CLRH2O

You and I seem to be having the same issue. In my case I'm checking out the IACV - currently I get all your symptoms PLUS the car has no idle unless I unplug the Intake Air Control Valve (the black round thing at the front top most point on your engine, attached to the intake housing), take it off, take it apart, manually turn the plunger to about the 3/4 open position and then reassemble, re-install and LEAVE IT unplugged.

The deal in my case is, if I let the car's ECU actuate the IACV, it just closes it up and never opens it again... in which case I have all the issues you have PLUS it dies instantly if you take your foot off the gas.

https://www.clublexus.com/forums/per...acv-sc400.html

So - I'll be following this thread closely, and I'll try to add to it myself as things are learned on my end.

Quick aside - I had my ECU rebuilt (new Capacitors... not sure f they are ones described by a flat out ECU genius here on the boards or not... but it's only been like 10 months since the rebuild so I'm assuming it's still good) - and that didn't fix anything - literally - nothing (of the many problems) with this car was effected for the better at all - even though my original ECU had about 4 completely splattered capacitors inside of it.

Austin2048

Thank you. I really appreciate your input. Were you getting a code 13 as well? That's the only code my car is throwing now. But earlier this morning I was doing a bit of highway driving and I noticed that my cel turned off if I was going 70 or faster. The car also seems to drive completely fine at 70. But as soon as I got back to in town driving the cel came back on and it was bucking again and it would die if I was sitting at a stop light too long with the car in drive. It was fine if I kept it in neutral but as soon as I'd put it in drive to get going it would die.

Ill try what you suggested tomorrow morning when I get home from work and hopefully that helps.

Austin2048

Here's a little update.

Today I tried cleaning the iacv but that failed. The 3 screws holding it together were very rusty. I got 2 out but the 3rd one stripped to all hell. So I cleaned the outside as best i could and it didn't make a difference.

I investigated the code 13 a little farther. I took everything on the passenger side apart and saw that the cps wire was getting pinched by the cam cover. The rubber coating was a little torn so I repaired that. I put my ohm meter on both cam sensors and they are both within spec. Car is still running like poop and throwing the code 13.

What is the possibility of the wiring between the cps plug and the ecu having a fault? I tried to trace them but its difficult without tearing everything apart again.

What gets me the most is when I first got my 2000 Camry it was throwing a code for the cam position sensor but it ran totally fine. When I looked at the sensor I noticed it was just hanging there by a loose bolt. When I bolted it back up to where it was supposed to go the performance of the car didn't change at all. The only thing that changed was it stopped throwing a code. I realize there's quite a big difference between the 1uz and the 5s-fe but why would a cam sensor fault on the camry not affect performance but on the 1uz it does?

CLRH2O

One doing it, and the other not would come down to what the ECU chooses to do based upon what the engineers of the engine felt was the appropriate *thing* to program it to do when that fault is encountered.... But as to *why* on one and not the other. Man, we'd have to be part of those engineering teams to get that answer I'm guessing LOL

CLRH2O

Just out of curiosity - but have tyou done the 12v fuel pump relay mod yet? You say it's running great at highway speed (70mph) but not at city speed. It's my understanding that our fuel pumps have a low speed setting (using 9volts) and a high speed, or high fuel volume setting using 12volts. And the 12v mode is engaged at higher RPMs and such when the engine is need of more fuel.

I know it's a shot in the dark - but maybe do a quick search on it here and see if it's anything you'd consider.

And forgive me if you have and it's already been mentioned in this thread - I haven't looked back again to verify n____n

t2d2

iTrader: (8)

I ended up answering my own question when I stumbled across this thread in the LS400 forum:

https://www.clublexus.com/forums/ls4...capacitor.html

I've got new capacitors on order and found someone local that can do the work. $10 shipped for twice as many capacitors as I need for the project (might as well have double of everything, just in case), plus whatever bill the tech rings up. There's no point chasing gremlins elsewhere in the system with the likelihood that the ECU is either already problematic or soon to be, given how cheap the capacitors are. If you're competent enough to do your own circuit board work, then it's pretty much pocket change.

Shrugy

iTrader: (12)

I had a similar problem, and all pointed to the coil packs.

I later found out there was a crack in the spark plug wires causing it to misfire in one of the chambers.

I had all symptoms you experienced and while going at a constant speed or slow acceleration it got real bad.

Hope this helped!