K Pro/narrowband closed loop issues

[Dan Page]

Hi all

I've been using K pro for three years now in my k swapped EG running in open loop. The cars always been a little jerky in part throttle and I'm trying to eliminate it. I've changed TPS for a hall sensor which works perfectly now. I'm going to get it tuned but my tuner advises me to wire up my narrowband sensor and it'll make it much smoother in daily driving. I've been trying to do this for three days! But I think i'm almost there. Problem is my tuner (who I don't want to take it too until I know everything is right as he's 200 miles away) has said my short trim seems too high of a percentage and there must be a problem?

I've uploaded a .kdl datalog from this morning.

Spec is:

Factory spec EU EP3 .kal with multiplexer, ELD, second o2 disabled (basically the standard map which is built in K Manager)
PRA ECU with K Pro
UKDM K20A2 EP3 engine
Hybrid harness
Hybrid Header
RBC inlet manifold
K Tuned 3" with velocity stack
3" exhaust system
Walbro 255 fuel pump
50 psi fuel pressure
Brand new NTK narrowband sensor OZA563-H5

Any help at all would be massively appreciated.

Thank you

Dan

The car in question:

[Hondata]

'Gear Comp' -> 'Tip in retard gear multiplier' -> set all values to -100%

Adjust the TPS under 'Knock/TPS' -> 'Scale TPS'

Ignition timing looks very low (22 degrees at WOT)

The short term trim is massive - either the o2 is not correctly wired, the o2 is the wrong one or the car is running very rich.

For the cost of a wideband ($160) I would add a wideband as well.

[Dan Page]

Thank you for the reply Hondata.

I had a wire the wrong way round! I've just fixed that now and I'm now showing voltage in primary o2 :D

However. I'm still getting the error code P0131 after driving for a short time.

I'm almost there I think?

I've attached a new datalog to show this.

Trouble is I'm on a UKDM PRA ecu which doesn't accept wideband so I have to use narrowband unless I change my ecu?

My o2 sensor is definitely the correct one as there was no other type showing for a UK EP3. In fact my friend has a stock EP3 who also had o2 troubles and we bought the same for his car with no issues.

Thanks

Dan

[Spunkster]

You should get an aftermarket wideband instead and wire it into the ELD input.

If you wired it incorrectly you may have either damaged the o2 sensor or the ECU. Try the ECU in a known working car and see if it reads correctly. You could also swap the sensor into a working car to see if it reads correctly.

[Dan Page]

OK I've had a bit of a break through.

The sensor seems to be working OK but the S trim value doesn't increase and decrease like how I'd expect it too. It just creeps up to 46% then at 46% it puts the CEL on and stops working.

Doesn't matter how you drive, on or off throttle the S trim just creeps up to 46% then bang, error code and the whole o2 stops working.

Any ideas?

Thanks

Dan

[Dan Page]

I can't use wideband though as my ECU is UKDM PRA? Which'll only read narrowband right? Or is wiring it into the ELD input a completely different way of doing it?

My brother has a EP3 so I'll try as you've suggested tomorrow.

Thanks for the reply mate :)

You should get an aftermarket wideband instead and wire it into the ELD input.

If you wired it incorrectly you may have either damaged the o2 sensor or the ECU. Try the ECU in a known working car and see if it reads correctly. You could also swap the sensor into a working car to see if it reads correctly.

[Spunkster]

You can use an aftermarket wideband such as one from PLX Devices and input it on the ELD input. It cannot be used for closed loop unless you used the simulated narrowband output from it.

[Dan Page]

**UPDATE**

Tried my K Pro in my brothers EP3. Working fine.

Tried my o2 sensor in my brothers EP3 with my K Pro. Working fine.

So I thought it must be a wiring issue on my car. Re-made all connections. Same problem!!

However, I'm starting to wonder is the sensor far enough into the exhaust flow? I had to have the sensor thread welded in to take it and maybe it's too deep of a thread so the sensor isn't getting a good enough reading?

I've attached a pic:



Thanks

Dan

[Spunkster]

That bung may be part of the problem.

[Dan Page]

Sorted!! It's finally working :D :D :D

I've attached my data log.

It was the bung. I got my welding guy to replace it with a much shorter one and it's all working fine now with no errors at all and trimming perfectly.

Thanks for the help people :)

Dan

That bung may be part of the problem.

[Hondata]

Glad it is sorted out and thanks for posting the solution to the problem.

[Wallie7]

Hi , I am new to the whole world of hondata and am currently putting a k20 into a lotus Elise, I am using the engine, gearbox ecu and wiring harness from a 2004 ep3 and am struggling to find any info on retaining the standard primary lambda sensor setup. This PRA ecu has the k-pro 4 inside. Thought I'd ask here, sorry if it's in the wrong place.

[Spunkster]

The PRA ECU cannot use a factory wideband as it does not have the circuitry.

[R-civic]

I wonder if the OP's car is running better in partial throttle.