XU10J4R Idle problem after swapping engine.

[FrancoSss 0]

Hi everyone.

I'm having a problem with my RPM.

Everything is OK while driving, acceleration is good and no problems. except when I want to stop and when parking, the RPM goes down quickly to 500-450 and then goes up to 900 then back to good 800-850. some times it goes off especially when the air conditioner is working!

 

In general the RPM goes down to 500 and fluctuates back and forth to become stable after seconds. ( it tries to resettle after this drop ).

1- I changed the stepper 3 times!, nothing happened.
2- checked the ECU and no faults detected, numbers were OK. I even changed the ecu several times with no changes!
3- Throttle intake is clean.
4- after warming up the engine, if I disconnect stepper cable the engine becomes stable and fine.
5- after disconnecting stepper the ecu reads no faults on (PP2000) and this was tested on three different ecu's.

Technician claimed that sensors are good.

In general RPM does not go up high numbers, it only goes down 500 and back to 1100 max then it starts to stabilize at 800.

NOTE: car was 405 1.6L engine, I swapped engine with Citroen Xantia 2.0L XU10J4R one, I faced this problem after swapping. After discussing this matter with others, it seemed a common problem after upgrading!. Same problem keeps happening to others not only me! it seems like a general issue with different technicians and mechanics after upgrading to XU10J4R engines (Peugeot + Citroen)!

 

Is there something missing after upgrading?

Is it an ECU common issue?

are there any additional (electrical or mechanical) parts that must be installed after upgrading to avoid this matter?

 

Is it a known common problem?

 

Did anybody do the same swap and everything is OK?

 

Thanks.

 

Edited December 6, 2021 by FrancoSss

[welshpug 1,657]

are you using the xu10 ecu and loom?

[FrancoSss 0]

3 hours ago, welshpug said:

are you using the xu10 ecu and loom?

Yes, both came with engine, ecu is Bosch MP5.2   63

[Edx1020 0]

On 12/6/2021 at 10:54 AM, FrancoSss said:

Hi everyone.

I'm having a problem with my RPM.

Everything is OK while driving, acceleration is good and no problems. except when I want to stop and when parking, the RPM goes down quickly to 500-450 and then goes up to 900 then back to good 800-850. some times it goes off especially when the air conditioner is working!

 

In general the RPM goes down to 500 and fluctuates back and forth to become stable after seconds. ( it tries to resettle after this drop ).

1- I changed the stepper 3 times!, nothing happened.
2- checked the ECU and no faults detected, numbers were OK. I even changed the ecu several times with no changes!
3- Throttle intake is clean.
4- after warming up the engine, if I disconnect stepper cable the engine becomes stable and fine.
5- after disconnecting stepper the ecu reads no faults on (PP2000) and this was tested on three different ecu's.

Technician claimed that sensors are good.

In general RPM does not go up high numbers, it only goes down 500 and back to 1100 max then it starts to stabilize at 800.

NOTE: car was 405 1.6L engine, I swapped engine with Citroen Xantia 2.0L XU10J4R one, I faced this problem after swapping. After discussing this matter with others, it seemed a common problem after upgrading!. Same problem keeps happening to others not only me! it seems like a general issue with different technicians and mechanics after upgrading to XU10J4R engines (Peugeot + Citroen)!

 

Is there something missing after upgrading?

Is it an ECU common issue?

are there any additional (electrical or mechanical) parts that must be installed after upgrading to avoid this matter?

 

Is it a known common problem?

 

Did anybody do the same swap and everything is OK?

 

Thanks.

 

I did the exact same swap, and guess what.?! Samee probleeeeem. Its my daily car so I just got "used" to it..? I dont get with that happends

[DamirGTI 342]

From memory , on early 2.0l Xu10j4r's there used to be fault but can't remember precisely it's either with the idle stepper motor wiring harness and/or idle stepper motor circuit/driver inside the ECU going bad thus shifting idle speed all over the place .. one or the other or even both , google a bit about that should be able to find some info still on some of the old Peugeot/Citroen forums .

 

Somewhat similarly as with the Xu7jp4's with the Sagem ECU's on which the ignition coil driver inside the ECU used to burn out when the coil-pack was near the end of it's life , by sending voltage spike back to the ECU and thus fried the coil driver .. firstly manifested very intermittent every now and then by some second or two jerking/missing sensations , and then after time getting progressively worse up to a point where engine starts cutting out more frequently , and eventually completely creating no start from there on .. needing the ECU repair or replacement in order to fix it .

 

D

Edited January 11, 2023 by DamirGTI