96 ls400 misfires
03-26-20, 03:54 PM
#1
Driver School Candidate
Thread Starter
96 ls400 misfires
I've got a 96 ls400, 250k. I got it, it had a code for a misfire on all 8, plus drivers upstream 02. Replaced 02 sensor, all wires, and had the injectors rebuilt, there were mechanically ok, but the seal on the manifold end was shot on them all. Compression was 170 ish psi across all 8
Currently I have misfires on 1 and 7, with the occasional 2 thrown in. I'm thinking the cap and rotor. That passenger side looks... Fun... To get off.
I've swapped plugs around, swapped could around, with no changes.
Basically the car runs like total shirt. In park it runs fine (now, especially after injectors) but in drive, and say pulling out, you can really feel it miss, but isn't terribly sluggish. Once it hits about 3k rpm though, it really cleans up.
Was thinking maybe the ECU cap issue that's stickied?
Currently I have misfires on 1 and 7, with the occasional 2 thrown in. I'm thinking the cap and rotor. That passenger side looks... Fun... To get off.
I've swapped plugs around, swapped could around, with no changes.
Basically the car runs like total shirt. In park it runs fine (now, especially after injectors) but in drive, and say pulling out, you can really feel it miss, but isn't terribly sluggish. Once it hits about 3k rpm though, it really cleans up.
Was thinking maybe the ECU cap issue that's stickied?
Last edited by Nhyrum; 03-26-20 at 04:36 PM.
03-28-20, 12:27 PM
#2
Driver School Candidate
Thread Starter
So, it idles great cold. Once it gets a little warm, it idles like horse manure, smokes, and smells like raw fuel. I can't see any fuel leaks. Any ideas? Getting misfires on 1,2, and 7.
03-30-20, 12:24 PM
#6
I've got a 96 ls400, 250k. I got it, it had a code for a misfire on all 8, plus drivers upstream 02. Replaced 02 sensor, all wires, and had the injectors rebuilt, there were mechanically ok, but the seal on the manifold end was shot on them all. Compression was 170 ish psi across all 8
Currently I have misfires on 1 and 7, with the occasional 2 thrown in. I'm thinking the cap and rotor. That passenger side looks... Fun... To get off.
I've swapped plugs around, swapped could around, with no changes.
Basically the car runs like total shirt. In park it runs fine (now, especially after injectors) but in drive, and say pulling out, you can really feel it miss, but isn't terribly sluggish. Once it hits about 3k rpm though, it really cleans up.
Was thinking maybe the ECU cap issue that's stickied?
Currently I have misfires on 1 and 7, with the occasional 2 thrown in. I'm thinking the cap and rotor. That passenger side looks... Fun... To get off.
I've swapped plugs around, swapped could around, with no changes.
Basically the car runs like total shirt. In park it runs fine (now, especially after injectors) but in drive, and say pulling out, you can really feel it miss, but isn't terribly sluggish. Once it hits about 3k rpm though, it really cleans up.
Was thinking maybe the ECU cap issue that's stickied?
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03-30-20, 01:49 PM
#8
Driver School Candidate
Thread Starter
Did you keep your original spark plug wires? If so, take out the new ones and re-install the originals. I've found out the hard way, several years ago I replaced my original wires with new ones and that was a big mistake, the new ones were crap. Fortunately I didn't throw away my original ones, so I took out the new ones and reinstalled my originals, the misfire issues disappeared. The aftermarket wires are in no way nearly as good as the originals, I now have 270k miles on my original wires and they are still going strong. Unless you have a specific problem with the original wires, I would never replace them. In my opinion, nothing comes close to the quality specs of the original oem wires, unfortunately they don't make them anymore, at least with the same quality imo. Good luck.
03-30-20, 02:29 PM
#9
To clarify, are you saying the "original" wires were too short? Were all 8 original wires in bad shape? Once again, I strongly urge you to reinstall the original wires "if" they are still in good shape, I would only replace the bad ones, but certainly not all of them based on my experience. An easy way to check would be to remove the spark plug covers, start the engine and observe the wires in the dark to see if sparks are coming from them, if you notice any sparks then the wires are leaking voltage that;s being grounded by the engine before they reach your spark plugs which is why you're getting the codes effecting almost all of your cylinders. I'm not 100% sure this is your problem, but it certainly was my issue. Good luck.
03-30-20, 03:37 PM
#10
Lexus Champion
I've got a 96 ls400, 250k. I got it, it had a code for a misfire on all 8, plus drivers upstream 02. Replaced 02 sensor, all wires, and had the injectors rebuilt, there were mechanically ok, but the seal on the manifold end was shot on them all. Compression was 170 ish psi across all 8
Currently I have misfires on 1 and 7, with the occasional 2 thrown in. I'm thinking the cap and rotor. That passenger side looks... Fun... To get off.
I've swapped plugs around, swapped could around, with no changes.
Basically the car runs like total shirt. In park it runs fine (now, especially after injectors) but in drive, and say pulling out, you can really feel it miss, but isn't terribly sluggish. Once it hits about 3k rpm though, it really cleans up.
Was thinking maybe the ECU cap issue that's stickied?
Currently I have misfires on 1 and 7, with the occasional 2 thrown in. I'm thinking the cap and rotor. That passenger side looks... Fun... To get off.
I've swapped plugs around, swapped could around, with no changes.
Basically the car runs like total shirt. In park it runs fine (now, especially after injectors) but in drive, and say pulling out, you can really feel it miss, but isn't terribly sluggish. Once it hits about 3k rpm though, it really cleans up.
Was thinking maybe the ECU cap issue that's stickied?
Did you use aftermarket caps & rotors?
OEM plug wires fit perfectly avoiding problems.
Verify Toyota North America did not supercede part number from the original spark plug wire set....
Inquire about country of origin.
Last edited by YODAONE; 03-30-20 at 03:41 PM.
03-30-20, 03:48 PM
#11
Driver School Candidate
Thread Starter
On this last drive, the misfires changed to 302,307, and 308. With the trim running real negative, -20-30 sometimes, I'm thinking it's the maf? Which I've cleaned, twice, using a whole can each, with the unit out of the car, let it sit for a half hour before reinstalling and plugging it back in. Maybe a bad o2? When it gets warmer, it really runs rough, idles with white smoke and has that raw fuel in the exhaust smell pretty strong
03-31-20, 01:43 PM
#13
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03-31-20, 01:48 PM
#14
Driver School Candidate
Thread Starter
What I've learned. Nobody actually knows how to work on these pieces of junk. Oh yeah, fuel filter is supposed to be here. Crack the lines, let the extra fuel out, 14.. 17mm and 10mm nope. Filter in a different place, with battery disconnected and fuse out, fuel ran for a half hour with no signs of slowing, so now I'm covered in gas, with a still unfunctioning piece of ****, which I get to figure out how to replace the right side multi function switch cause I ripped the ****er out