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View Full Version : Getting nowhere and could use some help



hhojoe
07-09-2008, 08:35 PM
Evening all, been trying to get a handle on controlling the car's computer and all it has been doing is frustrating me.

A little background...
The car is a 2006 Subaru Baja Turbo. My generator can be seen at youtube if you search for "hhojoe". This weekend I switched to NaOH and production is up to about 800ml at 18 amps. Not the greatest but for what I have to work with (space limitation) I'm pleased for now. The HHO gas is connected to my air intake tube after the IAT and MAF sensors and as close to the turbo as I can get.

Now the PITA... First I tried no sensor manipulation, after resetting the PCM my mileage was great until the PCM 'learned' then mileage went into the toilet. Reset the PCM, mileage goes up for about 20 miles then bam, down again (monitored via a laptop).

Next I tried a MAP sensor adjuster to reduce the voltage the PCM sees and with the voltage down to about 2 volts my mileage is back to stock, for a while. Then I tried a MAF sensor reducer. This has much more of an effect on the engine where if i turn it too far I can stall the engine. Impressive, but mileage gains are practically still at zero.

Using a program on my PC and an odb-2 cable I am able to log data from many different sensors and it seems that my manual sensor adjusters have an effect but inevitibly the PCM ends up compensating in some way. Right no I have both the MAF and MAP adjusters in place. Next thing I am going to try is attacking the O2 sensor but of course its not a regular O2 sensor, that would be too easy, the forward sensor is an Air/Fuel Ratio sensor.

I've considered purchasing the proper odb-2 cable (already have the software) and redoing the mappings but the drawback there is, what about when the generator isn't running?

If you would like to see any logs, graphs or are curious about anything else such as the build of the MAP or MAF adjuster I can certainly fill you in. At this point I am very open to suggestions on how to handle the PCM.

rules
07-17-2008, 02:04 PM
Hey Joe

I'm also thinking of installing a HHO generator into my car, but I'm worried whether the Volvo (2001 V70 T5) will fall for this trick :) It can adapt the normal ecu as well as the controller for the gearbox to suit your driving, so I can foresee the same thing happening as in your case.

The thing that bothers me is that my IAT sensor sits after the turbo (next to the pressure sensor) and I'm worried that it might somehow ignite the gas. No one has been able to tell me whether it will be safe or not, and it seems a bit dangerous to just try and see.

Have you had any good results on your side yet?

Cheers.

Smith03Jetta
07-17-2008, 02:10 PM
I ran the Vag-Com software today and pulled all my engine codes. I have a few codes in there that were caused by me messing around with the O2 sensor and MAF sensor. One code says my O2 sensor grounded out. Another says my MAF sensor signal went out of range. The MAF sensor also caused an engine stall that was recorded in my car's computer. Now that I've turned off all the electronic "TOYS" that I was using to play around with different signals and focussed solely on reprogramming my car's computer I need to clean out all the engine codes and start over again.

hhojoe
07-20-2008, 08:30 PM
rules - People were telling me initially that i was crazy for using hho on a turbo. Between the heat of the turbo and the added pressure, they said I was asking for trouble. But when you take a look at the following I couldn't see why it would be an issue:

Fuel - Autoignition Temperature
Hydrogen - 1085 ºF (585 ºC)
Methane - 1003 ºF (540 ºC)
Propane - 914 ºF (490 ºC)
Methanol - 725 ºF (385 ºC)
Gasoline - 450 to 900 ºF (230 to 480 ºC)

I used this info to decide whether or not to run hho on my turbo. This and the fact that we are injecting perhaps 1LPM of hho gas when the engine is gulping liters upon liters of air in the same amount of time. Just how concentrated can the gas be? Will the molecules burn off before it reaches the cylinder? I don't think so and besides, the oxygen also assists the engine. So after running it for a few weeks now both gingerly and in boost and monitoring my engine with ecuedit software, I've not felt or registered any ill effects.

Funny stuff that hho. When monitoring the engine I can clearly see by the graphs when I turn up the hho and turn it off. The rear O2 sensor goes lean with it on and the injector duty cycle then rises (along with other senors changing). So far I've manually compensated the MAP, MAF and front O2 sensor all to no avail.

Now the next hurdle, bought a tactrix cable which allows me to read my ECU but my ECU isn't very popular and the maps are not available. I am told they will be in August so until then I'm going to read up on how to lean it out using software. Guess I can keep a cheap laptop in the car to reflash the ECU if the hho genny gives out. Or, I can just try the whole setup in my '03 Nissan with a dumber ECU...

rules
07-21-2008, 02:31 AM
From everything I have read so far I'm not that worried about the "gas side" of things any more, but on the other side, I'm now even more worried about getting the ecu to work properly. I recently "spoke" to someone that knows the Volvo's management system pretty well. I was actually looking into doing some software mods myself but was warned that there were literately thousands (something like 20000) of pieces of software that would have to be changed (and that was only for increasing boost) and not only that, you would need to know where to find all those pieces too. Apparently the Bosch ME7 ecu on this vehilce can calculate thousands of different maps depending on certain conditions (outside air temp, intake air temp, torque request - has electronic throttle, boost etc. etc.). All this tells me that if I ever go ahead with this, I will have to trick the sensors into doing what I want.

Let us know if you come up with a good solution :)

hhojoe
07-21-2008, 07:52 AM
Some guys over at NASIOC, a Subie site, run with their ECU's in open loop and just change the base maps to their liking. In a lot of ways I am inclined to agree with them after all computers don't know everything. Are there many (or any) volvo tuning sites out there you can research?

kiwibrick
07-21-2008, 08:22 AM
Volvospeed for the FWD & AWD ovlovs