Civic D15B(Exi) Idle issue

hammi (hammi) 2021-01-17 00:35:28 +0500 #21

Yes the car had no coolant in it.
I have done the following test.
1. Started engine and lets it reach normal opt temp
2. Disconnected the IACV grip no change in RPM noticed
3. Removed the magnetic IACV altogether no change in RPM noticed
4. Tried to close the magnetic valve with hands the RPM dropped.

Is that normal or the inner thermo valve is damaged/rusted?

hammi (hammi) 2021-01-17 00:39:26 +0500 #22

Yes the car does overheat sometimes specially in rushy traffic. Although temp these days is low. Im assuming thermo is partially stuck

hammi (hammi) 2021-01-17 00:43:26 +0500 #23

Is there a way to check if the magnetic IACV is working correctly?
I read you had written in a post to check the IACV of a lancer 2005 using voltmeter and measure its resistance a healthy IACV should have resistance > 30ohms.
Can the same test be applied on this IACV too?

Hassan1991 (Electrical Engineer ) 2021-01-17 00:49:01 +0500 #24

Yes check the thermostat and change if required. Also check the cooling system first. Tap water can cause pipes to corrode and block.
Yes you can check this iacv with same method. But search for its resistance.

hammi (hammi) 2021-01-17 00:55:27 +0500 #25

I got the radiator serviced and it had quite a a lot of rust in it im pretty sure the waterbody needs replacement too.
I want to fix the idle issue first its very annoying. The plugs were black car is running rich will a bad IACV make the car run rich?

Hassan1991 (Electrical Engineer ) 2021-01-17 01:16:28 +0500 #26

Yes. Engine is ment to operate in a certain temperature range. Before that range ecu riches the mixture assuming engine is cold.

hammi (hammi) 2021-01-17 02:03:10 +0500 #27

Got it. Also there is another question about the transmission of the car. It has a auto tranny from civic Exi 1997. The tranny is controlled by a wire which connects to the accelerator. The tranny has two solenoids on it too. Tranny jerks on a down shift I asked the mechanic if the valve body/solenoids are stuck or need replacement he said these solenoids are of no use even if you remove them altogether it wont affect anything.
Do these gears lock torque convertor on certain speed or rpm because i have never felt the gear locking the TC no matter what speed.

Hassan1991 (Electrical Engineer ) 2021-01-17 02:11:26 +0500 #28

i not sure about it. Not into auto at all.
@Xulfiqar sir can guide you.

Xulfiqar (Xulfiqar) 2021-01-17 02:39:08 +0500 #29

Those solenoids control the torque converter lockup? Its 2 stage lockup on Honda.

And having them disconnected will result in overheated gearbox at high speed and rpm and also really bad fuel mileage, they are ecu controlled and are commanded when engine is fully warmed up and running in od.

For the idle motor, it maybe that someone has either damaged the wiring. You should have a 3 wire iscv if I recall right.

Does your engine ecu have any error codes stored?

hammi (hammi) 2021-01-17 09:58:32 +0500 #30

Ahh so thats the problem! The solenoids aren’t getting any signal im sure because the ECU is from a Manual Honda Capa. First I need a automatic Tranny ECU and get the wiring redone for them to operate.
It has a 3 wire ISCV. I got the wiring checked the wiring had no issues. It had one DTC of a missing ELD sensor.

Xulfiqar (Xulfiqar) 2021-01-17 10:52:05 +0500 #31

If it is looking for eld, its not the original ecu that was installed in atlas cars

hammi (hammi) 2021-01-17 10:55:31 +0500 #32

Its a accord 1987 with a 1997 Exi engine in it. Its a Japanese spec ECU PEJ-J01. Sir can you please guide which ECU will be best for this engine. As far as I have searched this Engine comes with P2C or P2E Ecu.

hammi (hammi) 2021-01-17 10:56:19 +0500 #33

Its a 1.5 sohc non vtec D15B with P2A-5 head.

hammi (hammi) 2021-01-17 11:16:54 +0500 #34

Sir what do you conclude from the following test

Started engine and lets it reach normal opt temp
Disconnected the IACV grip no change in RPM noticed
Removed the magnetic IACV altogether no change in RPM noticed
Tried to close the magnetic valve with hands the RPM dropped.

I just cant figure out how does the IACV works. A mechanic told me if you remove the IACV motor altogether the rpm should raise as per him the motor closes the valve and brings the rpm down. What I think is its the opposite. The Rpm should drop once IACV is removed. I cant understand if the IACV works clockwise or anticlockwise.

hammi (hammi) 2021-01-18 02:20:32 +0500 #35

@Hassan1991 Got the timing done using a timing gun it was quite retired. He moved the distributor almost an inch to adjust. Pick has improved and throttle is more responsive. Mechanic has blocked the IAC Port will clear and see if RPM stabilises.

@Xulfiqar I got the P2C ECU for Auto transmission. I removed the solenoid grip and it gave a code of Solenoid B circuit break or something like that I reconnected and DTC was gone hence the wiring has been done properly.
It was giving a DTC of IMA(Idle mixture actuator). I also got the IMA fitted. Now whats the ideal voltage of IMA for best fuel consumption?

Hassan1991 (Electrical Engineer ) 2021-01-18 02:59:10 +0500 #36

you have to get it checked by installing an external sensor to measure lamda. between middle will be 2.5v.

hammi (hammi) 2021-01-18 12:32:04 +0500 #37

Cant it be checked on the scanner?

Hassan1991 (Electrical Engineer ) 2021-01-18 13:31:07 +0500 #38

Scanner will tell fuel trims. External sensor is needed for lambda.

hammi (hammi) 2021-01-18 13:59:20 +0500 #39

Scanners tells the value of the IMA if you rotate the screw on the IMA the value changes on the scanner

Hassan1991 (Electrical Engineer ) 2021-01-18 14:00:43 +0500 #40

You can even check it by multimeter. I'm talking about lambda air fuel ratio.