Ste.Sales
15th January 2015, 21:36
Hi, im new to forum and would like some help with diagnosing the problem.
I have a 2004 rover 75 1.8 turbo and have a very annoying issue when the engine is cold. The engine fires up first turn of the key and idles at ~1000rpm for approximatley 30 secs, then the idle drops to 750rpm ish and fluctuates up and down with vibrations felt through the car. The car drives fine in first and second gear, but when changing to 3rd or higher at low speed (revs under 2000rpm) the engine generates a light pulse. If I try to accelerate, i get a very unnerving rapid vibration/juddering from the engine, almost like its misfiring, and it will not pick up speed. The higher the gear, the worse it is...higher engine load I suppose. As soon as the engine passes ~2000 rpm the juddering disappears and it picks up well. As I said before this only happens when the engine is cold, as soon as the temp guage starts to move, everything starts to smooth out again. When fully warm, no problem whatsoever, no loss of power (pulls like a train) no juddering and a rock steady idle at 750rpm.I have already tried diagnosing the problem and here is what i have done:
Both ignition coils replaced
both ht leads replaced
spark plugs replaced ( gapped at .7mm first, now back to 1mm- no difference)
Full oil change and filter change
Air filter changed
Inlet manifold gasket replaced
Exhaust manifold to turbo gasket replaced
Coolant temperature sensor replaced
Changed turbo boost controller vacuum hoses
Checked for vacuum/boost leaks
Checked both oil and coolant, nothing mixing, no overheating or headgasket issues
No smoke from the exhaust
Checked plenum - bone dry
Compression tested engine cold, got 165,170,170,170 (cylinder1,2,3,4)
Compression tested engine warm, got 180,184,180,180
No check engine light
No fault codes recorded
I have had the car at a friend of a friends garage and they couldnt tell me what is wrong. Am I missing something? Fuel system maybe? Since it is temperature related, i was sure the cts was shot - seems not. Any help or suggestions will be greatley appreciated. Thanks
I have a 2004 rover 75 1.8 turbo and have a very annoying issue when the engine is cold. The engine fires up first turn of the key and idles at ~1000rpm for approximatley 30 secs, then the idle drops to 750rpm ish and fluctuates up and down with vibrations felt through the car. The car drives fine in first and second gear, but when changing to 3rd or higher at low speed (revs under 2000rpm) the engine generates a light pulse. If I try to accelerate, i get a very unnerving rapid vibration/juddering from the engine, almost like its misfiring, and it will not pick up speed. The higher the gear, the worse it is...higher engine load I suppose. As soon as the engine passes ~2000 rpm the juddering disappears and it picks up well. As I said before this only happens when the engine is cold, as soon as the temp guage starts to move, everything starts to smooth out again. When fully warm, no problem whatsoever, no loss of power (pulls like a train) no juddering and a rock steady idle at 750rpm.I have already tried diagnosing the problem and here is what i have done:
Both ignition coils replaced
both ht leads replaced
spark plugs replaced ( gapped at .7mm first, now back to 1mm- no difference)
Full oil change and filter change
Air filter changed
Inlet manifold gasket replaced
Exhaust manifold to turbo gasket replaced
Coolant temperature sensor replaced
Changed turbo boost controller vacuum hoses
Checked for vacuum/boost leaks
Checked both oil and coolant, nothing mixing, no overheating or headgasket issues
No smoke from the exhaust
Checked plenum - bone dry
Compression tested engine cold, got 165,170,170,170 (cylinder1,2,3,4)
Compression tested engine warm, got 180,184,180,180
No check engine light
No fault codes recorded
I have had the car at a friend of a friends garage and they couldnt tell me what is wrong. Am I missing something? Fuel system maybe? Since it is temperature related, i was sure the cts was shot - seems not. Any help or suggestions will be greatley appreciated. Thanks