davidgpsport
New member
- Joined
- Jun 20, 2020
- Messages
- 5
- Points
- 3
Hello, I’m writing to ask for a bit of help with my poor Grande Punto 1.9 JTDm.
About half a year ago, it started losing power. The symptom felt like the engine was being choked of fuel: jerking when cold, very sluggish when cold, barely accelerating, and until the engine warmed up a little, it wouldn’t rev properly.
I should mention the car has been REMAPPED since 200,000 km and now has 360,000 km. About 15,000 km ago, one piston broke (it cracked on the side). I bought a piston with a connecting rod from eBay UK, replaced it, did the timing belt, water pump, etc. It was my first engine teardown, but it turned out great. It doesn’t burn oil, doesn’t consume coolant, and it used to run really well (around 160 hp with the stage).
The EGR has been deleted for 10 years, and the throttle body is disconnected and electronically disabled (the throttle plate has an electrical issue).
But now, it feels like a Renault 5 with the carburetor choking the engine.
Symptoms:
What have I checked so far?
I checked that the throttle body is open so it doesn’t choke the engine. Everything is OK.
But I’ve run out of ideas.
If I disconnect the MAP sensor, the engine goes into limp mode and it no longer chokes, but there’s no turbo. It uses a safe map with little fuel, so it doesn’t choke.
It basically turns into a naturally aspirated car, actually a bit worse.
So, what other sensor could regulate the mixture and cause the engine to choke?
If it were a faulty injector, then even with the MAP disconnected, the engine would still be choking, but that’s not the case.
Thanks! No error codes are being generated. I also tried disconnecting the pre-cat lambda sensor, but I didn’t notice any improvement either.
About half a year ago, it started losing power. The symptom felt like the engine was being choked of fuel: jerking when cold, very sluggish when cold, barely accelerating, and until the engine warmed up a little, it wouldn’t rev properly.
I should mention the car has been REMAPPED since 200,000 km and now has 360,000 km. About 15,000 km ago, one piston broke (it cracked on the side). I bought a piston with a connecting rod from eBay UK, replaced it, did the timing belt, water pump, etc. It was my first engine teardown, but it turned out great. It doesn’t burn oil, doesn’t consume coolant, and it used to run really well (around 160 hp with the stage).
The EGR has been deleted for 10 years, and the throttle body is disconnected and electronically disabled (the throttle plate has an electrical issue).
But now, it feels like a Renault 5 with the carburetor choking the engine.
Symptoms:
- Total lack of power
- Engine choked
- Struggles to rev up (hard to reach even 1,500 rpm)
- Lots of dark (dark gray) smoke
- Strong smell of badly burned fuel, horrible
What have I checked so far?
- New vacuum hoses
- New N75 valve that controls the turbo
- New MAP sensor
- New MAF sensor
- New coolant temperature sensor (located on the thermostat)
- New battery
- Disassembled the turbo, removed the carbon buildup (fully opened the turbo, checked the variable geometry, cleaned it, and it works perfectly)
- By applying vacuum with a big syringe, the turbo actuator rod moves normally
I checked that the throttle body is open so it doesn’t choke the engine. Everything is OK.
But I’ve run out of ideas.
If I disconnect the MAP sensor, the engine goes into limp mode and it no longer chokes, but there’s no turbo. It uses a safe map with little fuel, so it doesn’t choke.
It basically turns into a naturally aspirated car, actually a bit worse.
So, what other sensor could regulate the mixture and cause the engine to choke?
If it were a faulty injector, then even with the MAP disconnected, the engine would still be choking, but that’s not the case.
Thanks! No error codes are being generated. I also tried disconnecting the pre-cat lambda sensor, but I didn’t notice any improvement either.
- Model
- Grande Punto 1.9 JTDm 130
- Year
- 2006
