Emission compliance and the VG30DETT

[David Walter]

I am trying to get my self built car with the VG30DETT complied under the IM240 here in Australia. It has a very basic tune, and I was quite suprised when first tested it was very close to passing. However, it showed indications that it was not getting good vaporisation of the fuel. Which was quite surprising as the injectors are new, and the engine in good condition. The air fuel ratios are good, but like I said the tune is basic. As the test is ver low in the maps with only up to 12% TPS seen. There are a couple of issues with it, one is that is has a lot of trouble holding idle especially after start up, regardless how much I play with idle and timing settings. I was wondering if sequential injector timing may have something to do with it. It is set at 400degrees BTDC. I thought this might be a little too early noting the injector placement in the VG30DETT. I was wondering if anyone can offer advice for passing the IM240 test with the link ECU and this engine. Attached is a picture of the engine. Thanks Dave

[Steve1436215419]

Nice! looks like a fun car. What ever the rest of it looks like

Are you running speed density or MAF setup? Got VTC intact or plain adjustable intake gears?

What do you need to get a "pass" on? HC or what? Do tell a little about that setup looks intresting.

[Steve1436215419]

A little quick to press "post comment" there...

As you said it is a basic tune. How "basic"? Have you i.e. done your warmup enrichment ? Did you calibrate your timing, MAP (if thats what you run), TPS and so on. What timing and so on...

Tell you what... Post your map and ill take a look at it if you want. (I run the same engine. In its original home though) What ECU btw?

[David Walter]

Thanks for the offer to look at the maps you will see they are included, along with a photo of the rest of the car To give some insight to the car, and more specifically the engine. It is a VG30DETT with auto cams, that retains the vvt, and has only had a freshen up. It utilises MAP and air temp sensors to measure air flow. The injectors are now top feed 550cc. The turbos are GT2530, and are running minimal boost (controlled by the ecu) TPS, MAP, Timing etc have been calibrate and it has had a few runs on the dyno to ensure air/fuel ratios are safe, and timing is adequate. I thought the warm up enrichment was done as a part of the tuning however it suspect it has not been done for the colder days we are now experiencing. (which may explain the repetitive stalls when cold). I have no EGR, and the crank case ventilation system has been changed to include a catch can before venting into the manifold. I am using the G2 ECU. The test needs to pass the IM240 which includes HC, CO and NOx. With the current tune it was close, but miss by an inch - miss by a mile with these tests. Thanks again.

[Steve1436215419]

That DO look like fun

Now i opend the file with the 4.4.3 software version (G4) . so what I am seeing MAY not be the case.

Not that it necesarily matters (if it works it probably dont) But the trigger is set up as 1 tooth pr TDC in stead of nissan 360 opto. Any particular reason for this?

Your wideband input (AN-1) is setup as 0-5V GP instead of WB input. This way i dont think the ecu knows what,say 2v equates to. If you set it up as a WB you get to choose what 0V meens AFR wise and what 5V meens. You could also set the closed loop mode to WB closed loop. Your "Dither voltage" is set to 0.77v. The ECU thinks that this voltage equals 14,7 AFR. This dont make sense wether you got a wideband lambda nor a smallband lambda. (should be more like approx 0,45v for a SB and around 2,5v for a WB) I think this may be the reason for your failed emmisions test.

That said! What lambda setup do you have??

Also in your Target AFR map... Its spanned with RPM over MAP. Good. but here with me the RPM spans from 0 - 983025 RPM. Now this may be cause of my software, dont know. Just check it out.

When i go into Injector test in your map i only get injector 1 and 2. What happend to 3,4,5 and 6? Could be the software again... I also see its run as sequensial injection so only 2 injector outputs doesnt compute.

Your 400-420 injection timing numbers seem fairly high, yes. But this is best set at a dyno. I got my set at 360 in the VTC off sone and 380 in VTC on. HM. On second look i dont see any VTC output set up. Running without it?  If so you are probably loosing some goot power in the midrange. Then again, this may be what your AUX - 5 GP output is used for? The settings certanly looks that way..

About your startup. To me your Warmup map looks good. Dont really see why it wont run right. Look at the wideband numbers while your warming it up and se what it tells you. (But get the WB set up correct first. if thats what you run that is) You could try to play a little with the ECT ignition trim. Ad a few degrees while the engine is cold. What plugs do you run? The engine should only be ran with OEM plugs. Cooler yes, but still OEM. No other plugs really fits theese engines.  Have your tried to manualy adjust the idle air screew?

 

Again! I opend up the map with what MAY be the "wrong" software so what i see may not be the case.

 

[Steve1436215419]

Never mind my VTC Q`s Just re-read your last reply....

[David Walter]

Whilst, it does appear to be a few issues in that you opened it up in a newer/different version of the PCLink. However the points remain in regards to most of the items. I have already made a few changes based on your insight. Especially with the injector timing, I’ll see how it goes on the dyno tomorrow with the mixtures. As for the trigger set up. For some reason it would not work with the Nissans set up and once on the 1 tooth per TDC it was all good. I am not sure about changing the AN set up to WB ext sensor as it is a standard narrow band. And, I though it just needed the AN1 to be turned on and the setting would be address as a part of the closed loop lambda settings. Correct me if I am wrong the dither voltage should be about 0.6V? regardless 0.77 is a bit high, and could explain a few things. The G2 doesn’t have an AFR map, which may explain the RPM range, also the injector test. I’ll try playing with the ignition trim at idle and with ECT. I might have to resort to the old fashion why and get it set with the idle screw. How do my ignition times compare to your maps? I am not sure on the plugs, I am pretty sure they are standard, but I am loathed to start changing parts until I exhaust the tuning aspect. (Change one thing at a time). Thanks for the advice, please keep any further advice coming. I’ll happily post the maps for all once (if) I pass. Oh. And it is a hell of a lot of fun.

[Steve1436215419]

I agree. This certainly IS a hell of a lot of fun. And for you, whom built your own car like that, i can imagine the exitement,

Reading that you got a smallband lamda setup i think you could leave things in that regard alone. Just adjust the diether voltage to get the apropriate AFR. Thats the only thing its looking for anyways when its set up like that. Adjust the fueling with the CL lambda OFF first. Then adjust the diether with the CL lambda ON so that you get the same AFR.

 

You really should consider installing a wideband (or two). Would be really usefull. Not to say easier for you. As tuning your low load cells with 4 cats on the car would prove quit a task. If tuning with a "but mounted" WB. I somewhat assume your tuner replace one of the lambdas with a WB while tuning though?

 

Your timing map looks very simlar to mine. So it shouldnt be far of. (not saying mine is the perfect one either)

Pleace keep me/us updated on this car. would love to se how everything goes.

Btw. Saw you over at the Australian 300zx foum too. Not a big poster there, (im mostly at other forums)  but i check in regulary to see whats going on there. You know, to get a feel for whats going on in the aussie ZX world.

[David Walter]

Well changing the injector timing certainly cleaned up the CO. And, we are starting to get some very good results. But no passes. The fails are now across all three gases. However they are much closer to the mark with a 1.03 HC, a 12.3 HC, and 1.4 NOx. Have tried winding back the timing in the peak zones (under power, where the majority of the NOx is being produced) Noing that the CO, and HC is quite low in the area we might add a little fuel. This is getting so finite, it is crazy, the finest of changes results in massive changes (in percent) in the results. Still open for any insight from anyone. Would running a mix of ethanol help?

[Steve1436215419]

Good to hear you are getting closer.

Did you try fiddeling with the dither voltage? Did you use a wideband? You want the car to ociliate around 14,7 to help your cats do their work. Exsess fuel-exsess air-exsess fuel-exsess air. This to help feed the cats what they need to work.

I have no hands on experience with E85, but i occacionaly hear about people filling a few litres in the tank before testing. So i guess it works.. Dont fill to much though. And dont run it hard.

As David here said! Feel free to chime in with suggestions folks. This forum IS somwhat slow, i must say..

[David Walter]

Oh sorry Ryan, yes you are right it is not a fan belt, but the alternator and power steering pump belt. A bit of a colonial slang slip. It is really not the load that is a major issue, (other than they have entered double that expected in the car) . However, you need the full voltage to ensure that you get a good spark, as a single misfire would result with a failed test for sure. My car is a little twitchy on throttle as it is, and with the twin plate clutch it is a handful for the driving test off the line. I have attached the test results( sorry it was a screen shot of the last tests). And, after a little confusion (and, tears) it has been confirmed that I have to pass the IM240 overall test result for registration. Test results for HC 0.791 (required < 0.6g/km) Graph attached Test result for CO 14.84 (require <10g/km) Graph attached Test result for NO 1.502 (require < 0.502g/km) Graph attached

[David Walter]

Can only post one graph at a time Test result for CO 14.84 (require <10g/km) Graph attached

[David Walter]

Finally Test result for NO 1.502 (require < 0.502g/km) Graph attached

[David Walter]

Justed passed emissions on the tuner's dyno. Result cam up pretty good in the end. Just remembering I had: HC 0.791 (required < 0.6g/km) CO 14.84 (require <10g/km) NO 1.502 (require < 0.502g/km) A couple of faults and a few tweeks with the tune. And, it dropped to Test results for HC 0.493 (required < 0.6g/km) CO 8.955 (require <10g/km) NO 0.741 (require < 1.50g/km) Then, I noted that the ecu was continually trying to decrease the fuel. And, that there were some spikes so we went looking to find some way ward values in the fuel map. Did the retest, and decided to hold it in gear longer for higher RPMs. Test results for HC 0.472 (required < 0.6g/km) CO 2.814 (require <10g/km) NO 0.892 (require < 1.50g/km) Just really pumped at the moment. So there you have it, you can clean these engines up with a link ECU.