Hondata

I had my Hondata S300 installed by a Hondata dealer with base map on it. 1997 Honda Prelude (h22a) 550cc RC injectors, Stock MAP sensor.

In SManager the low speed fuel table values are being read in column 12 & 13 only. The map never hits column 1 through 11. What could be causing this scenario?

From what I understand the map needs to read left to right based on engine load and top to down as RPM increase. RPM part works fine but load part seems to be stuck on column 13.

I also have a 4-bar map sensor. Is there some calculation or parameters I need to set beside selecting 4-bar map sensor under parameters?

- serial (24649)
- vehicle: 1997 Honda Prelude with H22a swap
- p28 with s300
- 550cc RC injectors, 4-bar ebay MAP sensor, Turbonetics turbo kit.
- Car was starting fine but the fuel load would only read on column 13. I installed the 4-bar map sensor and the car started fine. Today when I went to start it sounds like its trying to start but never starts. The fuel values no longer read in 300 or so they are in two digits so not sure how that changed.

I could not get a good datalog since I couldn't get it to start.

Your MAP sensor voltage is stuck at 5V.

Hondata wrote:Your MAP sensor voltage is stuck at 5V.

How can I correct this? Does it need to be calibrated or something? I was getting the same thing with stock MAP sensor where ECU would only read on column 13.

It is either the MAP sensor, the ECU or the vehicle wiring.

You've switched map sensors so it doesn't sound like the MAP sensor.

Hondata wrote:It is either the MAP sensor, the ECU or the vehicle wiring.

You've switched map sensors so it doesn't sound like the MAP sensor.

This car was originally Auto so I converted it to manual. What should I check for when checking wiring?

I don't have access to another ECU to check so I hate to buy one and find out my ECU is fine.

Another symptom I am having is, if car sits for a while the fuel pump doesn't prime next time. I have to turn the switch on and just sit there for it to kick in after half a minute or so then it would start.

So MAP sensor and fuel pump not priming is two weird things happening.

Also, should the car start if I unplug the MAP sensor?

It sounds like you have multiple problems on this car. Start by trying your ECU in a known working vehicle, If it reads the MAP sensor then you know it is your wiring in your vehicle that is the cause of that issue. The fact that your pump will nut prime unless the key is left in the on position for a while indicates you have either a dying ECU, bad socketign of the ECU , or other faulty wiring or a bad main relay inside the vehicle.

Spunkster wrote:It sounds like you have multiple problems on this car. Start by trying your ECU in a known working vehicle, If it reads the MAP sensor then you know it is your wiring in your vehicle that is the cause of that issue. The fact that your pump will nut prime unless the key is left in the on position for a while indicates you have either a dying ECU, bad socketign of the ECU , or other faulty wiring or a bad main relay inside the vehicle.

After swapping the ECU, the fuel pump is priming now and the car started after adjusting the fuel tables. Rerouted the MAP sensor signal wire into the pin D17 on the OBD1 ECU.

I was able to tune the map to the point where its derivable. Would you be able to look at my calibration and datalog and help me with stall issue and high boost bucking issue.

Please see the attached files. I did the datalog coming to work so you will see a lot of normal driving and then towards the end you will see some 4th and 5th gear pulls where car would really buck and hesitate.

When I start the car AFR is usually rich and when its warmed up it goes towards leaner side when idling at the same cells (Fast Idle Valce has been deleted) IACV is still present. It also starts stalling after its warmed up and driving. If I downshift into each gear then it doesn't stall. But if I was cruising in 5th and came to a light and held the clutch in it would stall.

My wideband is grounded on the ECU but it seems to read slower than what SManager shows. SManager would show value in 10 for miliseconds but my gauge would never hit that value on its own display.

I think I just need expert advice on what to further change in my MAP.

- serial (24649)
- vehicle: 1997 Honda Prelude with H22a swap
- p28 with s300
- 550cc RC injectors, 4-bar ebay MAP sensor, Turbonetics turbo kit, Fast IACV delete.

There is a problem with the MAP sensor. It should not read 75 kPa at idle. I would not drive the vehicle (especially in boost) until you have resolved this issue. The short term trims are going from full rich to full lean. Swap back to the stock MAP sensor and check it reads 100 kPa with key on and engine off. At idle it should be around 30 kPa when hot. If that looks good then switch to the 4 bar and re-test.

Hondata wrote:There is a problem with the MAP sensor. It should not read 75 kPa at idle. I would not drive the vehicle (especially in boost) until you have resolved this issue. The short term trims are going from full rich to full lean. Swap back to the stock MAP sensor and check it reads 100 kPa with key on and engine off. At idle it should be around 30 kPa when hot. If that looks good then switch to the 4 bar and re-test.

This was an eBay 4-bar Map sensor and the description says it needs to be calibrated professionally to be used. In SManager I picked Hondata 4-bar as a Map sensor option and I am thinking that might be the issue? What values should I pick for this eBay 4-Bar Map sensor?

I will try what you have suggested as well by swapping to stock MAP. How much boost a Stock MAP can see?

Another question I had was whenever there is an error code in SManager I don't see my CEL come on in the dash.

You will have to contact the manufacturer of the sensor for it's calibraiton data.

Does the Check engine light come on at all when you turn the key to the on position?

Spunkster wrote:You will have to contact the manufacturer of the sensor for it's calibraiton data.

Does the Check engine light come on at all when you turn the key to the on position?

No Check Engine light does not come on when I turn the key.

Hondata wrote:There is a problem with the MAP sensor. It should not read 75 kPa at idle. I would not drive the vehicle (especially in boost) until you have resolved this issue. The short term trims are going from full rich to full lean. Swap back to the stock MAP sensor and check it reads 100 kPa with key on and engine off. At idle it should be around 30 kPa when hot. If that looks good then switch to the 4 bar and re-test.

Swapped the MAP sensor to stock one and it read 97.5 Kpa at ignition switch ON. When started it read around 34-40 kpa depending on idle.

Could you please check the attached calibration and Datalog and suggest changes.