Civic 2000 Automatic jerking when put into D/R

[samson.naz]

I own a 2000 Honda Civic (Automatic Transmission) with DB15 engine. I purchased this car back in 2016 without the problem that I am about to mention.
The problem that I have with my car is that when it is put into D or R, it starts jerking and the RPM does not get stabilized, reaching to 500 or so and upon that when the AC is turned on, its worse and reaches around 300/400. While the car is moving, it does not do this since acceleration is there but when stopped at a signal it starts jerking while in the gear.
After last rain in Karachi, my car also got water inside. Since then the problem has become more as it is jerking a lot and when brakes are applied the engine goes off.
My mechanic said it is the gear which is problematic, he also consulted to a few more mechanics and they have the same diagnosis. Yesterday, we replaced the gear bought from Shershah but even with that there is same problem. Now the mechanic says that he will replace the ecu and check if the problem resolves or not.
upon scanning there is only secondary O2 sensor code coming and nothing of AT transmission.
Can anyone please help me out in figuring out the exact issue. If anyone had the same issue.

[Massive_One]

wow, so mechanic replaced gear without even doing diagnostics first ?
i think you should change the mechanic in stead of gear : (

it could be the throttle positioning sensor or idle air control valve which are causing the RPM to drop like that. did the mechanic check these little things first before going to the major gear job ?

[hasankhurshid29]

@shabbir.1
@rajaahmed96
@nfssaad
@hassan1991

[hasankhurshid29]

My mechanic said it is the gear which is problematic

How could he conclude that so quickly? How much you paid him?

[hasankhurshid29]

The problem that I have with my car is that when it is put into D or R, it starts jerking and the RPM does not get stabilized, reaching to 500 or so and upon that when the AC is turned on, its worse and reaches around 300/400.

Problem seems pretty simple. Get your throttle body serviced and idle air control valve (iacv) cleaned and you are good to go.

[hasankhurshid29]

After last rain in Karachi, my car also got water inside. Since then the problem has become more as it is jerking a lot and when brakes are applied the engine goes off.

Some wiring maybe loose and water get inside the connectors of some sensors

[dani_kk]

Civic 2000 sometimes also jerks because of worn out axle inner. Had one car, there were no codes. Found out worn out axle inner causing the jerk.

[nfssaad]

first tell us if the engine is original or changed? pkdm or jdm?

this appears to be a case of loose/bad contact wiring.

the ecu is not giving signal to the engine to increase throttle, when car is in gear or AC is turned on.

[hasankhurshid29]

He said that the problem was not there when he bought. Maybe only iacv and throttle body cleaning needed

[nfssaad]

probably moisture. contacts can become dirty/loose later on.

this is not at all a gearbox fault

[shabbir.1]

If the ecu is hunting for an O2 sensor reading this indicates that the engine or ecu has been changed, as O2 sensor is not available in PKDM civic. Anyhow this problem is not directly linked with the rpm fluctuations especially in post rains scenario.

For RPM problem you need to check these two things:
1. Shift position signal(s) to the ecu
2. Idle air control valve (IACV/ EACV)

For shift position signal troubleshooting you have to access the ecu to check issues with the wiring.

Testing IACV is rather easy, while the engine is started remove conenctor from IACV and see if the RPM drops. If it does, the IACV is not dead, though it may need cleaning from inside. Switch off the engine and reconnect the conenctor, also remove the battery negative terminal for 10 sec to clear the IACV code.

[nfssaad]

my car has no check engine light. would it still have codes stored?

did a full throttle body service this weekend, due to unstable idle.

so much black gunk in the iacv, emptied a whole bottle of brake cleaner.

issue is fixed now. probably the iacv was sticking

[shabbir.1]

ECUs offered in 90's era Civics were pretty dumb. CEL, mostly, keeps showing until the problem persists and key is in ON position. In few cases ECU's backup fuse or the battery terminals has to be removed to clear the CEL.

On the contrary ABS control unit offered in same era Civics would keep all codes stored in its memory no matter the ABS check light stays ON or not and won't clear even with removing the battery terminal.

[hasankhurshid29]

my car has no check engine light. would it still have codes stored?

No. It doesn't store codes.

[samson.naz]

Sorry being away for a long time. I have changed the mechanic and shown to another person (reference of one friend). As per him the car is giving codes of ELD (Electric Load Detector) and Secondary O2 sensor. The secondary O2 sensor was never installed in it as there is no space to be seen beneath the exhaust manifold. Primary O2 is attached. As for the ELD, we are unable to find a fuse box with a properly working ELD unit. Now the mechanic says that either I find a fuse box or change the gear to ATF (currently CVT installed). He says ATF gear does not connect to the ECU and will not be having this issue. I am not convinced with his response. Please suggest where to find a proper fuse box for my car or what should be the next steps. I am from karachi and the mechanic has searched Sher Shah, Plaza for the fuse box. Any help/suggestion would be appreciated. I love my car and want to keep it but with this issue unresolved, it is a headache to drive.

[shabbir.1]

Please confirm engine, transmission and ecu codes.
You can easliy get a used fuse box for this car with ELD from your local junk dealers, don't know why your mechanic failed to find one.
Linking an ELD with gear box ia totally absurd.

[samson.naz]

He did not send me the pictures of the codes however, he states that he codes were for ELD (P 1298) voltage high I think and O2 sensor (both Primary & Secondary). I am also not satisfied with the diagnosis since ELD is related to electrical load and the gear box is not related to it (I do not have much knowledge).

[shabbir.1]

No, I didn't ask about the diagnostic codes. I inquired about the codes/numbers engraved/written on the engine, transmission and ecu to identify what setup have you got in your car, so as to apprehend the problem correctly and suggest a solution accordingly.

[syedfaizan1]

i had same Engine in my City 2000, its due to IACV valve in thortael Body. just open it Clean it its Jammed due to which your RPM Flutuate and when you put in D it JERK hard, so its due to Thoratel Body. Your mEchanic is not experience, change your mEchanic and re

[syedfaizan1]

D15b dont have any o2 Sensor.