Jacque766

When I bought it the Hydra 2.5 was already installed. I've been looking around but can't get a clear answer on some questions I have.

I know it uses a built in MAP sensor, but does it still read the OEM sensors?

For example the MAF, its just hanging there, does it still take the temp reading if it's hooked up?
Would the stock ECU try to compensate for any readings? Or does the hydra block the signal completely and I should just unhook it?

J~

equinox2355

Well the hydra allows for temp readings from the maf, but basically this is how its hooked up:

stock wiring harness (sensors and everything) -> Hydra -> Factory ECU.

The question that I would have, is what modifications are on the car?

Jacque766

I noticed the OEM AFR sensor was missing and the secondary O2 Sensor was just hanging there too.

The downpipe has a mounting spot for the supplied wideband (only 4 inches from turbo which to me seems to close), ....but I read a comment that said after tuning is complete disconnect it because you dont use it.

How does the ECU do any compensating if both OEM 02 sensors are gone and the hydra L2H2 is unplugged?


Should I by a 02 sensor bung and weld it onto my S-pipe for the stock 02 sensor?
Should I weld a spot for both sensors?
Should I keep the Hydra L2H2 sensor installed even though I'm not tuning the car just driving it?

J~

Jacque766

MODS:

HKS GT3040 BB Turbo 50-T exh side, .70 A/R (Water and oil cooled)
750 cc RC Injectors (No other fuel mods)
4-1 Equidistant exhaust manifold, (not log style crap)
3" piping all the way back (no cats)
FMIC
HKS EVC IV
HKS Racing Blowoff Valve
Turbo Smart Pro Gate-48 Wastegate

Jacque766

So after you have a desired MAP saved then it dosnt use the OEM sensor readings during normal operation?

OEM Oil pressure sensor is missing too

It's just strange to me because all these sensors are the "brains" of how the engine is responding so if they are all hanging in mid air or unplugged.....how is the car even really running.

Or surprise....that's the catch it can't be used as a daily driver.....?

It starts fine, pulls good, but it's rich for sure.

Should I down grade to the 550 cc injectors since the engine is not built up and 750cc is just overkill?

toyota_scion_tc

Too many variations that can be causing the car to run rich, but boosted rich is a good thing. You want it to run rich to keep EGT’s down and leave room for error, how rich are you talking about?

Ace83

iTrader: (6)

Ok i havent read all your post.. but yeah hydra uses most of your oem sensors.. who did you have it tuned or who installed it?

1. MAF will not be used, except for the temp reading.. if you get the hydra AIT sensor, you can disconnect the maf,

2. Stock primary O2 sensor is used for close loop. if you have the hydra O2 wideband, you can remove you stock O2 sensor and use your hydra O2 sensor. secondary is not used. you have that setting that allows you to use the stock or the hydra O2.

You can also run open loop all the way if you disable cloosed loop, that means no O2 sensor used.. i

3. thats about it. Leave your other sensors on.. but who did the install???

Ace83

iTrader: (6)

ok I see that you have the hydra wideband.. now you can disconnect the 2 oem O2 sensors.. the instructions says you disconnect the hydra wideband after tuning, you can do that if you choose to use the oem O2 sensor.. you can also use the better hydra wideband, just put it on the right setting.. if you have target table configured then set it there. You can disconnect the hydra wideband only if you use it for autotuning but have the option to leave it there and use it daily

rhythmnsmoke

Stock motor? Exhaust manifold custom made?

equinox2355

I was told something interesting by my tuner, that the HydraEMS wideband sensor is that it is very accurate, however it does not last long at all. Pretty much it is really good for tuning but not for normal usage (unless you want to keep replacing it)

Ace83

iTrader: (6)

yup and expensive.. but i didnt know that it doesnt last that long, maybe some who have been using it for awhile can chime in.. putting it not too close to the manifold might solve it

Jacque766

Dynamic Auto Sport in So Cal did the tuning and installation.

You mentioned the "Primary" 02 Sensor should stay connected.....Is that the one that is called the "AFR" and screwed into the old manifold?

Or when people say primary....its the one behind the cat in the S-Pipe?

The "AFR" (manifold) one is gone. The wiring harness is empty. The one in the S-Pipe is just hanging there. Didn't realize it for about oh....400 miles! so its probably busted now. But I have to get a bung and weld it in because the S-pipe was replaced with a 3" inch flex pipe.

So to clarify then during normal day to day driving the Hydra is still using readings from the sensors to adjust fuel curves ect. So I need to get my 02 sensor in ASAP and mount the MAF as well. Can the MAF be installed in the charge pipe?

Don't have the AIT sensor...but considering it if the MAF is better left out of the picture.


With my old eclipse general consensus was to never have the Wideband closer than 14" and further away than 34" for a good reading on the down pipe and to minimize damage.

Jacque766

Not sure how rich yet, but low MPG (18 highway) and fouled plugs means too rich to me. I have the AEM EUGO wideband ready to get installed as a second backup but I'm still waiting on 02 Bungs so I can mount these sensors.

EGT will be in the near future.

What is a good EGT reading at idle, car warm, 900?
Cruising 1300?
And don't go over 1600?

J~

Jacque766

Stock motor? Exhaust manifold custom made?[/quote]



Stock motor. Exhaust manifold was custom made. From engine....4 separate pipes (not log style) that loop down about 9" and then back up into a 4-1 collector and then to the turbo mounting flange.

J~

rhythmnsmoke

^^how much did that run you price wise?

Ace83

iTrader: (6)

aight let me clear things a lil, we have the 2 stock o2 sensors, primary the one next to the manifold is one that adjust fuel based on the afr it reads secpndary only checks if cat is working
you need to forget about the stock ecu, all engine managemnt is done by hydra.
on your car, it seems that your tuner used the hydra wideband o2 sensor instead of the stock ones.. as long as the settings are right you can leave your stock o2 sensors out. now if you dont have the ait sensor from hydra you need to hook your maf sensor but the only signal it reads now is jist air temp. hope that makes sense

Jacque766

Its over 10K. Just adding the parts its close to 7k and that's wholesale prices.

J~

Jacque766

If the settings are for either the stock 02 or the hydra 02, then at least 1 has to be installed correct for day to day driving? Right now neither are installed .


Where are people mounting there MAF? Can it go in the charge pipe or does it have to be protected from boost?

Ace83

iTrader: (6)

You mean the hydra O2 sensor and the stock primary and secondary sensors are not installed too? so no O2 sensor installed?

most mount their maf at the intake pipe but the better way to do it is on the charge pipe..

daym for over 10K with stock motor it better be very well configured and awesome tune..

how bout posting pics of your setup so we can see it better

Jacque766

No 02 Sensor Installed. I'll have to get some time to look at the setup on the hydra and see which one I should be using.

The setup is beautiful, the parts are top notch, and the welds and fitment is great. You can clearly see a lot of R&D was done, it's just the sensors issue. The claim was that "countless hours" were spent on the Dyno... and its not that it doesn't run great right now, I'm just trying to learn as much as I can so that I know everything is flawless.

Having a little background on Turbo setups I know its very important to be able to know and adjust your EGT's, true AFR, Fuel Pressure, ect.....I've never used a standalone before so that's why I'm full of questions. I'm use to tuning with a SAFC, Wideband, and Vortech SFMU.


J~