LScowboyLS

no, checking the O2 sensors is easy, no harm in that, although the resistance check will tell you nothing about how responsive they are - if they are original, they should probably be repalced, make sure an use genuine Nippon Denso O2 sensors only, should be able to find for around $50 if you are a good online shopper!

here is the thread on the ECU capacitors

python

iTrader: (4)

what would u have to remove twice? nothing about the 2 jobs are related
if ur knock sensors need replacing ur going to fix the wires at the ecu? lmao
u asked for advice..i have been down the knock sensor road,been there done that...long ago. if ur knock sensors are bad,which im not saying they are..u will have to determine if they are..then i suggest u take my advice and do exactly what i suggested..btw standing on the side of ur front fenders to see which head is furthest forward,thats the head that has the #1 plug/cylinder..thats on any v-8
also dont listen to cowboy..he thinks every symptom is caps related

duballstar

In your first post you said nothing about standing by the fender (and still you don't reference which fender drivers or passenger). I think you forgot to include some important information referencing orientation. Anyway, I understand what your saying.

I don't think you are following what I mean with the knock sensors. I have one working sensor and one broken (hypothetically speaking, wiring or sensor itself). I would tap into the working knock signal (at the ECU) and splice in the second signal that leads to the ecu. In turn I would have one working knock sensor sending the proper signal to a split that would feed both knock sensor inputs on the ECU. This would completely disregard the broken sensor/wiring (what ever it may be). I would do all of the wiring inside the cabin right before the ECU to avoid removing any engine parts. Do you follow?

Cowboys information is definitely well thought out, but I will trouble shoot the oxygen sensor first and go from there. Thanks again for all the input guys. Now I just need some time to actually get my hands dirty.

duballstar

Update

I had some time this weekend to start troubleshooting/replacing parts on the car. The first thing I did was read the codes and still came up with CODE 28 and 55. Afterwards I cleared the codes, and did another reading to see what would initially come back, which only was CODE 28. Next I disconnect the negative battery terminal and got started. I put the car up on ramps and jacked the rear end up so it was completely level. After getting everything settled in I grabbed my 7/8" wrench and removed the old oxygen sensor. The sensor was not very tight in the bung, which leads me to believe this was done before. After getting the clip disconnect and pulling the sensor out, I compared it to the new one.



The tip was white, but the wiring harness side looked to be a little moist from P/S fluid. The contamination was probably slowing the reaction time of the sensor, in turn, destroying it. It might be time for a new rack.



After the sensor was tightened down and plugged in. I decided to drain the oil and change the fuel filter. I usually am a sole believer in MOTUL lubricants from France, as I used to be a distributor for them, but the Mobil One will have to work this time. The dude at Autozone hooked me up with a filter for free to.



While the oil was draining I took the time and started gaining access to the transmission bushing. I dreaded this job because with my previous experiences on S-Chassis cars, the four bolts holding the transmission bracket up would always be so hard to line up. Unlike my S13, this was a piece of cake. I started by using a piece of wood to jack the transmission up from the bracket so there wouldn't be any stress on the mount. Next, I unbolting the four 12mm nuts that hold the bushing to the bracket. Next I loosened the four 14mm bolts that hold the bracket to the car. Now with the bracket off and the bushing accessible I removed the four 12mm bolts holding the bushing to the transmission. Here is a picture of all the components:



Comparison of old mount to new. It didn't look that bad on the car, but after getting it out you could definitely see the sagging and wear.



I almost went genuine Lexus for the mount, but now that I see how easy it is. I would recommend an OE style. The fit was perfect and cost was almost half. The only thing that had to be done was one of the holes that bolt the bushing to the transmission had some slag in it and would not receive a bolt. I grabbed a drill and cleared it out and it was good to go.



After re-installing all the bushing hardware and changing the filter, I was ready to fill it up and start it. I reconnected the battery, put her on all fours, and fired it up. After getting fuel pressure from the removed filter, it started right up with no CEL. I took a drive around the block and about 5 minutes into the drive the CEL came back on. I pulled the codes again when I got home and only got CODE 55. The car drove a whole lot better. I didn't feel any hesitation under partial throttle and it even felt like the transmission was shifting smoother. The highway rattle/shaking/rumbling was gone and it honestly felt like a whole new car. Night and Day difference.

I still have to diagnose the Knock Sensor CEL, but I am happy with the outcome so far. Thanks again for all the help and hopefully my experiences can help someone in the future. I will report back with more updates on the remaining codes.


Fun information that isn't related. I scored some CROW ENTERPRISES harnesses and harness bar for my S13 this weekend too. I can't wait to try these bad boys out at the track in 2 weeks.

duballstar

Just wanted to follow up with my initial code diagnostic. After driving ~3k miles on the new oxygen sensor and transmission mount, I am very happy with the results. The violent shaking at ~45 has yet to occur again and the oxygen code did not come back on.

Now time for Code 55, Knock Sensor Two.

As I stated previously, I plan to splice into the proper working knock sensor and feed both ecu pins to keep the computer happy. After finding many conflicting results on ecu pin outs, I finally made the decision and started splicing and soldering.

I ended up using this as a reference-

http://www.lextreme.com/lexuecc2.pdf

I found the 16 pin connector and sourced out the two BLACK WIRES for knock one and two. My harness actually had a GRAY wire, but all worked out in the end. I drove the car around and the CEL stayed off.

Here is the ECU:



Some soldering action:

Lavrishevo

iTrader: (1)

You can try but this does not work with 02 sensors and no reason to think it would work with a knock sensor. Let is know if it stays off.

http://www.magnumtuning.com/en/produ...nsor-simulator

duballstar

Not sure what you are referencing. Those resistors are for tricking the oxygen sensor signal, making it think there is a catalytic convertor inline.

The car is running great and no CEL. If anyone is still confused about how I wired the knock sensors and would like more information, feel free to ask. Its very simple, but it doesn't seem like many of you understand it.