saab 9-3ss bigas lpg

[alextg]

Hello there,
My name is Alexander and I'm from Greece.I took the courage to register to this forum and send this msg as i saw, that people in NL have far more experience in Saab+LPG , rather than here in Greece that they dont have a clue ... You rarely find saab+lpg (even more a tuned saab+lpg)
I have a 2005 9-3 2.0t and recently i put the injectors from aero and the td04-14t turbo and got a remap , and now im at 250hp/370nm.
The thing is , i have a BIGAS LPG system that was installed in 2011.
After the remap , my lpg mechanic installed a double reducer (i had the single) thats rated up to 350hp, but i'm having alot of issues with the car.When you are for example 3d gear and low revs and press the pedal to the floor , the car is having some kind of BIG stutters ... I dont know whats the issue is and i dont know if my LPG mechanic knows aswell. When you drive "normally" the car doesnt have any issues at all ... the issues are when you request HP/Torque from the car and i guess the LPG system cant deliver ...
So , what i wanted to ask is , what kind of LPG system should i get (ECU/injectors) so that i wont have any issues ?
My mechanic told me that my ecu is old so are my injectors (installed as i said in 2011), and im thinking that maybe thats the issue .... Maybe the ecu or injectors cant work with that kind of hp/tq ... I know that my system already runs lpg+petrol when its needed , but still i guess thats not enough.
Thank you all and sorry for writing in english in a dutch forum ...

[Funky Dude]

Hello Alexander,
I'm not an expert on the SAAB 9-3 or LPG but BIGAS is not a current brand overhere. The systems here are mainly from Prins or Vaille and never give LPG and fuel combined, it's fuel or LPG.
If the ECU and injectors are too old, your mechanic should have told and checked this upfront and if they were working fine before the tune-up, I don't see why they wouldn't now.
With Tech-2 you can read the errors, preferably by someone who knows SAABs. (I get the impression your mechanic doesn't)
Good luck!

[Orphy]

Nou nou, dood luck is ook niet echt gastvrij

[alextg]

Hello Alexander,
I'm not an expert on the SAAB 9-3 or LPG but BIGAS is not a current brand overhere. The systems here are mainly from Prins or Vaille and never give LPG and fuel combined, it's fuel or LPG.
If the ECU and injectors are too old, your mechanic should have told and checked this upfront and if they were working fine before the tune-up, I don't see why they wouldn't now.
With Tech-2 you can read the errors, preferably by someone who knows SAABs. (I get the impression your mechanic doesn't)
Dood luck!

Thanks for the reply ... the thing is that when my car runs on only petrol , everything works perfectly ... car responds just fine ... the problem is when the car runs on LPG only ...
As for the LPG or fuel , as far as i know , many systems , when they inject LPG, they inject some little portion of fuel aswell ...

[millerman]

Most LPG systems use the opening times* of the petrol injectors to determine the opening times of the LPG injectors. With some finetuning based on other sensor values. If you changed out your petrol injectors, my best bet is that the basic mapping to control the LPG injectors is still set to the opening times of the old petrol injectors.

An example (these values are not realistic, purely to explain)
In your previous setup, your petrol injectors would open for 0.2s and in that time inject 50cc of fuel. Your new petrol injectors can inject more fuel per second, so in order to deliver the same amount of fuel (50cc) they might only open for 0.15s. Your LPG injectors however think that 0.15s opening time of petrol injectors means your care only requests 35cc of fuel instead of the needed 50cc. Therefor the LPG system will not deliver enough fuel for your car. There are numerous mappings that help finetune for these issues, but the more you rely on these corrections, the less room there is for your Saab to correct for other issues outside the LPG system.

Hopefully this makes sense? The solution would be to get a new mapping for the LPG system. If you rewrite the petrol mappings to fix the LPG system, your car won't run on petrol properly.

*) Note that the ECU doesn't really control the opening times of injectors, but a voltage range that corresponds with the opening time.

[Funky Dude]

As I understand it from reading the other topics on LPG-problems:
- Are the LPG-injectors the right type for the higher performance?
- Is the LPG-regulator adjusted for the tune-up?
An LPG-specialist would be the place to go.

[alextg]

Thanks for the replies ... The thing is , the guy that i went to get the updated reducer , is the guy thats the LPG specialist and setups the BIGAS installations ...
The maps of the petrol were changed obviously when i got my remap, but i dont know what happened with the LPG fuel maps ... He said that he recalibrated the car , tuned it cause of the changes that happened, but i dont know for sure what he did , or i dont know again if the lpg injectors are up to the task for the new power the car has ...
I emailed him and asked him about these stuff , if the lpg-injectors/lpg-ECU can handle the new HP/Trq or if i have to get newer-better ones ...
As soon as i have news , I'll let you know
Thanks again

[gertram]

As for the LPG or fuel , as far as i know , many systems , when they inject LPG, they inject some little portion of fuel aswell ...

I've heard of only one system that does that, Prins, and they've only made that recently.

Like millerman said it looks like the openng times of the LPG injectors should be corrected.

If you feel your LPG specialist is not on top of things you could install a wideband lambda sensor and gauge to give you information about the mixture whilst driving. If the mixture is too lean at higher RPMs you will wreck your engine in no time.
Extra sensor in a welded bung in the exhaust, gauge on your dashboard. Innovate or AEM for example. I have a VEMS system wth Bosch LSU 4.2 sensor, been working well for 5 years.

https://shop.vems.hu/catalog/round-wbo2 ... 37a577d3fc

[odin1899]

As for the LPG or fuel , as far as i know , many systems , when they inject LPG, they inject some little portion of fuel aswell ...

I've heard of only one system that does that, Prins, and they've only made that recently.

At least Vogels can do that as well, for years. I assume the Italian brand Vogels is based on (Landi (Renzo) IIRC) can inject extra petrol together with LPG as well.

[alextg]

[/quote]
At least Vogels can do that as well, for years. I assume the Italian brand Vogels is based on (Landi (Renzo) IIRC) can inject extra petrol together with LPG as well.
[/quote]

My system does that for years aswell ... its called something "LPG enrichment" ... the guy told me that when a car cant operate only on LPG or the car owner wants , they can put to inject petrol aswell ... and thats how the engine is "lubricated" (my system doesnt have an lpg-oil feed or something) ... how much petrol is injected is configured aswell depends on the HP of the car .... then , he told me ,if the HP is even bigger, the newer version of the ECU , can start injecting big amounts of petrols in a whole cylinder ... for example first cylinder is injected with petrol, rest 3 with LPG , then 1lpg,2petrol,3lpg,4lpg etc etc etc ... thats what he told me concerning how ECUs operate etc ....

[Dikketrip]

Whats the state of your LPG installation?

Is your pump still making the right pressure to feed your extra lpg.

And are the old nozzles still working right?
Its from 2011.. that like 7 years of fun.

You tuned your gasoline with bigger aero injectors? is the conversion to lpg also adapted to it? You doubled the lpg input.

May be it needs some fine tuning..


I think prince and vialle can do like 65-70hp per cilinder?
4x 70 = 280hp max

Just need the right ecu and injector pack pump etc.

[Dikketrip]

Your bigas Is vaporizer?
Some like this?


http://www.bigas.it/en/products/lpg-red ... -21-double


Not injector?

[LBJP]

hi,

look in https://www.lpgshop.co.uk/lpg-diagnostic-software/ search for bigas and you will find software to setup your power.

I had a 9-5 2.0t Saab on Bigas, Tuned to 240 Hp.

There is also a parts shop.

good luck