please help, my ls is going nuts!!!
#47
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i replaced the afm/maf with the same part number, tried 2 different units.
the timing question- yes ive checked and double checked the mechanical timing, ive had it at tdc 2-3 times and it stays true. besides, it wouldnt run perfect on new starts (battery disconnected, ect.) for 5-10 minutes before falling back into this mode.
i replaced both CAS, and no effect. still persist. however, the left harness that goes from the CAS to the main harness, has already been repaired once, and i thoroughly checked it while i was doing the driver CAS.
tomorrow ill tackle the crank sensor.....though i feel its not it.
its burned 1/2 tank of fuel sitting in the driveway trouble shooting, and like stated before the injectors get loud when it goes into its problematic state, does the crank sensor have any effect on the injector pulse in the 1uz?
also ive been finding that the driver side bank harness is known for broke wires, and ill connections. this would make sense that when i unplugged everything and plugged it back in on that bank, without disconnecting the battery, the car ran right for a few minutes, before falling back into its current state. so ill also be going over that tomorrow.
a few questions though:
1. where is the main harness ground on the engine?
2. how do these vehicles react to old, or low life batteries? im asking because of the light dimming situation. im getting 14.7 volts at 1500rpm revs, so the alt is doing its job, but when the car is off, im getting 12.3-12.5 volts from the battery. this battery looks fairly new, but you never know. the light dimming issue raises an eyebrow here.
3. ive also read one instance before where the oem amp causes a mass of issues, where it shorts out or creates an ill upset in the electrical system. one guy even reported a weak spark, poor idling, and not rev happy, unplugged the amp, it was scorching hot, and the issues went away.....ever heard of this issue before? common? it has an aftermarket head unit in it, but the installer used the aux ports out of the rear of the radio to run the channels into the oem amp vs. using the grn, prp, gry, wht speaker wires.......
the timing question- yes ive checked and double checked the mechanical timing, ive had it at tdc 2-3 times and it stays true. besides, it wouldnt run perfect on new starts (battery disconnected, ect.) for 5-10 minutes before falling back into this mode.
i replaced both CAS, and no effect. still persist. however, the left harness that goes from the CAS to the main harness, has already been repaired once, and i thoroughly checked it while i was doing the driver CAS.
tomorrow ill tackle the crank sensor.....though i feel its not it.
its burned 1/2 tank of fuel sitting in the driveway trouble shooting, and like stated before the injectors get loud when it goes into its problematic state, does the crank sensor have any effect on the injector pulse in the 1uz?
also ive been finding that the driver side bank harness is known for broke wires, and ill connections. this would make sense that when i unplugged everything and plugged it back in on that bank, without disconnecting the battery, the car ran right for a few minutes, before falling back into its current state. so ill also be going over that tomorrow.
a few questions though:
1. where is the main harness ground on the engine?
2. how do these vehicles react to old, or low life batteries? im asking because of the light dimming situation. im getting 14.7 volts at 1500rpm revs, so the alt is doing its job, but when the car is off, im getting 12.3-12.5 volts from the battery. this battery looks fairly new, but you never know. the light dimming issue raises an eyebrow here.
3. ive also read one instance before where the oem amp causes a mass of issues, where it shorts out or creates an ill upset in the electrical system. one guy even reported a weak spark, poor idling, and not rev happy, unplugged the amp, it was scorching hot, and the issues went away.....ever heard of this issue before? common? it has an aftermarket head unit in it, but the installer used the aux ports out of the rear of the radio to run the channels into the oem amp vs. using the grn, prp, gry, wht speaker wires.......
#49
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How about the fuel pump control box? Not sure if thats the proper name for it. Its mounted on the passenger wheel well below the AFM and some sort of relay block.
Just takin a stab here. Can any one remember the name of this part? I dont have access to my FSM right now.
Just takin a stab here. Can any one remember the name of this part? I dont have access to my FSM right now.
#50
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Wow man, you handle this well!
Maybe what you can try and do is track the fuel lines, look for leaks, and if you can somehow get a sample of the gasoline at the bottom of the tank, see if it is nasty yellow. Maybe you need to pump the tank to get all of the debris and crap out. Code wouldn't be happening if that was the case though...
What parts have you NOT replaced? IACV? Coils? ECU?<== you did replace that, right?
Cheers
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What parts have you NOT replaced? IACV? Coils? ECU?<== you did replace that, right?
Cheers
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crank angle sensor changed......same effects, however:
its trying to clear up. i also have about 5-6 fuse boxes lying around from other toyota swaps, so i decided to swap out some relays, just as a stab in the dark, its trying to come around, better than it was by far. i was able to do a full throttle sprint down the road up to about 80, (guessing, because the speedo still isnt working). i also pulled the no.1 radio fuse out from under the hood, but my head unit is still on......? im guessing the fuse is for the amp? same thing though, shut it off, started it back up, and it idles at 1500 with barely/poor acceleration.
also when i disconnected the old crank angle sensor, i found that the connector was slap full of oil. cleaned out the connector needless to say.
shot in the dark? whats the trans sensors consist of in these cars? are they heavily linked into the ecu, meaning that if a speed sensor goes out, etc., would it cause wierd issues?
also found that the last plug, closest to the firewall on the drivers bank, that little seal that goes around the plug wire insert tube, is pushed all the way in......hmmmm, severe vacuum leak? waiting for the engine to cool now, ill be pulling the valve cover off, retrieving that seal and putting it back in the way its suposed to be, im hoping that, its allowing enough air into that whole that, its directly pulling through the pcv, and its creating a high idle, and also allowing unmetered air into the engine........we'll see.
its trying to clear up. i also have about 5-6 fuse boxes lying around from other toyota swaps, so i decided to swap out some relays, just as a stab in the dark, its trying to come around, better than it was by far. i was able to do a full throttle sprint down the road up to about 80, (guessing, because the speedo still isnt working). i also pulled the no.1 radio fuse out from under the hood, but my head unit is still on......? im guessing the fuse is for the amp? same thing though, shut it off, started it back up, and it idles at 1500 with barely/poor acceleration.
also when i disconnected the old crank angle sensor, i found that the connector was slap full of oil. cleaned out the connector needless to say.
shot in the dark? whats the trans sensors consist of in these cars? are they heavily linked into the ecu, meaning that if a speed sensor goes out, etc., would it cause wierd issues?
also found that the last plug, closest to the firewall on the drivers bank, that little seal that goes around the plug wire insert tube, is pushed all the way in......hmmmm, severe vacuum leak? waiting for the engine to cool now, ill be pulling the valve cover off, retrieving that seal and putting it back in the way its suposed to be, im hoping that, its allowing enough air into that whole that, its directly pulling through the pcv, and its creating a high idle, and also allowing unmetered air into the engine........we'll see.
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fixed the seal.....nope.
but i can say, that now the car is trying to run right, but still isnt. its getting to where it will stumble a bit, clear up, stumble, clear up......
also was able to get it to spit out a code, while it was running right....but under certain circumstances. the trans was replaced in this car about a year ago, by a local performance shop, when the previous customer brought it in to have the coil overs installed, the shop decided to do donuts in it, after the install, in turn, they burnt the trans out. they replaced the trans with a unit directly from lexus.
i have to have my gear selector in a certain sweet spot in neutral, for the ecu to recognize its in neutral. i didnt notice it flashing the cel at me till i looked up, and all i was able to catch was the last number.....3. it didnt repeat itself or anything, and wouldnt give it to me again, after that.
but i can say, that now the car is trying to run right, but still isnt. its getting to where it will stumble a bit, clear up, stumble, clear up......
also was able to get it to spit out a code, while it was running right....but under certain circumstances. the trans was replaced in this car about a year ago, by a local performance shop, when the previous customer brought it in to have the coil overs installed, the shop decided to do donuts in it, after the install, in turn, they burnt the trans out. they replaced the trans with a unit directly from lexus.
i have to have my gear selector in a certain sweet spot in neutral, for the ecu to recognize its in neutral. i didnt notice it flashing the cel at me till i looked up, and all i was able to catch was the last number.....3. it didnt repeat itself or anything, and wouldnt give it to me again, after that.
Last edited by shoob; 08-29-12 at 08:37 PM.
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Hmmm. Wonder if it could be related to fuel delivery? Transmission speed sensor would not cause it to freak out like this. One thing I did see is that 93 was a particularly bad year for the LS400 ECU's. Did you open the new one to see if any of the caps are leaking? Also, I forgot to ask and I don't feel like going back over everything but you have check for spark at each wire right? How are your plugs? Also, are your cats heating up and glowing from unburnt fuel? You mentioned the injectors are really loud. Do you think they are clogged? BG44k is supposed to be a really good cleaner.
Last edited by Lavrishevo; 08-29-12 at 10:54 PM.
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firing on all 8, with new plugs. the ecu i tried came out of a running 93, with no problems at all, as a matter of fact, that car is driving around today. im gonna make a new lead to the crank angle sensor, and try that out.
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BINGO!!
at a first glance, i seen 2 caps busted, replaced them, no help. out of frustration i opened it up again, replaced 2 more caps (4 total). noticed a burnt looking spot on the chip board, visually followed all the circuits then tested continuity to all of them, all good. plugged the ecu in, and im getting a jumpered CEL now!!
code 13.
ok, but i replaced both cam position sensors......
note:
broke out the multi meters.....
getting 1.310 ohms on both cam sensors.....
getting 6.83 ohms on no.2 sensor wires back to ecu.....
getting nothing on no.1 sensor wires back to ecu.
so continuity tested the red wire from no.1 back to the 6 prong combo plug on the drivers bank, continuity is present back to the plug.
tested from the yellow no.2 back to the 6 prong, continuity is present.
tested the green wire from the no.1 plug back to the 6 prong combo plug on the drivers bank, no continuity.
tested the blue from no.2 back to the 6 prong (which blue from no.2 and green from no.1 come together before going to green into the 6 prong) i have continuity there.
so if blue from no.2 and green from no.1 come together before going to the 6 prong as green, then i should have continuity between green no.2 and blue no.1......but i dont. but do have continuity of the blue no.2 going to the 6 prong......
no.2 is the passenger bank though right? so why is the ecu telling me no.2 when no.1 clearly has the issue? do the CAS work in sequence off each other before entering the ecu?
Last edited by shoob; 09-02-12 at 05:41 PM.