RESOLVED: S/C Installation Prob, Rough/High Idle Issues and Rats (Code P0125)

Fuel pump testing completed. I was able to rig 18 gauge leads into the factory harness and connected to a battery. Submerged the pump in a 5-gal bucket of water and connected to a fuel pressure gauge, then ran for 1-minute. Volumetric output is on spec with the 190 LPH pump rating (actually pumped 228 LPH). Pressure reading was in excess of 30 psi - but wasn't totally capped off so I couldn't get an accurate max reading. I'm thinking it was well over 60 PSI. Ran some gas through the pump to clear any water afterwards.

Time to put the gas tank back in and retest fuel system pressure. But that sounds like a job for tomorrow.

Nice, sounds like you can completely rule the pump itself out
 
Rats!

Thread update. With the fuel pump ruled out, I was just about to rip out my S/C and reinstall it. Maybe I'd find something I installed incorrectly...

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And then... I saw this!

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Damn rats ate through my #1 fuel injector wiring connector. I replaced that and I was now running on 6-cylinders again. I also replaced the IAC while I had the throttle body off. Cleaned 20 years of throttle body grime off and professionally modified the throttle body gasket to match the S/C opening. Sorry, Toyota - I'm not paying $30 for something I can dremel myself.



I also installed the CA smog-legal S/C pulley - big thanks GameFreak - and did my best to hide the URD (non-legal) 7th injector kit. And because I'm funemployed and have nothing better to do with my time, I also removed my skid plate and put a baywatch / David Hasselhoff shine to it.

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I was just about to claim glory and bragging rights here by not taking my 4runner to a mechanic and completely DIY'ing it. Until I drove it around the block and got a P0125 code happening (Insufficient Coolant Temperature for Closed Loop Fuel Control). Also, idle is smooth but inconsistent. Sometimes it chums along at 700 RPM and at other times it is at 1300 RPM. Doesn't matter if the engine is hot or cold.

GameFreak has some ideas - maybe a bad coolant sensor reading incorrect inconsistent coolant temps. Also would explain the frenetic idle range.

Lastly - product review for these Harbor Freight's LED magnetic light thingies. These things are awesome. I bought three of them and don't know how I've been able to wrench all these years without good lights. They'll magnetically attach to any steel surface, then you can rotate in any direction. Engine pics taken above with lights on. Sadly, I found out my 300zx has an aluminum hood and they wouldn't stick #fastcarprobs.
 
RESOLVED! Passed Smog Today, All Issues Cleared

This has been a long and winding journey to resolution. Many probs, some things I fixed that didn't need fixing, meeting some great people on the boards, and a bunch of other adventures I've been on the last few weeks.

Problem overview:
- Rough/High Idle Issues
- Fuel System / Misfire Codes (P0125 and others)
- Can't pass CA Smog and register vehicle due to CEL light

Background:
- First Gen Grey Supercharger Installed by me.
- URD 7th Injector and Control Unit installed by me.
- Vehicle had been sitting for 2 years.
- Codes galore since S/C was installed in 2015(?), history of lean codes.
- Family of rats used my 4runner as living quarters for who knows how long.

Remediation:

Rough/High Idle Issues
Cleaned MAF and settled down rough idle. Prior to cleaning, engine felt like it was gasping for air. After cleaning, smooth idle at 1500 RPM. Humming along but still a lot of engine vibration.

Further investigation yielded a cut #1 cylinder fuel injector harness. Inch of wire was missing - RATS. Spliced in a new harness. Adding more detail in my 'lean codes' resolution.

Idle dropped from 1500 to 1300. Removed throttle body, cleaned it. Installed new Idle Air Control Valve (IAC). Idle settled from 1300 to 700 but would occasionally creep back up to 1200 and then all over the place for no apparent. Reinspected throttle body and adjusted throttle tension. Idle sits smooth at 700 now, resolved.

Lean Codes
4runner was throwing lean codes since S/C was installed. Don't have the exact codes since I didn't have a code reader at the time. I could spray starting fluid into the airbox and make them go away for 2-minutes. This was 2-years ago and I was off to a job in Chicago. Fixing 4runner probs was the least of my worries.

Checked fuel pressure and was thinking this might be part of my issue. Maybe I had a bad fuel pump. Tapped into the 7th injector fitting with a fuel pressure gauge and read 10 PSI. Pressure from pump should be around 60 psi. Took fuel pump out of the tank and bench tested it. Hooked up a battery to fuel pump with water in one 5-gal bucket and measured how much water was pumped into another 5-gal bucket in 1-minute. Walbro fuel pump rated at 190 liters per hour. Fuel pump was able to pump 220 liters per hour exceeding posted specs.

I'm thinking the 7th injector is tapped into the fuel pressure return line downstream of the fuel pressure regulator. I'll find this out at some point. It certainly was fun reinstalling a fuel pump. Glad Toyota decided to make you drop your fuel tank to remove a fuel pump. Just, you know, to help you build character.

P0125 code - Insufficient Coolant Temperature for Closed Loop Fuel Control

This is a terrible mystery code that does not actually explain what the prob is. This is Toyota's code for not having all air / fuel / engine temp sensors talking to each other correctly - or something like that. Typically, it is thrown when an O2 sensor goes bad. Or the Engine Coolant Temp sensor goes bad, or some other sensor goes bad. I replaced all of them. Didn't fix my prob and was still throwing code.

My wife did the awesome wifely thing and made me an appointment at the dealership for me. Maybe, probably could have saved some money and taken it to an independent shop, but I needed to have this fixed now and was willing to pay a premium to have it done right the first time.

Diagnosis and fix: ECU indicated there were 4 open connections (broken wires). This was caused by stress on wires from my installation of the URD Engine Control Module - module is stored in my glove box. 6-hours of labor and $830 later, tech identified 9 connections that were broken or suspect and repaired. Also, tidied up all the cables and wiring, made it look like a professional install.

Lesson Learned: Do not stress wires. I didn't think I was especially rough with them during my installation. Also, package them up nice and neat so they don't rub or cause problems due to normal vehicle vibrations from use. I will be paranoid about this for the rest of my life now.

CA Smog Learnings and Notes
I managed to make several trips to my local smog testing shops over the last few weeks. CA emissions are annoying as all can be. CA now requires every vehicle to have a sticker for all TRD superchargers or any aftermarket parts you install on your car placed in the engine compartment. I say 'now requires' because something happened in the last few years where you absolutely need the sticker or your car will not pass. It's not good enough bringing in executive order documentation or other proof of compliance. I went to multiple smog testers and they all said the same thing.

So, not having a sticker and in a bind, I called my local Toyota dealership and asked if they could reprint me a TRD Supercharger emissions sticker. They look like this:

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Dealership informs me that stickers are no longer in production and I could fill out a form online for an exemption. Parts guy at Toyota then goes on to give me a link to where I can download the executive orders... the one I already had printed out. Obviously, not a solution to the administrative problem I was trying to solve.

I gave up and decided to photoshop my own stickers and took them down to a local print shop for printing. Slapped one on my engine compartment and passed smog without the smog tech inspecting pulley size, 7th injector or other potentially non-compliant mods. He just needed to see the damn sticker.

So, if anyone needs a sticker for your S/C to pass smog in CA and don't have it. Let me know. I have extras printed out or can send you the photoshop file if you want to print them yourself. I'll put another post up on this.

Thanks again to all of you that have helped, especially gamefreakgc. 4runner is getting plates next week and I'll be able to explore Northern California in a street legal, registered vehicle.

TLDR; shit works now, passed smog, thank you everyone!
 
Cleaned 20 years of throttle body grime off and professionally modified the throttle body gasket to match the S/C opening. Sorry, Toyota - I'm not paying $30 for something I can dremel myself.

You can get a paper one for under $3 or a teflon one for under $8 from LCE Engineering.
 
For sure. The amount of relief when I was finally able to walk into the DMV and get plates! Now to explore all of Northern California before I have to get a job again.

Let me know if you find any fun trails in the nearby area! A lot of guys on here do more hardcore trails like the Rubicon, Fordyce, Eagle Lakes, etc. that my stock height rig can never do so I don't know of many trails in the area.
 

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