Sluggish performance.

[dewme5]

Just took my swap for a test drive last night.

1uz (40/40/40) with A341E that I pulled from a junk yard last week from a 92 SC400. Unfortunately, there were no signs of serious accident on the vehicle, so why it was relinquished to a junk yard, I do not know. It was delivered to the yard just a few days before I stripped it, so I think injectors will still be fine, and all seem to sound good, but was unable to check cold start inj. yet.

Engine harness is unmolested, and connectors from the body harness clipped off and utilized.

Ignitors are grounded.

Starting is a little rough. crank - nothing. crank - sputter, crank -sputter, crank - 1 sec of running, crank - runs, give 1/8 throttle to get it moving, after about 5 seconds, I can take my foot off, and it idles super smooth.

Was not aware this was a learning computer, and I kept removing the negative battery cable thought the process. I'm sure this only magnified my problems.

I know I have an exhaust leak about 1 foot away from the main passenger o2 sensor. Also, I do not have the after cat o2's. exhaust is pretty high on the back pressure scale for right now, as it's running thru a 2" single after the transmission (stock 95 nissan pickup muffler and tail pipe).

Test drive. Reverse was smooth, back out of drive way. Shift (stock SC4 shifter with no wires connected to it) into forward easily, and immediately remember I need to hook up the power steering asap.

Auto shift at about 2500, seems a little sluggish. Stop sign, turn right, shift into 1, and again it auto shifts about 2500 on it's own, so I just move it back to D, and leave it alone. Give it about 40% throttle, I feel like the engine knows I want it to accelerate, but acts like a 4 year old being told to go to bed. I know i have to, but I'm going to drag it out as long as possible.

Hit about 45mph, shifts into 3 and O/D all on it's own. Pattern basically repeats. I would guess running a 1/4 mile, I could hit about 60 or so. This is in a 2200lb mini pickup. It should be MUCH snappier (the 2.4l in it was).

Fuel pressure is on high pressure all the time (direct wired fuel pump).

I am assuming it's in limp mode, and certainly needs to "learn" before a full evaluation. Is this something the secondary o2's missing could cause? Leaking cold start (will restart immediately if you shut off, and try again, but wait 2 min, and it is hard to start again).

Anything else stand out as being wrong?

 

[dewme5]

Seems the secondary o2's might be "a" cause of the limp mode.

Credits to nigelwade on oldschool.co.nz
"two o2 sensors operating as four

On a customers car today (05/12/2011) I cleared the sub o2 code by connecting OXR2 directly to OXR1 and OXL2 directly to OXL1. I did not connect the heating wires (e.g. (HTR2 to HTR1 and HTL2 to HTL1) there was/iss not any point in doing that since it wont clear the code at all. This cleared not only the sub o2 errors I was getting. But it also cleared the primary o2 code for the left bank that I was getting previously, although I had gone to several hours worth of effort to resolve that issue so it might be that I had resolved that and not known it, (I was ripping through the job to finish up so I did alot of things over 10hrs in one day). However, the end result was that only code that was left was error code 56, which is the hydrostatic fan (which I de-pinned), it had no effect, and the car ran great (actually it ran VERY well). This gives the ecu two fake secondary o2 sensors (ghost ones), the problem is that there is no difference between them and the primaries, there should be a difference between the values that the primary and secondary o2's put out in a factory engine. However, it clears the code, removes closed loop mode (limp) and hey, thats the goal.

Note: this was tested by two other installers on the 6th and 7th (Dec 2011), both reported that it clears the code and closed loop (limp mode).

... These extra o2's are not normally included in with the engine, they are actually bundled into the body/chassis harness because physically they are after the cat

... tend to find the wiring for secondary o2's on post 95 engines, and only when I get a full and complete loom. It’s not a major, the issues just need to be addressed because I think that causes the engine to run in 'limp/default mode' which sounds bad but it's fine a wee bit less power, bit less fuel economy but its not hugely noticable, just clear the code one way or another and be 100% sure it's running great. "

 

[dewme5]

Alright. Progress has been made. I work out of town, so I only get to get this project going on the weekends.

New install, and trying to get things going one by one.

Having now idea what limp mode feels like, I couldn't tell if that is what I was experiencing or not. Well, turns out it was not.

Left coil was close on all measurements, but not in range on any. Started pulling plug wires one at a time. left coil wasn't doing anything. Back to the junk yard to get another one, and replace it. Starts running much better, but there was still a misfire. Look a little closer, plug wires were not on correctly. 4 and 6 were swapped as well.

Now, power is good. I tried jumping main and sub o2's together on left and right sides. that didn't seem to do much, and still threw codes, so Ill need to check that again tomorrow.

Now, it's time to start tiding up the wires, and making things look better. I think most of my problems are now sorted, and it is certainly driveable at the moment.

 

[dewme5]

New problems. some with solutions.

Hydraulic fan pump - siezed up after about 30 mins of driving. Stopped complete, forced the serp. belt to break. Pain in the butt to fix on the side of the road. I removed the pulley and pump, and bypassed the A/C, using a short belt. PN. 6PK1575 (62" or 157.5cm I believe"

Overheated a little as well. Was using a standard starter solenoid for the fan relay, and that has quit working, so I'll need to find a more appropriate relay.

Averaged about 22mpg on the maiden 3 hour voyage in stop and go traffic. Using the auto A341E, and unknown rear gearing. I do have a problem with early shifting currently. I've not adjust the shift kick down linkage, and have not even separated the tranny from the block.

I'm lacking most all guages, so I might need to pull the stock ones from the donor car instead of going all aftermarket. Unsure on this one, as I plan to Megasquirt, and boost. I might just run NA-T.

 

[milisakeracing]

Sounds like you're starting to make progress. As far as I know, the OBD-I engines do not need the sub-O2s to run properly but the ECU will continue to throw a code for it.

Just delete the hydraulic fan stuff all together and go electric.

What fuel pump are you using?

As for exhaust, I ran 2.5" from each bank to just past the transmission, then joined via a 3" y running to a 3" single in/dual out muffler. The y and the muffler are both made by magnaflow. Get lots of complements on the sound of the car and there is probably more restriction in the manifolds now than the rest of the exhaust system.

I'm currently in the middle of swapping out the stock ECU for a MS3 setup and headed down the twin turbocharged road.

 

[Smitherz]

I used Adaptronic and still love it. A tad more $ than the Mega but much easier and faster to hookup and drive. I used mine as a daily driver for a long time. My heads are heavily ported so I basically had to run the new ecu. Stock computers also run great and provide the best tune in all situations unless you are really good at tuning and love to fiddle and experiment I would advise using the stock ecu.

Just pick up a cheap relay somewhere. I wire mine negative pull so it just takes a simple switch providing a ground signal to trigger it. Carry an extra in case the one craps out. It happens more often than you think with aftermarket relays. Only gauge you need is a water temp. You know it has oil in it by filling it up of course. Good luck.

 

[dewme5]

All the hydraulic fan stuff is now gone.

Fuel pump, is the stock one for the nissan pickup. I don't detect a lack of fuel with my butt meter, however, I'm staying out of the high rpms for now. I plan to run some boost in the future, and know I'll need to upgrade.

Exhaust is an embarrassing combination of pipes right now, and only as a functioning tide over for now. I have a few turbos laying around, including a pair of matching CT26's from Supra's. I just need to figure out which way I'm going to go, then build a good exhaust after that.

I'm at a toss up between keeping the stock ECU, and maybe using the AEM f/ic, doing a NA-T setup. I would prefer to go MS3/extra, or I've even been looking at the spitronics setup. Close to the same money as MS3, but already setup for the 1uz.

In the end, I want mild boost, very street-able and very reliable. I like having an automatic, but I'm not sure this A341 is going to do it. I snipped the shift/anti-squat solenoid wire (pink with black stripe), and it did make a difference that feels good, it didn't take care of any issues. When I leave it in drive, in traffic, it shifts into second after about 10 feet. Really. Then it doesn't want to down shift into first if you mash the throttle while in second. So, either take off like you mean it, so manually shift.

I'm sure the trans could use a flush, I put in new fluid, as the yard had drained all that it would give up. So I've got a good portion of fresh fluid in there, but a full on flush needs done.

 

[Smitherz]

We have members here using stock ECU and adding on fuel controllers / AIC piggyback style to their turbo 1UZ's. Check around. Going that route is very reliable as they drive them every day and they are fast. It just consumes a whole lot of your life tuning an aftermarket ECU properly. You don't need me to tell you. After doing it myself I am in awe of how well factory ECU's work in all conditions on all the cars we have running around us. =I

 

[XR8tt]

Get a decent ECU and tuner you'll be fine..
Half hearted, bodged tune often ends in grief..
There's a reason ECU's over $1.5k work better..

 

[milisakeracing]

Fuel pump, is the stock one for the nissan pickup. I don't detect a lack of fuel with my butt meter, however, I'm staying out of the high rpms for now. I plan to run some boost in the future, and know I'll need to upgrade.

I do not know the spec of the Nissan fuel pump but it may not be providing adequate pressure and flow volume for the 4L 1UZ since the previous engine was only a 2.5L engine.

 

[dewme5]

I've not used all the horsepower yet. I have to change rear ends, fix a trans mount, and a few other little things before I try to get crazy. I doubt I've been over 5500rpm in first gear.

Getting it running, and making it to work are the important things. Now, with a baseline, and knowledge that the engine functions well, I can start to improve, weekend by weekend.