WLAURENT

Any updates on this?

I drove to a Honda dealership from the Dragon meet on Saturday to try and sort out my problems.

My fuel trim goes very rich at idle and low RPM, but the O2 sensor is apparently functioning properly (dealer diag/OBD machine noted that the fuel trim did not match what the O2 sensor was providing as an input).

They were nice enough to pull the injectors and coils from a used car for me to try out - neither fixed the problem.

So summary:

Not the MAP
Not the O2
Not the coils
Not the sparkplugs
Not the injectors

Both the tech at the Honda dealership in Alcoa, TN and my hometown (Phoenix) tech think it may be the PCM/ECU.

For now I am running with the O2 sensor disconnected and the PCM running open loop - runs better but the car does not want to idle.

millertown15

^Did you disconnect the upstream O2 sensor?


Im having the same problem here... Im gonna try and swap computers with a buddy n see if that helps....

WLAURENT

I disconnected the primary (one in the header) - the secondary (in the catconv is purely emmisions related and should not effect performance - just shows that the cat is working).

Another thing I noticed is that some other car functions have changed. When I used to hit the cruise button it would pretty much lockin right at the traveling speed - now it jumps 1-2 MPH and locks there. When I hit resume it used to speed right up to the cruise set-point (for example it would take a couple seconds to get from 70 to 80), now it slowly creeps up to the set-point over a 6-10 seconds to get from 70 to 80 once you hit the resume button (and sometimes it stops 1-2 MPH short).

I measured the voltages going to the PCM and it is dead nuts with what is showing on the battery (both with and without the engine running: 12.99 and 14.2).

I also measured the idle droop/drop voltage and just when it is about to stall the voltage is still around 13.5 VDC - negating the "voltage is dropping to low" concept.

solardodgesrt4

I know that someone checked their fuel pump but maybe the same symptoms could be different problems on these different cars. I would check the fuel pump, or if there is a fuel filter on these cars.

WLAURENT

Already done - fuel pressure is spot on.

The filter is actually a sock in the tank around the pump (pickup?)

millertown15

^ My car does this as well with the cruise... haha just thought it was me. Im gonna unplug the sensors and drive it for a day and see what that gets me. I have tried:

Re-Setting Valves
New Fuel Pump and Filter ( Filter is on the end of the pump )
Map Wack
New Map Sensor
New Plugs
Cleaned Air Idle Control Valve
Seafoam Intake...

Hopefully we can finally get to the bottom of this problem..... Looks like we are finally heading in the right direction.

millertown15

Does the car run better with the O2 sensors disconnected? No sputtering or stalling?

Hey man you said you were in Jackson Mississippi, you live there or just passing through? I live close to there just wondering

CourageOO7

WLaurant, my car is CTSC'd and I have the exact same symptoms. It seems the MAP Whack works temporarily but not for very long. I suspect the only real solution is going to be to install and tune my AEM EMS. Unfortunately, you can kiss emissions goodbye with that one. I am going to see if I can dig someone up in my area who is supercharged and running the EMS.

Best,

Jorge

WLAURENT

I was in Jackson this morning, now I am in Las Cruces, New Mexico. I was over on the right coast for the wake the dragon meet - will be back in Phoenix tomorrow afternoon.

The car ran better without the O2 sensor connected, but it would not idle.

Jorge, does yours have all the same issues? I think it is the ECU/PCM. I will be going K-Pro once it is available - but I need to make sure it is the ECU and not something else first.

Everyone having this problem should post the serial number of their ECU - I am betting something will be apparent.

CourageOO7

Yes, all the same symptoms. I'm in agreement, I think it's something to do with the ecu. I will get the serial # of mine and post up...