Base Injector Rate larger, causes RICH condition?

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JohnDee68
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Re: Base Injector Rate larger, causes RICH condition?

Post by JohnDee68 »

immortality wrote:Ignore generic OBD2 codes as they don't apply to the V6 engines which still uses ALDL comms protocols.
:) Thanks guys, I mean no disrespect to anyone in the questions i ask. The way i see it is that we are all here to learn.

With respect immortality, then I would have to question why my purchased software for the Vx v6 that diagnosed the error, then refers to the error as "P0151 = Left side O2 Rich." if the generic codes are not valid ? Or are you meaning the codes aren't actually the same for the ALDL and the software is wrong in what the error it is stating?

I can see as you agree also immortality, that if the fuel pressure is changed significantly from the specs of the manufacturers ratings that there could be altered values of cc/min. Though the differences between item 2 & 3 which both have 3.5Bar as the rated fuel pressure needed, give very different values of nearly 70cc/min and 7.19 lbs/hr more fuel being injected in to the cylinder. Item 1 & 2 are 3.0 and 3.5 Bar with only 0.2cc/min variant. So I don't see there being a significance to the pressures there.

From previous bench testing of injectors some time ago, fuel pressure around the 35-45psi didn't even make anywhere the significant changes to volume output like items 2 & 3 state. With the difference of 7.5 psi between the 3 and 3.5Bar, I would suggest that it too wouldn't matter to the specs given by the manufacturer. Fuel types could though, given that Bosch state themselves they don't use petrol when they test the injectors for getting the specs they state. but that would be also minimal I would think.

delcowzzid, I respect all on here and who have done the work and I acknowledge that there would be very many hours and many people dedicated and working to have got these things to where the values are. But it seems they may have based the values on that which aren't the same as the ones from Bosch themselves state. I am yet to bench test my injectors for their actual specs, but all currently fitted are genuine Bosch ones and of the same labeled part number. I am suspecting that there are going to be differences in them but unlikely to an amount of around 70cc/min.
I tried the china ones a few years back and had 2 of 6 fail for various reasons on install, so they all got thrown out at the same time. A learning curve with a cost.
The1 wrote:Holden did use the same base injector rate between VS - VY. though the injectors flow different YES. I think it was lazy, because after VS they added the injector rate table, they just tuned that, instead of altering it then tuning it.
The1, so could it be possible then that on some series of the Vx cars they altered the injectors to the 150cc/min and the ECU accordingly to cater for the lower injector flow rates?

At this stage I just can't confirm if the current ones are performing correctly or even with all of equal and identical specs of say 150cc/min or >220cc/min. So in the interim until i make another injector tester, I will ponder the logic of the whole situation.

Thanks guys.I will keep you all posted as I find more results.
immortality
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Re: Base Injector Rate larger, causes RICH condition?

Post by immortality »

What software are you using? We generally only use either Tunerpro or software from Envyous customs (Tazzi on this forum).
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The1
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Re: Base Injector Rate larger, causes RICH condition?

Post by The1 »

All models use same base injector rate in tune.

You won't know anything about your injectors unless there flow tested and checked.
JohnDee68
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Re: Base Injector Rate larger, causes RICH condition?

Post by JohnDee68 »

immortality wrote:What software are you using? We generally only use either Tunerpro or software from Envyous customs (Tazzi on this forum).
Yep, they are the only two software I am using.
JohnDee68
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cars: L36 Vx Series 2 8/2002 Acclaim Wagon 3.8L ECOTEC II.
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Re: Base Injector Rate larger, causes RICH condition?

Post by JohnDee68 »

The1 wrote:All models use same base injector rate in tune.

You won't know anything about your injectors unless there flow tested and checked.
I presume only when "stock" injectors are used ?
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Re: Base Injector Rate larger, causes RICH condition?

Post by Charlescrown »

I'm also curious what software your using because a P code is definitely OBD2 powertrain code which your car isn't unless it's a V8. IT should be a numerical code like 12 system pass. I have always found I have to go a little less than the knijflow calculator number.
JohnDee68
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Re: Base Injector Rate larger, causes RICH condition?

Post by JohnDee68 »

Charlescrown wrote:I'm also curious what software your using because a P code is definitely OBD2 powertrain code which your car isn't unless it's a V8. IT should be a numerical code like 12 system pass. I have always found I have to go a little less than the knijflow calculator number.
I'm using mainly TunerProRt and the diagnosis (fault ) codes I use the Envyous Customs software "Advanced Engine Diagnostics" software with their ALDL cable. Which is what gave me the codes P0131 & P0151

Yes the kinjflow value is a slightly less than the calculated value I needed to use also. as the calculated value was not quite running spot on to my liking at the time.
the calculator gave a figure of 557.13, but after trialing a few varied values around that range, i ended up settling on 550.00 ( I presume this would be from the variants in injectors themselves and in the motor which just needed a little tweaking?

With testing yesterday, I have noticed the idle fuel rate of 1.5L/Hr, which is getting closer to the 1.2 to 1.4 L/Hr it used to do. I did notice that a lower Inj Base Rate increased the L/Hr, which might mean that mine should be more to the 560-570 range, but at this stage 550 is stable and seems without any bad issues. It is a work in progress this tuning, as I am learning as I go along. It is also a slow process having no real time adjustments.
I am also still yet to flow test the injectors to ensure one or more aren't failing or out of greater than 10% variant in flow to other injectors. I am suspecting, just a theory, that when reducing the fuel of all injectors to a minimum of their rated ranges, it would show up if there are any injectors that aren't fully functioning as equal to the majority. But it is a theory at this stage. I will know if it is right once I flow test them all.
Charlescrown
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Re: Base Injector Rate larger, causes RICH condition?

Post by Charlescrown »

Ah so your using the1's enhanced bin. I haven't looked at that so yes there may be some variables you can play with. The important thing I look for with o2 sensors is how active they ere which is a good indicator of their health. I think I told you of the car that went for 2 years chewing fuel, had multiple set's of plugs and leads and never logged a code. It was Dave from CODA that found it was a lazy o2 sensor. He passed the knowledge onto me and I have never forgotten.
JohnDee68
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Re: Base Injector Rate larger, causes RICH condition?

Post by JohnDee68 »

I do recall reading about the "lazy O2 sensor".

I am pretty confident that I don't have any sensor issues with the car. My O2 readings do respond in quite quick times as expected.
People don't believe me when I tell them they are all the same original sensors, some 507,000Km now and still going strong. I am curious as to what the speedometer will do when it gets to the 1,000,000km. "you have to be kidding" being displayed comes to mind :)

Today I played a little with the fine tuning more of the Injector Base Rate to a more precise range. I now have the car idling at 1.4 L/Hr, almost perfect for idle like it used to. There is and has been a little bit of a roughness at times at idle, which I am suspecting it is the variance in injectors. My next two priorities are 1. to do a road test and 2. to build the injector flow testing unit. So then I can see and hopefully confirm injector issues as the cause of the whole fuel and rough idle issues. Then if injectors are shown 100% to be the cause, I may be inclined to treat the car to a belated "20 year birthday gift" and buy a set of new Bosch injectors.

It is strange though that at some point the STFT and LTFT were giving quite negative values which indicates and confirms a rich condition still. Some values were as low as -30's for STFT and about -15 for LTFT. This in my mind is likely to be one or more bad injectors which is likely putting too much fuel into a cylinder from failing.
I am presuming that the ECU needs time to self adjust while driving for the correct fuel trims ? As I have only been doing stationary checks on the engine at this point for periods of around 3-8 min testing logs.
immortality
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Re: Base Injector Rate larger, causes RICH condition?

Post by immortality »

The thing is, you are using the injector flow rate to tune your idle when the reality is you are affecting every facet of the tune that used the base rate injector data.

You might be better off leaving the injector rate constant as it should be and figure out why the fuel usage has changed during certain conditions.

By your own admission you suspect a injector issue, tuning around the issue doesn't solve it. The LTFT and STFT are telling you something is off, your best bet is finding that something and fixing it before you start changing the tune wholesale. Just remember, the tune was fine when you first had the car and you are trying to get back to that. 500,000km is a fair distance and I'm sure some of the bits and pieces on the engine might be tired and need sorting first.
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