Ali SC3

iTrader: (10)

Good to hear the new tps's worked, I had a feeling it was part of the problem.
So which codes are still there?

A 1uz has no mechanical adjustment of timing, because there are 2 distributors driven by each bank, you wouldn't want them out of synch with each other, so Toyota locked them in place. The only thing that controls the timing is the ecu, but you can still check it with a light to verify, and if its crazy off it could be a bad ecu but I'm thinking you have a bad injector if your coils are good.

checking the injectors is actually surprisingly easy, you just unplug them one at a time until your problem clears up, then you have found the cylinder with the leaky injector. you can also do a resistance test on them however, it is not a sure test, as there could be other reasons for an injector to fail like its clogged or something. Most cases are the coils, but there are a good number of cases of stuck open injectors as well but its not as common as the coils.

Dream36

Ok, there are no codes, just the main o2 ever now and then. It kinda pops up and goes away with the bucking/popping noises.

It is very drivable again now with the new tps's so at least I'm not scared of killing it now. I get paid again on the 15th so I'll pick up a coil or two since they are old anyway. Is it possible that a coil is bad but still fluctuates at speed? I mean they test ok in driveway but once I'm moving it starts up again. That's why I was doubting it being a coil from the door. And when I unplug one it is obvious and the car won't move on either bank.

Anyway, I'm going to test the injectors next. But after I mow the yard. I wasn't expecting to be broke down today after messing it up worse yesterday. I need to make the house owner happy since I was here all day lol.

I'll update thread when I get it figured out. I'm covered in rtv from sealing the intake pipes as they had a few cracks in them (the rubber parts)

Ali SC3

iTrader: (10)

coils sound fine then, as I said I wouldn't replace stuff that doesn't need to it seems like you are almost there, the coils either work or they don't there is not much inbetween for coils. cracks in intake pipes can cause those issues, also the o2 sensor can as well if you are still getting the code popping up after you fix the cracks. by the time the o2's trip off the cel they are probably done for if it isn't due to something else like a bad injector or maf.

Dream36

thanks for the help. I am going to pull the TB and possibly the IM today in order to pull fuel rail and test these injectors. Is there any gaskets or bolts I might need to replace when I begin? Im hoping the o-rings dont rip or crack on me, lol.

I see three well four options

1: clean injectors and service them and hope it helps
2: buy injector (if bad) from autozone $150ish or Lexus $250ish
3: pull injectors from junk yard and hope one works
4: buy the 1000cc (the ones for F/I cars) and install them but use them until I go F/I (about 3 yers)

solution one is my favorite but if it dont work it is a waste of time, option two is not going to happen as I wont waste that kind of money. number three will probably be the way I go if number one fails to fix it. doing the fourth one is a bad idea becasue I would be running those injectors under 50% duty cycle and I know that can cause an injector to fail quick.

anywya, thanks again, I cant wait to get started. btw, she runs better now than the day I brought her home. When I first got her I didnt notice the hesitation but noticed the fuel dripping out exhaust. it could be that it was winter back then.

Ali SC3

iTrader: (10)

you can just unplug the connectors to test them, no need to take everything off yet unless you really want to or can't reach the ones you need to test, but its hard to test them if you can't turn the motor on if you have everything off. you can do 1-3, but for #4 you will need a standalone fuel controller for 1000cc injectors which are expensive for the 400, the stock ecu cannot control much past 440's with a simple fuel controller I think.

Dream36

yeah I agree with all you said. I can bench test them off the car but ultimately i wont know unless i test with motor running. problem is the passenger side is completely impossible to reach. the driver side I checked all four cut power as soon as i unplugged them so I know those four arent the issue.

and yeah I am looking at a stand alone, I wouldnt want to do piggy back on this car once I do go F/I anyway.

Ali SC3

iTrader: (10)

oh ok, as long as you know what you are getting into, the standalones for the UZ are not as common and usually alot more expensive than the JZ stuff.

another thing you can do to rule out the o2 sensors before you do all that is disconnect the main o2's at the wire clips, and then reset the ecu and see how the car runs. It will run rich but if it runs smooth it could be faulty o2's causing your issue. especially also if right now with them connected if the problem is not there when you first start the car, and then it comes after the temp gauge starts to go up, that could be a sign its o2's as well. If the problem is always there I would lean towards faulty injector or ecu.

Dream36

thanks for the insight. I just happen to have a 19mm sitting here at work, so Ill probably pull it out clean it then plug the whole with the sensor unplugged. if it doesnt hesitate or skip or pop on the way home you nailed it. I do happen to have 4 O2 sensors from a corvette motor that was in my RX7 I can give a try. they are the Bosch universal kind (high and low signal with prewarmer)

Ali SC3

iTrader: (10)

no need to remove them unless you like extra work. just unplug them and I doubt you are getting them off with a regular 19mm unless you are taking them off after warming up the exhaust to operating temp cause those things get stuck on there pretty good. I usually do the run the motor shut it off and immediately take them out (long sleeves help for not burning your arms), but if its somewhere where you will burn yourself do it cold, but you will need the proper o2 sensor socket get the short thick kind at the auto store, the really long ones are thin and usually skip threads before untightening anything making the sensor even harder to remove IMO they are junk and flex too much.

good enough to use a breaker bar on


absolutely worthless and more often than not strip your o2 sensor

Dream36

update: It was the cats, first they were just bad but now they are completely clogged. I am going to fix this today and tomroorw. So for those seaching and findign this, remember to check those cats