Hondata

KPro Serial #: 2068-502321
ECU PN: 37820-PRB-A05
Kmanager Version: 3.03
CAL: Post #2
Datalogs: Post #5
Car: 93 Honda Civic Ex
Motor: K20A2
Mods: Hybrid Harness, Hondata 4 Bar Map Sensor, DW 800cc Injectors, JRSC (11 Psi)


Last friday (4 days ago) I had my car tuned at Abel Racing. He used a shelf map from Kmanager and pulled a bunch of fuel out because it was pretty rich. (10.8s-11.0s AFR's) When I left there the car ran amazing (300hp), AFR's were smooth across the board going into and out of boost under light throttle and wot. Well 2 days later the car started doing something strange. As soon as I make 1 pound of boost or less it pegs out 10.0s and pretty much goes limp. In vacuum the car is still smooth as ever, its just now when I cross the vacuum/boost line that it instantly pegs out 10.0s.

Now I've tried a few things, checked all my connections, new ngk iridium spark plugs (old plugs looked good still), compression test (169-170 across the board), TPS is reading, swapped to my stock map sensor from your 4 bar (still no change, swapped back), disabled the IACV, checked for vacuum leaks, and installed my primary o2 (Denso 234-9005) to go closed loop and nothing has worked. My UEGO and Primary o2 sensor read exactly the same. I do not have a single check engine light. Only when I try to force it a little in boost do I get knock. I can not go wot at all my CEL goes solid.

Right now I cant upload my Kal or Datalog. My internet also decided to die at the house. lol Any direction rt now is greatly apreciated!

Heres my Calibration. Working on getting a datalog.

Have you contacted the tuner or taken the car back to them?

I did leave him a message. I live 400 miles away. I don't believe its the tune.

I completed a few logs. Idle, Cruising in 6th, 2- 3rd Gear Pulls w/Abel Tuned Map, and 1-3rd gear pull with the 9PSI JRSC KManager Map.

With the KManager map, I still got knock and super rich AFR's where as before, the map was really lean with running 11psi. My UEGO Wideband said 10.0s, and the primary o2 said 10.9-11.0s. Does the factory wideband not read below that? Just wondering because at idle, my uego and the factory wideband read exactly the same and I thought I read somewhere that the factory wideband wouldnt read below XX.XX.

Anywho, at idle the car feels like it has a miss with both OTS map and my Abel Racing map.

Factory wideband generally does not read below 11:1. The only vehicle fault I see is that there is a problem with the alternator or alternator wiring. According to the factory wideband the vehicle is running quite lean at cruise, and the MAP is fairly high for that speed, which may indicate the actual AF is something else (air leak in exhaust?). Otherwise the injector duration looks about right, and the fuel tables seem ok. In the past this type of problem has been caused by other factors, like the fuel pressure regulator and fuel injectors. I'd fix the alternator wiring and then start to look at the fuel system.

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Hondata

Where did you find the fault for the alternator wiring within the datalog? Just wondering so I know where to look.

As far as any exhaust leaks, there isnt any. I have a ws2, fairly restrictive so I would be able to easily hear it.

My injectors are brand new, doesnt mean they arent acting up. But looking at the duty cyles, they are exactly where they were after leaving the dyno. The tuner told me what they were because he was surprised how much fuel he had to pull out on my methanol tune. I will look into the fuel pressure regulator. I know at idle, it is rock solid at 43 psi. Would it be a good idea to have someone look while using the 2 step as I would have to run a gauge inside the car if not? I hold 10 psi on a 4250 2 step.

Also as far as the alternator, I did notice the voltage drop from the 14 volt column to the 12/13 volt column.

Thank you so much for your insight, Ill check back in with further datalogs and info as I try to figure this out!

Brett

I looked at the fuel pressure on the 2 step, held rock solid @ 43lbs. Regardless, tonight Im going to route the gauge into the cabin to see what it does under load.

Also load tested the battery. It passed. On the battery I'm getting 14.3 volts. On the alternator I'm getting 14.5. On the KManager Im seeing the fluxuation of 13.30-14.30. So tonight I will also be pulling that harness and ohm'ing it out.

Hondata, checked the fuel pressure under full load. It holds 43 psi solid the whole time. Lost in the sauce again. Going to look at the alternator wiring later tonight. Everything was tight on the alternator when I checked it earlier but Ill trace everything back to the ecu.

I ohm'd the main wire from the alternator to the fuse box. It was .4 ohms. I then ohm'd the 3 wires that go from the alternator green connector to the ecu. Each one was between .1-.2 ohms. So in conclusion the harness is good. I also did a voltage check on the cable from the alternator to the fuse box while the car was running and the voltage drop was .2 from 14.5 to 14.3 at the fuse box.

This is where it gets interesting. I unplugged the relay on the hybrid harness not knowing what it was and the battery voltage in kmanager went from reading a fluctuation of 12.6-14.1 to holding solid at 14.1 but throwing a code for ELD and an o2 sensor code. Then I look and found out that the relay was for the o2 sensor on hybrids website. I tested the relay and even tried a new relay but still have the 12.6-14.1 fluctuation in kmanager when its connected.

So I went out and did 2 datalogs. Both of them are 3rd gear pulls. The first one is with the relay unplugged, no fluctuation, and closed loop disabled. The 2nd one is relay plugged in, closed loop enabled and still voltage fluctuation.

So is my board screwed in my ecu?? I have no clue what else to look for. And my fuel system is working just fine.

Both datalogs show a problem with the alternator / wiring / grounding / battery voltage. This is fairly common with engine swaps. The battery voltage should be fairly steady between 13.3 and 13.8V, rising as it gets colder.

You can't measure the DC resistance of the wiring with enough accuracy to test if the wires themselves are ok. For example, calculate the voltage drop over the alternator wire if the wiring resistance is 0.4 ohms and the alternator is putting out 30 amps. You can use a multimeter to measure voltage drop from the alternator stud or battery negative with the engine running, but you'd need to get the voltage steady first. This all may or may not be related to your tuning, but it should be fixed anyhow.

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Hondata

I am an electrician by trade. Reading the continuity of a circuit is pretty accurate when isolated. I understand what you are saying about amperage capacity but there is no drop in amperage using my clamp on at the alternator, or the fuse box with the engine running.

Where are you seeing these faults other than the voltage fluctuation in the datalog so I know where to look and wether or not I have fixed the problem?

Why would the o2 sensor relay cause the voltage fluctuation to stop when unplugged?

Voltage is steady with a slight drop at the fuse box. So obiously thats not the problem. Where should I look next? My engine is grounded in several spots. And my injector harness is grounded where it explains to ground it on the valve cover in the hondata help section. Is there a ground on the ecu I need to look at?

And I would like to add, the voltage is steady at the battery, fuse box, and alternator regardless wether the o2 relay is plugged in or not. Thats why I feel it may be a problem with kpro. If you know of some other places I should look for the voltage drop (where kpro gets its voltage input) Ill be more than happy to trace that circuit!

http://www.k20a.org/forum/showthread.ph ... ost1326263

Bingo....

s far as it being rich, going back to see my tuner next week.