stuck Map sensor reading

[fierolou]

I've got a SOHC turbo in a 1998 civic 5 Speed. When I try to start the car it runs excessively rich to the point that the plugs get fuel fouled . The only way I can keep it running is to open the throttle almost wide open. Even under these conditions it struggles to idle and eventually fuel fouls and stalls.

When I check all the sensor values I find the MAP sensor reading never fluctuate with the engine running or KOEO.

I have checked the following:

Checked continuity from all three lines of the MAP to ECU and found no opens.
Checked for shorts to ground or B+ on the Map harness and found none.
Added additional ground wire from engine block to chassis and chassis to battery NEG. This made no difference.
Overlayed a new harness from Map sensor to ECU (pin to pin) and still no Map sensor readings changed.
Replace HONDATA 4 Bar Map with stock Honda, changed Map parameters and still unable to run properly (with original and overlay harness).
I replace the P28 ECU with a P06 from my other car and was able to get different map readings.

P28 ECU readings:

HONDATA 4 Bar Map KOEO = 44.4"/psi (with supplied base map)
Stock Honda Map KOEO = 44.4"/psi (parameters changed to stock Map)
Both sensors readings are with the original harness and the overlay harness.

P06 ECU readings:

HONDATA 4 Bar Map KOEO = -29.9"/psi (with supplied base map)
Stock Honda map KOEO = -29.9'/psi (permeators changed to stock Map)
Both sensor readings are with the original harness and the overlay harness.

If I attempt to start the car with the P06 ECU it will not start (don't know if I need to change additional parameters)

If I manipulate the Map sensor parameters on the P28 to read -15.7"/psi the engine starts and runs smoothly.


I am at a complete dead end with how to continue this diagnoses. My understanding and ability to navigate the HONDATA is limited. I suspect that the P28 ECU has a defect that is creating my problem.
Is there anything that I may be missing or do not understand that is creating this situation for me? Is there any further testing anyone can suggest I perform?

[Spunkster]

If the P28 is the problem then you should use a different ECU as it sounds like it is damaged. Have you tried the P28 in a different vehicle with the correct calibration for that vehicle?

[fierolou]

Hi Spunkster,

I installed the p28 into a known good vehicle with the correct calibration for the known good vehicle and it did the same thing. Starts and runs excessively rich . The throttle almost wide open for it to stay barely running.

My Tuner/ECU supplier checked the ECU on a simulator and it passes on the Map parameter.

Any input would be appreciated.

[Spunkster]

Post the calibration as well as a datalog of it running showing the issue.

[fierolou]

Please see attached file.

One other thing I did that has made a change is using a different laptop. The car now starts and runs but I still get no Map reading fluctuations when I open the throttle.

Thanks for the help.

[Spunkster]

You have not provided the calibration used to make the datalog.

[fierolou]

Hi spinster

Forgive my ignorance.
What is the calibration that you are asking for?
Is it the MAP parameters?

Thanks

[Spunkster]

It is the file that is responsible for how your car is tuned with all the parameters and fuel and ignition tables.

[fierolou]

Please tell me this is what you need

[Spunkster]

Do not save it as a pdf or rename it, just attach the file directly.

[fierolou]

Once again forgive my ignorance in my posing ability. Is this correct?

[Spunkster]

It sounds like the ECU itself is damaged and should be replaced, since the ECU had the same issue on a different vehicle.

[fierolou]

I am grateful for all your assistance and patience .

Thank You.