Running issues and P1054 Plague

[DomiNATE]

Hope everyone is well.  I've learned a bit since my last post about my issues but I'll explain where I'm at.  

My car 280z with a 99' firebird LS1 and a 4L60E trans is constantly getting getting a P1054 error code (checked with a diablosport intune, i only use it to check for codes, I need a more comprehensive scanner).  When the code/check engine light comes on the car seems to lose power/struggle and miss when I hit the gas, just makes a bunch of racket, it gets around ok if I don't hit the throttle too hard.  I made it to the gas station about 2 miles from my house today and the symptoms popped up, I've made it 20 miles to a car meet 100% and then on the way home from the meet the symptoms return.  

I'm open to suggestions of what to do.  

Now if you feel like reading, here's what I've done...

1. When I bought the car it didn't want to start but when it did, it got around.  After scanning it a Cam sensor code came up.  Turns out the Cam and MAP sensors were UNPLUGGED.  Plugged them in and the check engine light went off for about two days and now I'm basically having the same symptoms I am now.  (i drove the car 150 miles to OCMD like that btw before I knew those sensors were uplugged)

2. Talked to a friend who's done a few LS Swaps and gave me some things to trouble shoot.  First I relocated the 02 sensors directly under the header collectors, they were about a foot down the pipe in what he described as a lazy installation. 

3. My symptoms made him think the car might be starved for fuel (hesitating and struggling under load on the road) so I inspected my fuel system.  The main fuel line on the car appeared to be a braided 5/16 line and it was kind of a mix of sizes to get it plumbed between the fuel tank and the pump.  The car also had an MSD fuel pump rated up to 40psi... I thought I hit the jackpot... I ordered the complete PSI Conversions LS Fuel kit (25' of line, proper fuel pump *Much quieter than the MSD piece of crap*, fuel filter/regulater and all the 6AN fittings your heart could desire.  Finished the install this week and fuel pressure at idle improved from 58 to 61psi.  But after all that, here I am, still chasing this stupid issue.

Here is where I'm at...

I currently have the spark plugs out of the car to inspect them and the wires.  They are all an MSD wire/boot (gray/black) set specifically for an LS but one has brown boots and is visibly torn at the plug connection so I'll definitely replace that.  The plugs look ok and are NGK TR55 gapped between 55 & 60.  I don't see any obvious problems other than that boot.  Was googling for the correct spark gap and found this update for the Spark Plug Wire Gaps https://www.acdelcotechconnect.com/pdf/tsb/tsb_03D-J-171.pdf 

Well I just looked up my plugs and TR55 (gap at 60) plugs ARE NOT listed as being specifically for my year motor however some old ass LS1.com thread had guys in 2008 running the TR55 on their 99-02 firebirds. The 3 plugs on NGK's website THAT ARE what they sell for the 99' V8 all say to gap them at 40.  Perhaps NGK made the adjustment to their website a long time ago when the service update was released.  Is it possible I'm over gap and having misses and that's throwing the o2 code because of improperly burnt fuel on the 02 sensor? or would the the computer throw a different code? I'm not sure how specific or complicated ECU's will throw codes.  I literally might just have the wrong plugs in my car... 

Any thoughts would be appreciated. 

[DomiNATE]

Thanks for the tips  So I changed the spark plugs to new E3 plugs and got an all new set of MSD 8.5 plug wires and installed them, they were the same plug wires as before but one was different and damaged.

I cleared the P1054 o2 sensor code, fired it up and the car ran great. No hesitation or anything.  I took it for a ride to the grocery store and things were great. 

On the return trip the check engine light came back on however the car seemed to continue to perform well.  I stopped at the end of my street and let it rip before I got home and all seemed well.  The code was the same P1054 code.  My diablo scanner doesn't tell me much, just says, "o2 sensor no activity" or something.  I need to get a more comprehensive scanner when I get some money saved up.  

I'm going to consider that o2 sensor code a ghost or glitch in the matrix unless I notice a drop in performance.  

[Richard Oben]

Ohm out the wires on the O2 sensor or replace the sensor.  Based on what is said above there is a chance the O2 sensors are not the correct ones.  HTH, R. 

[DomiNATE]

6 hours ago, Richard Oben said:

Ohm out the wires on the O2 sensor or replace the sensor.  Based on what is said above there is a chance the O2 sensors are not the correct ones.  HTH, R. 

Thanks. Is there a Ohm sensor brand or meter you recommend? I’m not familiar with them.

I’ve already replaced both o2 sensors with the newest Delco ones so I think they’re right. They had different part numbers because one has a longer wire than the other but that shouldn’t matter right? 

I THINK this issue started because when i got the car the sensor was mounted in a way where the wire rubbed the frame and it wore through the wire. Even after replacing them both I still get this code. I forget which bank and stream the more comprehensive scanner showed as being dead. I could use advice one a good scanner as well. 

[Richard Oben]

Any decent voltmeter will have a continuity tester on it.  Test all the wires to see if the connector at the firewall has continuity with wire where the sensors plug in.  Also check voltages, I could guess but LS1 Tech will have them for sure.  Hope the link works it was the first one I found.  R

https://www.amazon.com/dp/B01FU6YFFE/ref=asc_df_B01FU6YFFE5237467/?tag=hyprod-20&creative=395033&creativeASIN=B01FU6YFFE&linkCode=df0&hvadid=198075247191&hvpos=1o1&hvnetw=g&hvrand=2553055293416806656&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9023204&hvtargid=pla-320025484721

[DomiNATE]

On 10/28/2017 at 8:42 AM, Richard Oben said:

Any decent voltmeter will have a continuity tester on it.  Test all the wires to see if the connector at the firewall has continuity with wire where the sensors plug in.  Also check voltages, I could guess but LS1 Tech will have them for sure.  Hope the link works it was the first one I found.  R

https://www.amazon.com/dp/B01FU6YFFE/ref=asc_df_B01FU6YFFE5237467/?tag=hyprod-20&creative=395033&creativeASIN=B01FU6YFFE&linkCode=df0&hvadid=198075247191&hvpos=1o1&hvnetw=g&hvrand=2553055293416806656&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9023204&hvtargid=pla-320025484721

Cool thanks.  I'm friends with a snap-on guy so he let me borrow one of their Mobius(?) scanners which looks like it can do a ton of stuff.  I'll findings when I get a chance to mess with it.

[SH4DY]

Do you mean P0154? P0154 O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 1) 

https://www.amazon.com/Autel-MaxiScan-MS309-Diagnostic-Scanner/dp/B001LHQBMC/ref=sr_1_13?ie=UTF8&qid=1510758097&sr=8-13&keywords=obd+code+reader <-- I keep one of these in my truck. It'll show you codes and live data.

I agree with checking the wiring in the harness for continuity. Is it a stock F-body harness or was it modified? They could have crossed a wire or one might have broken if they extended plugs or something. 

 

[zboi]

Well you could continue to just blindly replace everything, or you could just hook up a logger to the car and see what is actually happening. Seeing as how you didn't even notice your map sensor unplugged before, I think its safe to assume the wiring on it is questionable. You may have swapped your front O2s with the back O2 plugs or something or cut some wires, or not have the power hooked up to the sensor.

[DomiNATE]

On 11/15/2017 at 10:05 AM, SH4DY said:

Do you mean P0154? P0154 O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 1) 

https://www.amazon.com/Autel-MaxiScan-MS309-Diagnostic-Scanner/dp/B001LHQBMC/ref=sr_1_13?ie=UTF8&qid=1510758097&sr=8-13&keywords=obd+code+reader <-- I keep one of these in my truck. It'll show you codes and live data.

I agree with checking the wiring in the harness for continuity. Is it a stock F-body harness or was it modified? They could have crossed a wire or one might have broken if they extended plugs or something. 

 

Yes that's the correct code, figures i miss typed it.  Thanks I'll look into that item.  Gonna be tied up for six months in training before I can though.  The car has a stand alone PSI aftermarket harness with 2 o2 sensor plugs.  I think a sensor wire may have been extended, I'll remember to look into that down the road. 

 

 

On 11/22/2017 at 7:42 AM, zboi said:

Well you could continue to just blindly replace everything, or you could just hook up a logger to the car and see what is actually happening. Seeing as how you didn't even notice your map sensor unplugged before, I think its safe to assume the wiring on it is questionable. You may have swapped your front O2s with the back O2 plugs or something or cut some wires, or not have the power hooked up to the sensor.

It's my first venture into anything fuel injected or LS and I don't know much a lot about motor repairs much less electronic wiring so it has taken some time getting familiar with the car.  I didn't build the motor or do the swap.  There was an o2 sensor with a worn through wire so I thought that would have been an easy fix but the car had bigger issues keeping it from running well and I sorted them out, this is just the last on the list.  It's got an aftermarket PSI wiring harness with two o2 sensors so that's pretty impossible to mix up.  I'll check the wires down the road when I have time.  

[DomiNATE]

So I figured out what was wrong with my car and posted it on my instagram a while back when it got worked out.  Well I didn't figure it out, I took it to someone who knows what they're doing with LS motors.

 

Short version = the PSI wiring harness was hooked up wrong (by PSI I assume).  

 

Long version = May 2018 I was recommended to a guy who races a fox body mustang with a 90 something mm turbo LSX on the weekends and is apparently good with LS style motors.  He plugged the car into his HP tuners program/laptop and was immediately curious as to why the o2 sensors closed-loop function was basically tuned out or deactivated.  But he started with testing the wires.  He found all the ground wires he could going to the motor and tested them, they were all good.  He then swapped the o2 sensors to see if the code would switch sides, it did not switch sides.  He tested the ecu he had by swapping in a spare ecu he had and it still had the same issue.  He then thought that maybe the wiring harness was plugged into the ecu wrong, and it was!  The o2 sensor wires were in the wrong ports of the plug that connects the harness to the ecu, they got power and were grounded but they couldn't send any signals.  The following is all assumption but I think the previous owner bought the stand alone harness from PSI and immediately had problems.  I think he didn't figure out exactly what it was and perhaps had a local shop do a diablo tune to the car and somehow deactivated the closed loop function of the o2 sensors to get around the issue of them not being readable by the ecu, (the car ran great under full throttle *open loop* with this issue), perhaps the  harness being hooked up wrong just caused this itself .  After checking his phone real quick for the correct harness diagram he reconnected the harness wires to the ecu properly and the sensors came to life.  He then did a road tune to get everything back to normal and the car has ran great since.  

 

Looking forward to hopping on here more and learning about differentials and axles and all that good stuff to beef up.  Also looking to get a t56 transmission in the car at some point too.

 

PS,  PSI is on my 💩 list because of this.  Unless the old owner had to pull the wires off the plug of the harness to get it through the firewall then PSI hooked it up wrong from the start.  I also bought their external fuel pump kit which is $460 bucks and they don't pack it with a genuine WIX filter/regulator and that failed within like 3 months.