197: Fuel pressure measurement help

Antti O

Gold Member
Hello
I am wondering if you can help me. Can you describe how to measure fuel pressure from clio 197?
How much standard fuel pressure should be, PSI or BAR?
Reason because my car have LTFT1 (long term fuel trim bank1) 23%.
It is too much and i would like to first measure fuel pressure if it is too low and ecu needs to add injection pulse time for correct mixture.

All help appreciated.
 
I would check the lambda sensors what I have found is that for some reason the second lambda gets stuck at a fixed reading and with the Renault clip I triggered a catalytic convert test where the car runs for about 3 minutes at 2,500RPM ( regeneration) and seems to trigger the second lambda back to life with varying readings. It had happened on my car I put it down to a faulty battery and av4625 came round and his car was the same before he went for EFI mapping. It seems like if there has been a power loss or failure at an unexpected time and with keyless entry it's hard to get the car in a powered down mode the injection computer gets into a fixed fueling mode without warnings someone on here might be able to help here if they know. I am seeing MPG figure falling at the moment and will check mine again.
 
I know there is a method to turn on the fuel pump for fuel pressure test by shorting two pins I will see but my experience with racing is that there is fuel pressure and fuel flow Litre per minute you might even have an injector that might be not performing well because the car has been unused for so long.
 
After cat lambda is working. It goes slowly between 0.6 and 0.7. Much slower of course compated to precat lambda.
I have been thinking if i can find Mot. 1311-08 Connector, i can measure my fuel pressure with universal fuel pressure meter?
Unfortunately those instructions would not tell what is the reference fuel pressure?

Yesterday LTFT1 trim was mad 32,81%..
Strange car works fine and drives fine. No CEL / fault codes.


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I think it was 3 - 3.5bar I will check the notes when we race bikes the rule check is the fuel pressure and it is 3 bar.
 
Yeah.. thanks!
My friend told that most of the universal car shops do have fittings for Renault fuel rail to test pressure.
I will ask tomorrow if they will do the measurement for me, cannot be that expensive.
 
Has your car got a fuel filter the UK cars don't but European cars can have filters could be an easy place to check fuel pressure. I think it would be easier/cheaper to get the injectors tested if one is not working correctly there maybe no warning lights and the lambda measures all 4 cylinders and changes fueling on all four injectors.
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But your car knows it's too rich and is in the process of reducing fuel which will bring down the Long term fuel trim. your second lambda is frozen with the clip you see a number 425 - 450 and yours looks the same 0.6 - 0.7 volts you seem to be having the same problem as us and the catalytic converter test will give you second lambda readings the same as the first one.
 
about £50 - £60 if you go straight for the Bosch one both lambda's are the same it is just the length of the cable if the cable will reach then you could swap them but yours is a European model I am not sure if they are the same. I will check my car tomorrow and see if I can help in any way you might want to check the connector on the Lambda's there are two types what I call square or oval.
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