jimboy
You have to take the injectors out & send them off for cleaning.
Yes, yes, obviously I have to take them out.... sorry, but my English is not as good as I would like it to be

...
When I said "without removing" I did mean "how much does it cost to have the injectors professionally cleaned without take into account the cost of the removal from the car, because that's a job that I can do myself".....
I hope I've explained myself

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Is it possible that injectors work differently when temperature change?
I'm asking because of the strange sequence I get:
1)I get rough idle engine when I start on petrol
2)After 3/4 second, it switches automatically on CNG, (different injectors, different ECU, etc...), and the engine runs perfectly smooth
3) if I immediately switch back to petrol, the engine runs roughly and it can stop.
4) if I manage to switch back to CNG, after some hesitations, the engine runs smooth again.
5) If I wait 15 seconds keeping the engine running on CNG, when I switch back to petrol, it runs perfectly smooth...
So, it can be the temperature? I think temperature sensors for petrol and CNG are the same... if they were different I would think of some faulty temp sensor.
There is something off with petrol/air mix, because I can smell bad combustion (not really a petrol smell), and, when I insist on roughly engine running on petrol, I can feel hesitations for a while when I run on CNG (like flooded cylinders).....
Do you have any idea/suggestion???
(keeping in mind that on a CNG engine, many problems on the petrol section are caused by the lack of use of the car when running on petrol...)
s130
So, you are suggesting that special petrols are virtually irrelevant in solving my problem (I've just give it a go, because I would like to try some wizardry before I start to spend real money on the car


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OFF - TOPIC - oil engine
I've read your post, and I'm interest because I would like to change the oil on my car real soon;
My specifications are Fiat 9.55535-S2, that can be found on:
CASTROL Magnatec, C3, 5W-40
CASTROL EDGE TITANIUM, 5W-40
ARAL HighTronic, 5W-40
RAVENOL VMO, 5W-40
KAMOKA CAT, C3, 5W-4
and, obviously, Selenia oil.
Fiat specifications 9.55535-S2 ar not really esaustive:
"Qualification for Diesel and gasoline engine, with exhaust treatment system, lubricants, with extended drain. OEM recommended product also meets: ACEA C3-04, MB 229.51 and API: SM/CF".
My cosideration:
T-jet doesn't have any special parts to lubricate, unlike for example multiair engines, they are pretty standard engines.
What do you think for example of Mannol oils?? I have seen one of them that has the same specifications of magnatec C3 (both oils are suitable for a lot of german cars), but Mannol doesn't have fiat specifications.
I suppose that they have to pay for it, so they prefer saving money because fiat is not a german maker.