filthyphil

Hey all you YotaTech people,

Long time follower, first time poster!
I have a plan to do a full write up thread on my experience with doing the swap but I'll have to work on that another time.
The real reason for this post is I am having major problems with emission and feel like I am at the end of my rope..

Here's some more details:
I live in Golden, CO I have failed emissions once, sense then I discovered that a bearing had rolled and I needed to rebuild, again.
Sent to the machine shop, bought new head gaskets and rebuilt it. I have it running but not the way it should..

1995 toyota 4runner MT 4x4 (3.0 blew head gasket)
ECU and Harness 1996 Toyota 4runner 5VZFE MT 4x4
Engine is a 1997 3.4L for cheap on craigslist (oh boy did I pay for this mistake!)

I did do my own wiring harness, and crossover!

As it sits right now:

Radiator is attached currently just not during photo

Everything is Brand new and everything is OEM Toyota! It was a full rebuild, to get it in the bay after a bearing rolled the first time around...

It runs and everything mechanically sounds fluid!
However, It is running really rich and has some what of a stutter..
The exhaust smells of fuel and it is spitting
No Check Engine light, No codes being thrown

I have done a ton of research on fuel trims, MAF Sensors, EDW's, O2 sensors (A/F sensor)...
This is what my ODBII reading is looking like right now:



Start up is not where it should be, it definitely turns over about five times before it fires
it idles pretty nicely when in Open Loop, just before the fuel system goes into closed loop I can watch the voltage for the Bank 1 Sensor 1 (Upstream O2 Sensor) start to rise up to about 1.000 volt
As this is taking place the short term fuel trims begin to fall into the negatives. Besides that Long Term fuel trims stay at 0.0% and doesn't move at all.
Also Voltage for Bank 1 Sensor 2(Downstream O2 Sensor) stay at about 0 maybe getting to a peak of 0.010 Volts

MAF is reading at .5 lb/min when in closed loop at idle
Absolute throttle position is reading 9.4% at idle
Intake air temperature seems to be reading correctly compared to my phones reading

Everything I have done so far:

I have tested and replaced the IAC gasket and cleaned out the throttle body.
Replaced Water temp. sensor
Replace MAF sensor (Denso) (I did complete the 98'+ MAF swap using the air box and the new sensor, repining the plug to work correctly)
Replace both O2 Sensors (Denso)
Replace Fuel Regulator (Toyota) (Also Checked fuel pressure on Fuel rail and I was getting a steady 40 PSI)
Replaced PVC System (Gasket, valve, and tube)
Replaced Injectors, Wires, Spark Plugs
Replaced Coil packs with JDM Coil packs.. (I checked all Coil packs and Wires for spark today everything was getting spark.
However, didn't seem to be firing correctly, could this just be due to how the engine is running?)

Checked function of Injectors with a 9volt battery to the injectors and checked for proper operation. Passed
Checked function of EVAP system with 9volt battery to connections and checked for proper operation. Passed
Checked Timing and everything is timed correctly.

I have had a lot of problems with fuel leaks mainly at the injectors. The top O-ring gasket has blown a number of times on different injectors, these are brand new!
I have replaced those and I don't seem to be having a leaking issue now. However, before the second rebuild I had issues with that and again with the second rebuild.

Today I got under the truck again and checked Volts at the Upstream O2 sensor.
I was reading over 13volts at W-L wire (+B)??? seems way too high..

I know this is a lot to take in. But any help would be appreciated!!
I have been working for so long to get it here and I really just want to drive it..

filthyphil

So after more research, I am going to pull all the injectors and have them tested at a local shop. Along with that I am going to go through and make sure I'm making good ground connects in the engine bay and in the cab.
Something I forgot to mention which the Injector specialist said was almost definite problem with a injector is at Idle the fuel pressure is 40psi but right after I switch it off I notice the fuel pressure going down a lot faster than it should.

Anyway I'll keep everyone updated

filthyphil

Update:
Wow, aright well after going in and removing the Injectors I see that they are in fact counter fit injectors.. I had purchased these on Ebay, Title stated OEM Fuel Injectors, They came packaged in Denso Boxes and all looked the same, seemed legit. I guess I missed that they didn't actually say Denso on the side...
On top of that the injectors that came with the engine where probably Denso, but i tossed them thinking a had a new OEM replacement...

So New question, Are these off brand aftermarket injectors really that bad? I looked at spark plugs and all had a good coating of Carbon build up. So that would mean that either all are leaking or the excess of fuel would be coming from somewhere else? The intake smells of gas and has some dark carbon build up as well...

hit me with some thoughts. Also where can I purchase Denso Injectors for the cheapest?
I have a local toyota scrap that I trust, If I buy from them and then get them remade locally would that be a smart move for the wallet?

Thanks

filthyphil

Update:

Yesterday I went to YotaYard in Denver, CO, Its a cool little salvage yard that only does Toyota and Lexus parts. Been relying on them pretty heavy for a lot of the odds and ends for the swap.

Went to buy Injectors and Randy (owner of YotaYard) said that the two different style of injectors are specific to what year your ECU is.. I'm running a 1996 ECU so I bought 6 old style injectors. These are grey and look to be made of metal, where the newer style is a brown and made of mainly plastic.

Can anyone confirm or deny that theory?
Because I had the newer style of injectors in the computer isn't able to control the injector as well?? And switching to the older style will hopefully help with my rich problem..

I also bought the older style MAF sensor and a filter that he had lying around. I had done the MAF swap to the newer style and air box. But after talking with Randy and a couple of friends of his they seemed to agree that the swap doesn't work like that and will lead to a rich issue. I had heard differently, I know Mike at ORS (Off Road Solutions) runs that MAF on all of their swaps and hasn't had problems with it..

Anyway, dropped off the injectors to get flow tested. Hope to hear back from them in the next couple of days..

moto809

Does your 5VZ have EGR? My 2001 does not. Just wondering if the emissions tested for the right engine...

filthyphil

Moto809

No EGR Valve on this engine, thankfully. Honestly, I failed emissions so long ago and have done so much sense then. I have mainly been relying on STFT and LTFT and the readings from 02 sensors.
And the smell from the tail pipe. Thanks for the response!

coopster

I have a 99 3.4 and the injectors are brown. Geez I hope mine don't leak, if I ever get to that point.

So that air filter box you have looks like one from a 99. You got it to fit okay, or did you have to cut the bottom off like DNTSDAD?
I started to go that way, but didn't look to fit. Said bad words, now on to trying to come up with Plan B.

What is that tube you used, that replaced the big resonator(?) box between MAF and throttle?

filthyphil

Coopster,

Nice, I believe either 98' or 99' engines used the newer (brown) style injector. So that sounds correct to me. I'm in getting the used injectors cleaned and flow tested. I hope to install and see what happens with that early this week.. Ill definitely post back on the results

I'm using an AirRad Intake Tube that you can find here

I definitely followed DntsDad thread to help with everything fitting into the bay. The guys a legend!
Everything came together really nice following his steps! I used a die grinder and cutting blade to cut everything down on that air box, but could use a hack saw or really anything that will cut plastic! Another thing I did was added a bunch of silicon around the bolts area and the box. I plan to add a snorkel and want to make it as water tight as possible.

Thanks for the response!

filthyphil

Update:

So i ended up buying 6 injectors from a local scrap yard YotaYard and then immediately dropping them off to the Local Fuel Injector Specialist
For anyone living in the Denver area these two places have been a huge help to me with everything would highly recommend doing business with them!

YotaYard checked Omhs on all the injectors 13omhs for each, but one of them wasn't operating correctly so grabbed a replacement for that one and got it back over to the fuel injector specialist.

This is what i got back:

96'-98' Denso injectors


Flow testing and Spray Patterns also got volume pictures as well!

I took advantage of the nice weather yesterday and install everything back in the truck
All I can say is that my truck is running way better!!!
My ODBII readings are looking way better and I no longer have a Rich problem!!!

Well I was hoping that that would be it.. but... I now am running on the lean side of things.. and I have some white smoke coming out of the exhaust.




So, next steps are do a leak down and pray that the heads and gaskets aren't the problem...
I'm also going to check the IAC again..

I hope this helps someone in the future, especially if you are fighting fuel issues! I'll try to report back what I find..

wonkainc

Your fuel trims look good now, great work. My truck flexes to around +20 on the LTFT because I have a fairly shoddy intake setup behind the MAF, and have driven about 5000 miles with no problem. It's easy to end up constantly paranoid about your engine's efficiency with those phone readers. My wife almost killed me over a trip from SoCal to Washington and back for staring at the thing all the time. Toyota CEL tolerance for lean/rich codes is +/- 30%. To be under +/- 15% means it's is not worth worrying about.

Why is your Bank 1 Sensor 2 O2 sensor not reading a voltage? Those two O2 sensors have to agree on what's happening or the ECU will create a bunch of performance issues.
Additionally, what catalytic converter do you have? I ran my truck with a cheap 48 state one and a CA ECU and holy ˟˟˟˟˟ did that create some gremlins.

If you still wanna mess with fuel trim stuff - If you reused ANY vacuum lines for the brake booster, PCV, EVAP, fuel regulator, or ADD system go ahead and replace em. I had a bunch of hoses leftover from the 3.0 that I reused and basically, all of them leaked, so I had an invisible intake leak because everything was leaking. It was a nightmare. Thankfully a cheap and quick fix to try. Also, grab yourself a shopvac and a spray bottle filled with soapy dawn to look for exhaust leaks. I torqued everything and double-checked all the bolts on my exhaust manifolds and crossovers and still had a bunch of little exhaust leaks that threw the O2 sensor voltage a little out of whack.

filthyphil

Man I think you hit the nail on the head!

To start I have been concerning myself a lot with fuel trim numbers. I have seen others say similar things about not looking too deep into what the numbers indicate and more that the ECU is still doing its job and adjusting the engine to optimal performance.. I was hoping to see only about 10% + or - fluctuation on the fuel trims and the more i research, the more i kinda see that isn't always correct..

I bought a cheap direct fit down pipe and catalytic converter off of Ebay.. I ended up cutting it up and welding it to the stock down pipe with the 02 sensor bung in front of the cat. I believe i paid $150 maybe for that federal cat.
The voltage on Bank 1 Sensor 2 has always bothered me.. and after some calling around and some more research. Im leaning towards the Cat is bad, or not responding correctly.

Below are some photos of my ODBII reader, This was after I had driven around the neighborhood for 7 minutes, I would pull into the drive and let it idle. All of a sudden the Bank 1 Sensor 2 starts to respond with some voltage feed back! Unfortunatly I think it is fluctuating too much for being Sensor 2.. correct me if I'm wrong but I thought it was supposed to sit right around .45v?







And then it just dies out again! I was concerned that maybe the brand new Denso sensor was faulty but seeing that makes me lean more towards the cat being the problem.

On top of that, Starting January 1, 2021 Colorado switched to California Emission standards.
So I have ordered the following and going to drop it off at a local muffler shop next week:
MagnaFlow 2.5" in/out Catalytic Converter #447206
MagnaFlow 2.5" in/out Muffler #11226

Also thats a great idea going through and replacing all the hoses. I have tried using other methods of seeing if I have any vacuum leaks. I have yet to hear the idle pick up after spraying starter fluid around all air hoses.. But like you said cheap and easy to go through and make sure!

Fingers crossed the exhaust will help with how the engine is performing and those dang fuel trims. Really want to get this thing registered and on the road!
Thanks for the feed back

coopster

What? Starting January 1, 2021 Colorado switched to California Emission standards

I hadn't heard that. Does that mean testing stations like all the gestapo places in CA?
See what happens when someone leaves the gate unlocked?

filthyphil

Coopster,

Your telling me man.. i wish i still lived in the mountains where emissions aren't a thing.

So as far as I understand it, if it looks like you have a new exhaust system (New after January 1st) on your vehicle then it needs to be running a CARB catalytic converter. Or I guess you can run OEM components too.. I don't understand how they are going to regulate that. Not like they can require everyone to change out their exhaust

Just beware that just about every muffler shop around Denver is charging more than double for those CARB Catalytic converters. I had multiple shops quote me at $700 for just the Cat, ****ing crazy!

I bought the cat and the muffler for a little over $400 off of JEGS.com
hope to have everything installed for under what they wanted for the cat.

wonkainc

As the California kid here, they actually only regulate emissions standards according to the year the vehicle was released. So my 1995 4runner, which is running a 1997 ECU and a 1999 engine, is going to be held accountable for emissions standards in 1997. (because that's how the engine is tuned). So that's nice. Unfortunately, California makes it more complicated because they have nuanced engine swap regulations, which I won't get into here. Additionally, the smog test is only part of the battle, as the CARB (California Air Resource Board) requires all aftermarket parts to have an Executive Order (EO) to say they do not manipulate the emissions system. So in my case, I need a CA 3.4L engine, with a CARB EO list cat, and a CARB EO list cold air intake, or a stock intake. What's worse, is I can buy an intake in a different state that is identical to a CARB EO intake, but because it doesn't have the EO number on it, I'll fail smog. OR if the EO number gets rubbed/sanded/rusted off, they'll fail you. Basically, the smog guys are looking for CARB EO part numbers on all your stuff AND a 'clean' smog test. If your smog guy doesn't pay much attention you could definitely game the system, but you're relying on someone being negligent. What's this mean for Colorado, I have no idea, but it felt good to complain.

wonkainc

Here's an example of OBD2 data with O2 sensor data from my truck, pre-CA cat, and post-CA cat for comparison.

So ya, I agree that it looks like your downstream O2 sensor is fluctuating too much. Those sensors are rather simple heat=voltage machines, so it's safe to assume A. it works & B. your exhaust is being funny. I'm comfortable agreeing that it's the CAT because you can see in both my pre-CA cat and post-CA cat that the downstream 02 did not follow the upstream voltage exactly and was more of a muted version of the same. Your voltages closely match so I'm inclined to think you bought a similar CAT that doesn't have enough catalyst in it to adjust the exhaust to its expected temperatures. Curiously the muffler shop that installed my CA cat said that a Toyota engine will burn out a cat pretty quickly unless the cat is made by a specific company. (pretty sure it was Magna-flow, but I'm not totally sure) Good luck man! I feel your pain trying to get the thing running properly. I ended up just driving illegally with it for about a month, just to properly troubleshoot the issues.

Images originally posted here - https://www.yotatech.com/forums/f160...-3-4-a-307109/

Pre CA Cat - Vehicle runs improperly

filthyphil

Wonkaic

Thanks for your input on this! definitely nice to see some other vehicle's fuel trim data for comparison.

So last week I got the truck over to Mountain Muffler in Golden, CO got it back Friday afternoon, I am very happy with how it all turned out!






The guys at Mountain Muffler did an awesome job! I would highly suggest using them! They tucked it nice and tight to the body, gave me a couple extra hangers too! Ended up adding the 2.5" diagonal SS tip
The Muffler and Cat combo sounds prefect for what I was looking for. On start up it growls sitting in the 1200 RPM range as it warms up and settles it fades off to a really nice soft exhaust sound. But anytime I give it some gas it comes right back to life! Not too loud just right..

filthyphil

In other news...
Im still having some lean readings sitting at idle, and my 02 Sensor 2 is still misbehaving..

Below are some more screen shots of what my ODBII readings
As previously posted my rear 02 sensor 2, is reading very low volts for the first 10 or so minutes..
Then all of a sudden it will start to read voltages. I am however seeing better numbers than before, still No CEL. I sprayed started fluid around the engine hoping to catch a vacuum leak with no luck.







I started to mess with the throttle at this point to see how both 02 sensors would react, and this was the response..



at this point it seems that the 02 sensor 2 is reacting very similar to the 02 Sensor 1

I reached out to a local shop where a Master Toyota tech works and talked with him for a bit.. After asking about the build and what I have done so far, he was concerned that the valves might not be adjusted properly...

He likes to have them loser on the exhaust side and tighter on the intake side.. I did check my valve tolerance, and had a local machine shop shave the stem down to meet spec. That being said, on the second rebuild i lapped the valves one last time, while I was cleaning up the head for reinstallation...
Anyway not my favorite answer, but I can definitely go through and check them some point soon.

Anyone have any other thoughts??

In the mean time I plan on getting emissions tested with the hopes that I pass, I also have a rear brake to fix and some other random tasks to do.
Hope to be driving this thing more to break the engine in

wonkainc

Possible option, and certainly an easy thing to check - verify continuity and harness pin locations for your rear O2 sensor. It's very odd to me that it carries no voltage to the ECU periodically. That sounds like an electrical issue. Could be a short or disconnect on the heater wire for the O2 sensor.

Also, how does it run in general now?

filthyphil

Im working on the truck today so Ill definitely check that out. Gonna have to do some digging to remember how to check that properly but nothing a few youtube videos can't help me figure out

Overall the truck runs really well, its hard to compare when the first time I was driving it around it was running very very rich. That beings said It feels great, but might feel like its hesitating slightly. Also due to it still being under 500 miles on the new rebuild I haven't taken it over 4000 RPMs.

filthyphil

Update:

Great news! I passed emissions!! I now have a registered vehicle again
Emissions was really easy for everyone in CO. I didn't tell anyone at emissions that I swapped the engine, just told them it was a 1995 and they checked out the exhaust, and tested emissions. I was out of there in under thirty minutes.

So I've been braking in the engine by driving around town, to and from work, ect.. Trucks been running good. Still not getting the readings I am hoping, for from the 02 Sensors (Bank 1 Sensor 2) and from the fuel trims. I had a bad brake booster so I changed that out, with hopes of correcting the lean condition, but really my brakes were terrible and the booster had never been replaced. It was time and the brakes feel probably the best they have felt sense I bought the truck 8 years ago.

I started to notice some oil leak coming from the transfer case, which i had resealed nearly at the start of this project. It turns out that there is a special RTV gasket maker for gear oil...
So that was a pretty big mistake but I knew that it will only take me a couple of days to fix. Along with that it gave me an opportunity to check out my wiring to the 02 sensors, and check torques on my exhaust flanges. I got that all cleaned, and sealed back up today.

I tested my wiring at my 02 sensors in hopes of finding a short or something that would identify why my rear 02 sensor has been acting up.
Below is my EDW which is what I followed to do my testing: (The key was turned to the ON position, but I wasn't able to run it due to the transmission being out of the truck)

96 4runner 4x4 manual EDW

Bank 1 Sensor 1:
Pin 1: ((Pink) Heater HT1) - Started at about .7v and fell at a steady rate until it hit zero
Pin 2: ((White/blue) +B 12v) - read at 12.26v (same reading as battery)
Pin 3: ((White) OX1 Signal) - There was a reading of .006v (if I were to back prob this wire while the truck was running I believe i would see a reading similar to my ODBII readings)
Pin 4: ((Brown) E1 Ground) - .006v (seems very low?) Will document how I tested below.



Bank 1 Sensor 2:
Pin 1: ((Red/white) Heater HT2) - Started at about .7v and fell at a steady rate until it hit zero
Pin 2: ((White/blue) +B 12v) - read at 12.26v (same reading as battery)
Pin 3: ((Red) OX2 Signal) - There was a reading of .006v (if I were to back prob this wire while the truck was running I believe i would see a reading similar to my ODBII readings)
Pin 4: ((Brown) E1 Ground) - .006v (seems very low?) Will document how I tested below.



Using my Multimeter, I grounded the negative wire to the negative battery terminal. Then using the positive lead off the multimeter (DC setting) I probed each pin to get the readings. I did this for every pin even when looking for continuity of the ground.. I wasn't totally sure if I was testing the grounds correctly.. If anyone sees anything wrong with my method of testing please chime in!!
After all of this I might be looking at changing out my rear 02 Sensor to see if anything changes...

Along with that I hope to check my valve clearance after I hit the 500 mile mark on the engine brake in. I found out there is a tool that allows to change those with out pulling the engine out again. So I'm going to buy one of those and check that in the near future.