5VZFE Turbo

Glad to hear you got it going!

Interesting you had Fpr issues. Obviously stand alone has more control/avenues than piggy.

The reason I said to use the throttle body port is this mimics stock Fpr signal. The factory regulator is static pressure, with the line to the intake box. It will only raise pressure with altitude this way, and since it is not behind throttle plate (vac) fuel pressure won't go down either when plate is closed.

My truck was adding alot Stft with the signal behind the plate. I came up with using the port in front of plate to simulate stock, only raising pressure with atmosphere/boost. Works great for me and fic.

Good luck with the crank signal, that's a whole different can of worms.

 

The Haltech fuel settings have a check box for static or manifold referenced FPR BTW

 

Just something I noticed after replacing the crank sensor. Engine would not start with the Haltech. I tried another sensor and realized that the first sensor would not seat completely. It would run with the stock ecu but not the Haltech.

 

Yes I have seen many posts too saying that using boost reference at the stock fpr will yield about 4-5 psi fuel pressure increase.

 

Some progress today. Tailpipe is welded on. Tried for hours to tune this trigger problem out with no success. Almost seems like I made it worse. Road testing it would not rev past 3000 rpm. Finally I decided to just rewire the crank sensor harness from the ecu connector all the way to the sensor. I depinned the sensor connector and ran new terminals with a used crank sensor shielded harness I had laying around from a Lexus. Stripped back the factory ecu harness sheathing and found a couple of factory splices, one for the brown wire sensor grounds which was to be expected. What I was shocked to find was a factory splice connecting the cam negative and crank negative wires together about 8 inches from the stock ecu connector. This is not shown on the factory wiring harness schematics either. I eliminated that splice, connected my replacement harness, and the engine free revs perfectly now. I haven’t road tested again due to the laptop going dead. I will follow up tomorrow

 

This is a very interesting discovery. Why do you suppose Toyota would do something like this.

 

Only idea I have is that Toyota thought it would be a good idea to have some redundancy in case the harness was damaged somehow. During my first tuning session I was asked if I had twisted these grounds together while we were having trigger issues. Of course my answer was no because the schematic didn’t show it. Might be something to eliminate for you guys having trigger issues also. I layed down some solder on the other splices as well because they are only a metal band crimped around bare wire. They looked fine but the harness is 25 years old

 

Well shit, guess I'll just run a fresh shielded twisted pair cable out there on mine. Easy enough to do

 

Lets us know how it does afterward. I still need to do a road test but fingers crossed

 

It'll be interesting to see it's road manors. Can you get all the way to the 5500 rpm rev limiter?

 

Sitting still, yes

 

This is great info!
Can you post a photo so I can get an idea where the crimped areas are and where the cam and crankshaft sensor negative wires are joined?
Any bad grounds are kiss of death for the haltech so maybe I will start by soldering
those areas
How did you eliminate that junction?
Did you body ground one?
Or did both negatives get rejoined at the ECU pin?

I uninstalled my haltech today and connected all the stock parts for my Emission test coming up this week.

engine hits 5700rpms with the stock ECU, haltech 5100rpms

 

I should have taken pics but I did not. After 6 hours of screwing around with it I just wanted to fix it at that point. Remember my truck is a T100, but I would think the Tacoma harness is similar. There is a plastic sheath a couple inches down the harness from the connectors with a label on it. Cut that open, save the label though, that is the harness build number that would be needed to order a harness if you ever needed a new one. They are option specific, the VIN is no help when ordering major harnesses. Anyway, the splice was a couple inches into the sheath, simply joining the two wires together and then the two wires continue on to their respective spots in the ecu connector. Think of it like an X intersection. Do not send either wire to body or chassis ground, just cut the splice out and you will have two circuits to connect back together separately.

 

1) Got it, thanks, is this wire coming off the back of one of the 4 plastic group plugs that go into the ECU?
2) were are the wires you soldered that were crimped?

 

1) yes
2) right next to the other crimps, about 8 inches into the harness from the ecu connectors
Do you have a wiring schematic for your truck?

 

Great!
You remember what connector it was?
There are 2 large ones and 2 smaller ones, total of 4.

I was just in there this morning

 

Your wiring may be different than mine. Do you have a schematic?

 

No, but I can probably google it

 

This is what I found. Looks like your ecu might not have separate pins for cam neg. and crank neg. Not sure how how would work that out, without bypassing your pnp harness and going straight to the standalone from that splice

 

Thanks a bunch!
A new crankshaft shielded wire is a good idea