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The mkiv Supra Owners Club

Boost issues - AEM


Pig

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Hi all,

 

I have been trying to up my boost a little through the AEM following a re-wire of the fuel pump (Only want to run 1.6 bar until I am in a position to DATA LOG).

 

The AEM has a Fuel cut load limit of 21.64 psi which I increased to 25.94 and now the thing is boosting through the roof and then settling back down later on in the rev range.

 

I turned the boost controller down to 0 in Manual mode but this didn't change anything and then 1.2 bar in Auto mode.

 

The boost flies up to 1.6 - 1.7 bar and then drops down to 1.4.

 

I would understand if I had changed the WG duty cycle but I haven't so I don't get it!

 

On a side note, the AFR's at 1.7 bar are reaching the high 11's - What is considered acceptable in order to avoid a nice melted mush of metal?

 

Anyone able to offer assistance as I cannot leave it like this as there is not enough fuel for 1.7+ bar (according to the AFR's)

 

P.S - Going to have something to eat, then put back to the way it was an test but as my laptop battery doesn't work this is a very time consuming exercise to change anything!

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11.2 is what you should have but 11.5 being the total limit if you have knock detection, i would say what ever you have touched put back to how it was and test again, the psi on the AEM is psia which is the atmosphere preasure and then your boost on top,

Does sound like a boost control issue so could be a split vac pipe or too much duty or gain

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Thanks, was mapped but pulled back for safety as the pump wasn't keeping up.

As a result I was recommended to install a large cable direct from the battery to ensure the pump would have enough power.

 

I was hoping it would be ok but it's not so I the next step is to learn how to add some more fuel and about timing. Unfortunately I just can't get time off work to map so it's down to little old me to learn.

 

I think I have a prob with my fuel pump though - see vid (was about to out another post up about it)

 

http://www.youtube.com/watch?v=z_qkpjLA7OY

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I would agree that does not sound like stable pump flow, I would first check with a meter what voltage the pump is getting , have you bye passed the fuel pump ecu?

 

Using yhe software for addimg and taking timing Is easy but knowing if your getting det needs good ears with a clean det can system , I made one but was picking up wind and all sorts, the rule of thumb is ment to be 1 dec timiing to 2psi iirc

Edited by mellonman (see edit history)
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I would agree that does not sound like stable pump flow, I would first check with a meter what voltage the pump is getting , have you bye passed the fuel pump ecu?

 

Using yhe software for addimg and taking timing Is easy but knowing if your getting det needs good ears with a clean det can system , I made one but was picking up wind and all sorts, the rule of thumb is ment to be 1 dec timiing to 2psi iirc

 

Thanks, I may PM you for some help (once I have bought some det cans).

 

I will check the pump reading at some point. Yes the ECU is bypassed.

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