Edited for new updates...
I have a 98 Civic CX. I have a brand new AEM wideband and Boomslang OBD2A-OBD1 conversion harness. I recently bought a S300 and got a P28 that was already socked for a S200. The ECU worked perfect in my buddy's car when he was running the S200 so I know its good. The pins were modified to work with the S300.
I removed the stock O2 and put in an AEM wideband w/ gauge. The output is going to the stock O2 pin in the ECU. The AEM allows you to set the output to 4 different types. When set to narrowband it works pefect with my stock ECU and the gauge reads correct.
When I start the car with the P28 and S300 hooked up and wideband set to the 0-5V output, the A/F is always 17.66 at 3.81V (my friend said the Honda ECU won't read any higher than that O2 voltage). It idles funny. When I hit the gas, the A/F is 17.66 all over the fuel map. The calibration file I started with was the P28. Even if I add 70% fuel it still has a bogus A/F. Everything else seems to be ok and working correctly. When I change things in the Hondata program it reflects like normal (rev limit, disable features, etc). The only code I am throwing is the IAT because it is not hooked up. I hooked the ouput of the AEM to the ELD and it showed a higher voltage, but the same problem... LEAN all the time.
In the software I have closed loop off and in Settings it is set at O2 sensor and the following:
O2 Voltage - A/F Ratio
0.00 - 10.000
5.00 - 20.000
Calibration file: http://www.rndauto.com/Stock_D16.skl
P28 ECU Problems? HELP!
P28 ECU Problems? HELP!
Last edited by ranta18 on Fri May 05, 2006 11:15 am, edited 3 times in total.
Mike Ranta
First post updated...
Last edited by ranta18 on Fri May 05, 2006 11:10 am, edited 1 time in total.
Mike Ranta
THis is your problem. With the AEM wideband it goes from 0-5 volts. The ECU doesn't know what to do with it. Take it off the O2 out and put it on the ELD wire.ranta18 wrote:I have the AEM output wired into the stock harness where the stock O2 output went. Is this an issue? I also have it set at 0-5V. What do the LED lights on the S300 mean?
I can't look at your file now but can tonight. Do you have it set correctly in the software?
Edit, which AEM wideband is it? The guage type should be fine.
For what its worth, I'm not sure what made you get the AEM gauge but I have used 2 and they are complete junk. Save yourself the trouble and get a PLX. My $.02
It is the gauge type AEM wideband. It works pefectly fine with the stock ECU and the gauge reads correctly.
Last edited by ranta18 on Fri May 05, 2006 11:14 am, edited 2 times in total.
Mike Ranta
First, I need to look at your file to see your settings. I probably won't get to that until Friday. Do you still have the stock O2 hooked up? If so, the ECU doesn't know what to do as you have 2 different volatages going in.ranta18 wrote:It is the gauge type AEM wideband. It works pefectly fine with the stock ECU and the gauge reads correctly. As soon as I hook up the P28 the gauge goes to max lean and the Hondata says 3.85V (my buddy that did the s300 harware install said thats the highest the stock ECU will read). With the AEM gauge you can adjust the output to be 0-5, 0-2, or stock. In the software under settings I have it set at O2 sensor and the following:
O2 Voltage - A/F Ratio
0.00 - 10.000
5.00 - 20.000
What do I do to hook it up to the ELD? If I do that, what do I hook to the stock O2 wire? I only have the AEM O2. I don't understand why the gauge would still read all the way lean. Sorry for the newbie questions.
The ELD is in input on the ECU (Electronic Load Detector). I can't remember off the top of my head which pin it is but you can wire the AEM wideband wire out to this pin wire on the ECU. Then you can easily switch from closed to open loop.
This may help if you haven't seen it.
http://www.hondata.com/techplxwiring.html
Hondata may comment on the AEM gauge more as they use to not work well with the stock ECU either as the voltage isn't linear if I remember right. This is why I (and Hondata) suggest the PLX. They can correct me if I am wrong.
First post updated....
Last edited by ranta18 on Fri May 05, 2006 11:12 am, edited 1 time in total.
Mike Ranta
First post updated...
Last edited by ranta18 on Fri May 05, 2006 11:13 am, edited 1 time in total.
Mike Ranta
You need to set the settings correct for the wideband. This is what you have now.
also change it to Air/Fuel in the Lamda units.
You will need the spec sheet from AEM and probably have to dial the voltage offset once you get it running. Select "Custom" and enter the values from what AEM gave you.
If you are boosting, change the target in boost to 12 as well.
When you say your are not running the stock O2, I assume it isn't even plugged into the harness?
also change it to Air/Fuel in the Lamda units.
You will need the spec sheet from AEM and probably have to dial the voltage offset once you get it running. Select "Custom" and enter the values from what AEM gave you.
If you are boosting, change the target in boost to 12 as well.
When you say your are not running the stock O2, I assume it isn't even plugged into the harness?
First post updated...
Apologies for trying to help. This is becoming very frustrating.
Apologies for trying to help. This is becoming very frustrating.
Last edited by ranta18 on Fri May 05, 2006 11:17 am, edited 1 time in total.
Mike Ranta
When i opened your file. This is what I saw. TO me this means the values aren't showing and would cause a problem like what you are having.ranta18 wrote:That is NOT what I have. Do you even read what I'm posting? I just got done saying TWICE that I have it setup in the S300 correct. I will repeat once again...
In the software under settings I have it set at O2 sensor and the following:
O2 Voltage - A/F Ratio
0.00 - 10.000
5.00 - 20.000
You are on your own for being a prick.