HFS-6 Inconcistent Injection
 

Hi everyone,

I have recently purchased a Hilux with a 3.4 TRD supercharged motor. The motor is setup quite nice, with some headwork, pulley geared for about 9 psi, seventh injector added, and exhaust. It is also running a HFS-6 system. I am very new to the water injection world, and want to learn as much about these units as I can. From what I understand the HFS-6 is known to have a few issues.

I have a few questions in regards to my setup, and hopefully you guys can help me out.

- First question is, on the display gauge, 90% of the time I can only get the unit to flow 2 bars, no matter what the boost or engine load conditions are. Occasionally I will see the flow bar going higher, and indicating it is actually flowing more.
- Second question is I beleive the unit is injecting too early, even when highway cruising, most of the time the blue LED, at the end of the bar graph is flickering (not sure what that LED represents) and will flow one or two bar on maybe 2-3 psi.
-Third question is, after I leave the car overnight, when I start I can hear what I beleive is the pump has possibly lost prime. I can hear quite a growl coming from the car, but havent been able to pinpoint it to the pump. The fluid tank is above th epump, so should gravity to the pump. Are there any issues with the pump from the HFS-6 losing prime? The pump has an accumulator (I think they are called) on it, which I beleive the later models dont have.

I would also like to re-do jet size calculations etc to confirm that I have the right jet etc, but I can work on that later.

Thanks, Josh

Re: HFS-6 Inconcistent Injection
 

Hello Josh,

HFS6 is the most complex and versatile system we have ever produced, issue is normally associate with the operator not familiar with the system. Quality of the install is great affected by the longer term reliability of the system. It was superseded by the current HFS3 and 4 in 2012.

First of all, how old is the system? A newly installed system should not exhibit those abnormal behaviour.

First thing to do is to purged the system and check for corrosion of the wires. If the pump is installed in the engine bay, you will have no end of problems as it is not suppose to be. There are more experience users here on the HFS6 that may chime in and help. I can only help you with the initial problem and not effective on a six years old install.

You first call for support is from your supplier.

Re: HFS-6 Inconcistent Injection
 

Hi Richard thanks for the reply!

I would imagine the system to be around 3-4 years old.

The pump is currently installed on the underside of the car, under the tub. I do not like it there and am planning on installing the pump, wiring and a reservoir in a small weather proof tool box in the back of the ute.

Yes I have been in contact with the supplier and installer a while ago, so I will find out some more details from them as well.

I think in the long run I would like to upgrade to a HSF3, but can't afford that cost right now. I presume that nothing would be interchangeable with the HFS6.

I will research into purging the system, and go from there.

Josh

Re: HFS-6 Inconcistent Injection
 

The pump is not water proof, in time it will fail as the bearing are corroded. You might like to replace the pump and relocate it to a dry place.

Re: HFS-6 Inconcistent Injection
 

OK thanks for that, its is possible that it is on its way out now.

i found some details on the kit, it was the owner of the car who purchased it, and had a mechanic install it (performance shop) but I don't know if they have had a lot to do these type of sytems (ie they advertise the fact they install them etc).

Will a newer model pump replace the pump I have now?

Re: HFS-6 Inconcistent Injection
 

My current thoughts at the moment are to purchase a new pump, and an aquamist baffled water meth tank, and install in a dry protected area. Whilst I'm at it install an inline filter and jet with checkvalve as the jet is currently located on the supercharger intake, with no check valve.

I would also like to look at the option of changing jet size and running just water through the system, along with dropping a few psi (stock pulley) form the supercharger.

Josh

Re: HFS-6 Inconcistent Injection
 

All available at the online shop.

Re: HFS-6 Inconcistent Injection
 

So i have finally had a chance to try and tune and run this system. Took for a quick drive to see how the system reacted with the "tune" that was already in the controller. Threshold was set to maybe 20%, and everything seemed to work OK, although I could only get it to display 3 bars. No worries, pulled over and put the jumper link on cal, and adjusted the bar graph. While i was there i adjusted the fail safe trims to 12 o'clock,put jumper back on PRK, took for another test drive and kept going to fail safe.I noticed there were no flow bars lighting up though.

Pulled over and adjusted the fail safes to full anti clockwise on WL and full clockwise on WH (i presumed this would almost eliminate failsafe??) and took for a test drive. I could see the B symbol light up as soon as threshold was met, no fail safe activating but no flow bars would light up at all.

Returned home and put unit into test, had full flow out of the jet, but no bar graph displayed. (im presuming the flow sensor is playing seized, is there anyway I can test?) Is there anaything else i should check?

Thanks

Re: HFS-6 Inconcistent Injection
 

A little more testing this afternoon revealed that the unit is still spraying, had jet onto windscreen. No bars on graph. Put into test mode and couldn’t see any bars. Would the sc pot full clockwise and it would show 3 bars?? I thought this direction should tune it to display no bars. Turned it back to where I had it set 6 bats under cal mode, and nothing. Have the fcm a light tap and one bar showed up. I think the fcm may be faulty, connections seem to be ok fiddles with them all and didn’t see a difference.

Is there anyway I can clean the FCM?

Thanks

Re: HFS-6 Inconcistent Injection
 

intermittent could be caused by internal corrosion of the FCM. Post a picture of the inside.

Re: HFS-6 Inconcistent Injection
 

Thanks for the quick reply, how do I access inside of fcm? It has foam on the mounting surface,to reduce vibration I suppose, are there screws there to gain access?

Thanks

Re: HFS-6 Inconcistent Injection
 

four screws

Re: HFS-6 Inconcistent Injection
 

Photos from inside, tested again after reassembly and have a maximum of two bars reading for no more than two seconds under TST mode with jet spraying into bottle. Sorry if photos are too big doing this from my phone

https://image.ibb.co/c9fwhb/7_A51_E8...5350_DE077.jpg

https://image.ibb.co/hRZ08G/BBA892_B...AD2_CBAAF3.jpg

https://image.ibb.co/hLK08G/7_DB865_...41_BFFFE26.jpg

Re: HFS-6 Inconcistent Injection
 

I have also run trough my calcs for jet size. Original installer had 1mm jet installed.

240cc injectors x 6 + 440cc 7th injector =

1880cc/0.15 (water or 50/50)=

282cc/min water meth=

0.5mm jet

Does this seem right? There is no boost compensation in jet pressure as water is injected pre supercharger.

Josh

Re: HFS-6 Inconcistent Injection
 

Richard have you got anymore suggestions for me? There doesn't appear to be any corrosion?

Regards Josh

Re: HFS-6 Inconcistent Injection
 

Looks very clean to me. Good.

What are the flow results of a 1mm nozzle for 1 minute?

Looks clean from the outside. I wonder how clean is the internals, FAV and flow sensor. Do you use distilled water?

One more possibility for inconsistency. Since the pump is not water proofed. The internal bearing may be partially seized and cannot generate a proper pressure. Can you remove the pump head and check the pump bearings.

Alternatively, splice in an inline 300psi pressure gauge, and check if the line pressure is around 160psi.

Re: HFS-6 Inconcistent Injection
 

Haven’t done a times flow test yet, will do that soon and report back. Will be with the 0.8mm jet as I recently changed down to that.

Yes always use distilled water, I will go over the pump and see if there is any corrosion. When I have put into TST before, the flow seemed to be solid with no variance in flow for the whole test period, this was for quite a few minutes as I ran nearly two liters through it. How does the flow sensor work? Is it an external sensor? I can only see cabling going to the circuit board, nothing going to flow sensor, or is it a paddle wheel and Hall effect type arrangement?

Will report back soon.

Josh

Re: HFS-6 Inconcistent Injection
 

Flow sensor is the hall effect type. It senses the rotating speed of the magnetic turbine within the metal tube.

If flow is not steady under TST test, pump is the prime suspect.

Re: HFS-6 Inconcistent Injection
 

That is understandable, when i was in TST mode though it wouldn't register at all, apart from an intermittent spike every now and then of 2 bars. makes me think the sensor wheel may be sticking. is there anyway i can pull it apart and inspect? havent had a chance to do a one minute flow test yet.

regards

Re: HFS-6 Inconcistent Injection
 

Bit of an update of some work i have done.

I tested the cc/min of the installed #8 jet. It only pumped out about 260cc. The chart shows at 160psi should be near 460cc/min. This is indicating to me the pump could be failing.

I pulled the flow sensor housing apart and everything was free, blowing through the unit with my mouth i could feel the trigger impeller spinning. This is telling me the it either isnt spinning due to reduced pressure or flow in the line.

Next step will be to pull apart the pump head and check for signs of corrosion etc.

Other than that, i can only assume that the flow sensing circuit has failed.

Josh

Re: HFS-6 Inconcistent Injection
 

Another update,

I have pulled apart the pump, haven't found any signs of corrosion in the pump, bearings etc look fine, spins freely by hand. The diaphragm looked really clean as well.

I am not sure of the anti surge unit on the outlet of the pump, whether it could have blockages etc. Is this unit necessary, i notice the later pumps don't have it.
Looks like ill need to wire in a pressure gauge and see what pressure is coming from the pump.

Is there a way to test the hall affect sensor on the printed circuit board?

Is there a minimum flow that the sensor will only work on. I presume that if i get 260cc a minute, that the sensor should read this, as with a smaller jet installed 260cc/min is achievable.

What pin on the gauge is the flow sensor trigger?

Regards

Re: HFS-6 Inconcistent Injection
 

the flow sensor may require cleaning. There is a filter between the tank and pump.

Re: HFS-6 Inconcistent Injection
 

I have a full hfs6 that I’m parting out. I bought it 5 years ago or longer and never installed it. When I tried to use it this year the Ethernet connectors on the circuit board are loose or something and it wouldn’t function properly. Long story short if you need any parts for the hfs6 I have a full kit to part out with.