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Running Lean


Steve

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Havent used the car much as is stored at my brothers house, whilst i was moving. Still havent got it home yet as too much rubbish in the garage.

 

I took it out for a gentle ride today and noticed that AFR were sitting around the 15.0 area, but to be fair i noticed this before i stored it at my brothers.

 

I hooked up the emanage to make sure the map was still ok, it was still the same as when Ian C mapped it.

 

Even the tickover was going into 16.0's and off the scale, if i adjusted the airflow i could get back too normal (14.5 ish), but why would it change?

 

Could it be a blocked injector causing it to go lean?

 

Whats the best way of checking? Or shall i just remove them and get them tested and cleaned? They are PE650cc's.

 

Today i tried fitting a new fuel filter to see if that helped (needed doing anyway) but its still the same.

 

Any ideas?

 

Thanks

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That sounds odd. You should get it to go noticeably rich at low rpms, like 1500, just by suddenly jamming the throttle wide open, does that still happen?

 

If you can datalog it I can look at the logs and see if anything is obviously wrong.

 

-Ian

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That sounds odd. You should get it to go noticeably rich at low rpms, like 1500, just by suddenly jamming the throttle wide open, does that still happen?

 

If you can datalog it I can look at the logs and see if anything is obviously wrong.

 

-Ian

 

 

Gonna send them accross now :thumbs:

 

 

Edited to add: Sent. Thanks Ian

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Well, you are getting the right duty cycle for the revs and boost you are seeing... Is it smooth or misfiring? Does it feel down on power? Do you get it go rich when you floor it?

 

-Ian

 

 

Seems to hold back when you floor it, then picks up. Does feel down on power.

 

When you floor it in 3rd the AFR's stay around 13 - 14 from memory.

 

Ian, did you see that i had to adjust the tickover airflow from -23 to -11 to get the tickover to stay around 14.3ish?

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Have just pulled the spark plugs out and they are all white, so not enough fuel coming through.

 

I have also noticed that if you turn the ignition on, so the fuel pump is running but without starting it, if you listen by the injectors you can hear the fuel running quite loudly. Have never noticed that before. I would have thought as soon as the pipes are full it would stop flowing untill starting?

 

Could this be a problem with the stock FPR not holding the pressure up and flowing it all back to the tank?

 

Thanks guys.

 

Ian still have the car in bits mate, so cant do another run yet.

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The rushing noise is perfectly normal Steve. The pressure is created by a constant flow force from the pump and a restriction caused by the regulator. The fuel circulates constantly back to the tank (helps keep it cool as well).

 

-Ian

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The rushing noise is perfectly normal Steve. The pressure is created by a constant flow force from the pump and a restriction caused by the regulator. The fuel circulates constantly back to the tank (helps keep it cool as well).

 

-Ian

 

 

Bugger, there goes that idea. :(

 

Do the stock FPR's ever fail though? Not holding pressure?

 

How about a dodgy fuel pump??

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Never heard of one to fail yet. Dodgy fuel pump is dubious, it should manifest itself as a failure to run the engine at all or a marked dropoff of power at some point in the boost curve. However, as the initial datalog showed the right duty at the right pressure I'm not sure what else it could be...

 

I've emailed you a step-by-step testing & logging guide I want you to do for me once it's back in one piece :) That'll help me work out what's going wrong :)

 

-Ian

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Never heard of one to fail yet. Dodgy fuel pump is dubious, it should manifest itself as a failure to run the engine at all or a marked dropoff of power at some point in the boost curve. However, as the initial datalog showed the right duty at the right pressure I'm not sure what else it could be...

 

I've emailed you a step-by-step testing & logging guide I want you to do for me once it's back in one piece :) That'll help me work out what's going wrong :)

 

-Ian

 

 

Thanks mate, just dont wanna run it too long with AFR's like that. But will give it a bash tomorrow, havent got my laptop on me at the minute.

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Yeah, but i was thinking to eliminate Fuel pump problems, also, do a test on the FPR. They can go weak over time. Though as your emanage, could well be something in the setup. Im sure Ian will find it if there is.

I would also consider removing the injector clips and giving them a clean - But you should be able to eliminate a dodgey injector as the engine will be lumpy at tickover (firing on 5 instead of 6 cyls)

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May just try fitting a Aeromotive then as was gonna fit it when i go single.

 

With the emanage, i have checked the files and they are the same as they have always been.

 

Have already checked and cleaned all the injector clips.

 

Thanks for your input, if you think of anything else please let me know. :thumbs:

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