Engine Opel 1,4 16V NA, 4 cyl, firing order 1342, without modifications (except exhaust, manifold, air filter)
Car using stock coils, stock injectors, stock electronic throttle body Bosch.
ECU SerialNr:15160
- Internal MAP 400kPa (planned conversion to turbo in future)
- appr +1.2V output in free air (103kPa ambient absolute pressure)
- ETC (with bridgeoutput interface)
PROBLEM:
Car was tuned a half year ago, run perfect, without problems, but since one day last week, customer had a problem with start.
After checking all data with PC, i found problem with internal MAP sensor.
MAP still show 5-10kPa even if the hose is disconnected from intake. I also try to make little over/under pressure with mouth, but MAP value did not change.
This is a screenshot of MAP value and MAP settings:
MAP sensor
is very easy to diagnose, even without disassembling, just remove endplate.
- Measure MAP sensor supply (between pin3=+5V and pin2=GND )
- Reply: Voltage measured: pin3+pin2 voltage = 4,93V
- MAP sensor output (pin1)
- Reply: Pin1+Pin2 voltage = 0,08-0,4V
- Check the 1k protection resistor on the MAP sensor small PCB. Measure voltage on both sides. Is the voltage same ?
- Reply: Voltage is same from sensor to pin1 (it means in front of and behind the resistor the voltage is same). It is just faulty MAP sensor? If yes, could you send me spare part or can i send you ECU?
- maybe some trace or soldering ?
- the signal can be traced to the BAV99 protection and the AVR pin, see GenBoard/VerThree/Schematic
- this happens extremely rarely, sorry about the inconvenience. If you can fix it (yes, you can), please use order comment in next order: "please subtract 150 EUR from list price, self-repair 400kPa MAP signal oid..."
- ECU is fixed now! I replace the faulty internal MAP sensor and the MAP reading is now right (101kPa when atmosphere and changed when i make a vacuum or pressure with mouth). Thank you very much for help and your offer. Today i will order another ECU for another customer. Please apply this discount on this order. Thanks and best regards guys! Tomas
- thanks, good job. Just for statistics: by chance, do you happen to know if it was really the freescale sensor at fault or supply or output (soldering) ? (both are extremely rare). Thanks.
- It was just faulty sensor. Soldering and supply was OK
- thanks, good job. Just for statistics: by chance, do you happen to know if it was really the freescale sensor at fault or supply or output (soldering) ? (both are extremely rare). Thanks.