out at idle. It doesnt seem like an air mass sensor, because [my 82 would not start with a bad one unless placed in limp] that smoke was ?thinner? but always smelled rich. This smoke smells like bitter diesel, and isnt blue or black, but white [no coolant loss that I can tell] Here is what I know: bosch lh jetronic 2.4 system battery was slightly low on volts 12.2 [charged now] oil was weird, thin , not milky replaced it and filter Pulled harness off AMS and slightly corroded, cleaned, replaced = smoke Pulled the air cleaner and found that a piece of deteriorated foam from the cover was blocking 1/3 of the intake of the AMS. removed all foam, replaced =smoke pulled oxogen sensor connector, slightly corroded terminals/wires, cleaned, replaced=smoke pulled each FI wireset, no corrosion, replaced=smoke pulled fuel pressure reg vacume line, no fuel in line, replaced=smoke pulled/checked flame trap hoses, not clogged at all, replaced=smoke pulled other vacuum lines and checked all i could reach/see, no missing/unhooked/holes,,. still smokin slightly corroded ground straps to firewall from valve cover,, only surface corrosion not at lugs, replaced=smoke pulled outlet to intercoller line from turbo, not too dirty. pulled intake to turbo, not too dirty, turbo spinns freely, no play/wobble tested AMS [kinda] did not know [ala chiltons manual] which was the signal ground of the bl/g bl/r bl/w wires.. Ignition=on, connector =on: had 12v on bl/y and br =grnd other wires to ground varied among millivolts, but definetly had a reading on all, none in the .1 volt range all lower did not test ox sensor, afraid to warm up engine [only run for movement of car since that evening and testing...] dont wanna blow the cat. or ??
Error codes pin 2 test "1" got a 1-2-1 =AMS absent/faulty [rember the foam chunk?] did not reset to recheck got 3-1-2 no knock enrichment from "DI system" [what is DI system?] got 2-3-1 adaptave fuel mix too lean or rich then pin 6 test "1" got [forgot code] EGR temp or flow error
I have read posts about Y shaped vapor lines near the turbo/under the turbo.. all I have are oil and coolant lines the turbo is mitsu because the ss band in the middle [right?] I have not checked the oil lines to the turbo [chicken for now] I have not checked the sp plugs [REALLY] tight/hard to turn out, afraid to strip and create more problems...got plenty now I have not checked the knock sensor [again chicken for now to pull off the intake] I have not checked the injectors for spray pattern [not a gradual smoke, a sudden smoke]
I dont want to go replacing the turbo or AMS as tests..but do not know where to go next.. Any ideas?
Thanks Dave Simon
92 740 turbo wagon 150k 82 240 dl 250k