Hondata

If I leave in the default value (790mbar) then the engine operates in open loop from almost 10% throttle and up which I believe is too early. However is it safe to operate the engine in closed loop for loads over 800mbar? I currently have it at 860mbar and seems fine (open loop at around 16% throttle at 3000rpm and 22% at 5000rpm).

In a recent trip, I noticed that the ECU would go in open loop mode after some minutes of driving in the freeway (steady at 4500-5000rpm with 5th gear) whatever the load was. I even pulled over and let the engine idle and it was still in open loop (showing rich). I switched the engine off and then back on and I had closed loop again. AFter some driving the same happened. I've never noticed this in city driving even after 2 hours. What's wrong?

Iassu Chris,

Maybe you have read my thread about cleaning the O2 sensor.
Actually I am in Germany, have a Civic 1,8 VTI too, JRSC and Hondata s200.
I remarked the same things with my ECU. It is almost all the time in open loop, which is healthy for the engine but bad for our gas mileage.
Moreover, you need to watch your catalytic converter (if you have one;-)
If you go too rich it will stop working and in worst case it can melt.
What I think is the reason for that is the different atmospheric pressure which you or me are in.
Should I get definitive reasons I will let you know.
What car are you exactly driving?
Can you let me know your setup?
It's very nice to find another JRSC or Hondata user in Europe.

Best regards,

Andreas

Hi ACE! I have a '95 civic hatch VTi with b16a2 engine (not hybrid). My car as yours was never imported to the US. What ECU are you using? I am using a P30G (stock) with disabled knock sensor and some other stuff and works fine. Air pressure doesn't vary so much. I am almost at sea level.

My car goes off closed in highway driving only and I don't know why. To be honest, I have been only once to a highway since I installed hondata. Mostly city driving with no problems in closed loop operation. What threshold do you use? (I use 830mbar).

MIleage however is very good even with open loop (may be I don't run very rich).

I have the stock cat on my car. Time to replace it with a race one and install a new lambda sensor (may be wideband).

BTW, what do you mean by Iassu Chris?

Hi,

Iassu Chris?
Actually I did a partial mistake her. I was too quick when I read your login here. I somehow read ChrisVTI instead of Civic VTI.
Think I had too much wine yesterday, lol.
And "Iassu" should be known to you if you are from Greece. OK, it is certainly written wrong but you should know what I mean, or not?
So you have a hatch. I suppose it makes 160 hp, exactly like the VTI's here.
I do not know why your car does not work in closed loop on the highway only. Can really see no reason. Either it never goes in closed loop or always. The only thing would be that you do not feel when it is in closed loop because it is there very short time. I am also at a very low altitude and especially when you are at sea level this could have an effect on the threshold between open and closed loop.
Do you have an air/fuel ratiometer?
By using one you can see exactly when you are in open or closed loop.
Also, I see that you use Hondata for a n/a application.
I have a supercharger on my VTI and a fuel map exactly written for my setup.
From factory I had a P72J ECU and I swapped it with a P28 when I went Hondata. The supercharger boosts with 11 psi (0.8 bar) and I also have 440cc injectors. That's all and is good for 240 hp at the wheels and about 260-270 at the crank. That's really great when VTEC engages at 2000 rpm. Enormous power until 8300 rpm.
Jackson Racing supercharger and Hondata was the best thing I could do for my Civic. I paid for everything 5000 Euros.
Should you want to get more of your car you can also drop me an email to ace@jrsc-civic.de

Andreas

It crossed my mind that you mean 'geia sou' by 'iassu' but Chris confused me . I have an AF gauge and this is how I see when the car is in closed loop. I'll have a trip on Friday so I'll see if it is doing it again. I plan to stay NA because I like the way my civic is. Anyway, it's just 1080kg. I may build a CRVtec in the future but for now my engine is pretty strong putting down 162whp with the stock cat on. Too hot here for the supercharger! Have fun my friend, keep in touch.

Geia sou,

(He he, I learnt sth)
Yeah, you are right, it's too damned hot in Greece. Actually I am from Romania and know what you mean.
162 whp is good on a n/a B16A2. Can you tell me about your exact setup? Per mail if you want. I have two friends here, on with a EG6 and another with a EG9, both have same engine as you know.
They do also want to reach 160whp or more. Currently they want to buy a ITR intake, ITR throttle body, June or Spoon cams stage 1 and rise the compression to 11:1. Also they already have headers and are going to put a 63 mm exhaust. They do also already have a race cat. They are quite cheap here. You can get one for 200 Euros with 100 or 200 cells.
I have one with 200 cells.
Would be really cool if you can give some idea what else to do or what you did to make that power.
I do also wish you a Merry XMas and am loooking forward to hearing from you.

Best regards,

Andreas

P.S. One of my friends I spoke of has an own website with some videos.
Check www.eg6.de
There are also some vids of my JRSC Civic but before I had Hondata on it.
After, I made only one vid versus a Opel Calibra with 280 whp on the German highways. We pulled from 50km/h to 200km/h.
http://lightstorm.gmxhome.de/MC2vsEDSCali.AVI
It's quite nice to see a Civic Station Wagon with not bad power.
Here are some pics of my car.
http://hondapower.de/php/memace.php

My mods are not extensive. But they are well combined. I pulled 162whp WITHOUT hondata so I am expecting sth more in the next dyno session. My engine mods are:

CTR cams, 11:1 CR, DC 4-1 header, akimoto short ram with custom heat shield and duct, 55mm cat back exhaust and adjustable intake cam gear. I use Motul 300v 10w-40 and my valve clearances where 0.15mm for the intake and 0.2 for the exhaust.

Also note that my engine has 112.000km on and compression test showed 235 psi at all cylinders !!! But I am really baby sitting it

Merry Christmas

Indeed, the gain compared to the mods is respectable.
Which CTR cams do you have? I suppose the ones from the JDM B series engine. How did you rise your compression? Another head gasket or did you take 5/10 mm of the head?
Also, with that compression which fuel do you have to use? 95 or 98 octane?

Yes I use the JDM CTR cams from the b16b engine. I have milled the head 5/10 and installed a spoon 2ply gasket. Overall 7.5/10 which is close to 11:1 (I think just a little more than 11:1 as 1/10 is not equal to 0.1 rise in compression). I use 100RON fuel which was shortly available here in Greece but I have no problems with 98RON. Haven't used 95 for a while but with hondata I can tune the car to run with 95. Keep in mind that the camhafts play a very important role in how many ron you need. With stock cams I had pinging much easier since the overlap was less and dynamic compression higher. THis is why agressive cams love high CR.

My previous dyno session at 70.000km showed 147whp with 10.7CR, stock cams, intake, 55mm cat back exhaust, custom rom (before hondata), adjustable intake cam gear dialed at +1.5 deg and 15w-50 mobil 1. So I gained 15whp with CTR cams, header, higher compression and lower viscocity oil. Moreover, I could say that high mileage hondas perform better if all subsystems work fine (ignition, fuel delivery etc).

I have the same problem, it seems that the car is in closed loop cruising above 60mph, everything is fine, EGT is about 12-1300, then for no reason she goes into open loop....why is this.

Have any of you figured out the problem?

My problem is different. The car does never go into closed loop. Even at idle. And I have not found the problem yet

is closed loop enabled in the program?

I've never had this problem again and I've been numerous times in a highway. Closed loop works perfectly. Just update the rom editor software. This is supposed to fix some bugs.

According to Jim Helbing, my tuner in who I have 100% confidence, it is enabled. I think the last option will be to datalog and to see if all parameters to get into closed loop are being fulfilled.

Civic VTI, nice to hear from you again.
Yes, Jim sent me a new chip with the new emulator, but still the same prob.
But I am happy that your car runs fine.
Mine doesn't
Spark plug from third cylinder melt, piston melt, head gasket blown.
Therefore I am currently making a full rebuilt with Darton sleeves, CP 9.7:1 pistons, Eagle rods, etc etc.
Yeah, live sucks sometimes....

So sorry for your engine. Forced induction is dangerous. But getting those nice parts you mention and with careful tuning you should be ok. If you still have the problem with closed loop, change the 02 sensor and check all grounding points of the engine and the 02 sensor.