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Hi all,

My ride : ES 1
engine modal : D17A9

I encountered a problem which surfaced after I have changed my pistons.
Error Code : P0401 Exhaust Gas Recirculation (EGR) Insufficient Flow

Orginal specs : Compression ratio :9.90:1
Bore : 75mm

piston swapped : Compression ratio : 8.80:1
Bore : 75.5mm

Stock gaskets


After putting in these pistons, the check engine light would lite and not go off. I realised that the ECU will detect a 2 cycle warning before lighting up.

Anyway, I could not solve the CEL issue.
even after cleaning the throttle body, EGR valve (New set), EGR passage way this problem still persists.

I have also tried blocking the EGR valve passage with an addtional 1mm gasket.(in attempt to allow the EGR valve to "lift" higher to compensate the compression lost. FAIL

Tried using a bigger bore EGR valve - FAIL

Can anyone who has experience with this error code or CEL issue advise me?
I believe many guys ard have changed to a lower compression piston.Wonder if you have encountered this same problem???

Appreciate all inputs!!!

Cheers!!!


Thanks !!!

 
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are you sure its a D17A9?

 
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Yeah, that's the Euro version of the D17A2. Same bottom end, slightly smaller valves on the head to give it better emissions specs.

As far as your error code goes though, probably the only way to fix is a standalone, unless you're good with electronics. You would have to simulate the stock EGR signal that the sensor sends in order to ditch the CEL without going to a standalone. To do that though, you'd have to figure what the stock voltage is that it would send and get some kind of potentiometer to add voltage to the signal - basically really complicated - in order to simulate it.

 
Rep Power: 313

what code it P0401?

why did you swap out the pistons?

 
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Yes its a D17A9. I am residing in Singapore. I am going to try the standalone (Honda Kpro). Currently I am using Emanage but this piggyback does not have the function to solve this issue.Hopefully by changing to the Kpro would help solve this problem.

Thank you Speefoos for your explanation.However, its really too complicated Haha.Appreciate your valuable information.Maybe I will try with the Kpro and hope that everything goes well.

Initially, I wanted to swap the pistons together with the con-rods however, my rods got delayed and since my engine was already stripped and because of the time constrain I had to do without the rods.

I believe there are many D17s around that have swapped the pistons to a lower compression.was wondering whether anyone had the same issue as me?If not, what standalone ECUs or piggyback that is used?

Hope to hear from you guys soon.

Cheers!!!