Wont rev past 3000 revs

Hi

I've just purchased a 2004 Micra 1.2 SE with 68k miles. I bought it with the engine management light on, so I knew that it had some faults.

My friend owns a garage so he has access to all the diagnosis equipment etc.

The car started and ran, albeit it sometimes took 10 turns of the ignition for it to start. It had a misfire and wouldnt rev freely when driven. It would rev all the way when in neutral. It intermittently cut out.


I replaced the battery. Gave it a full service, including new plugs. Oil was black. According to MOT certs only done 1000 miles per year for the last 4 years.Passed last MOT with no advisories.

The initial fault was Cam Shaft Sensor. This was replaced and the light went out. This cured the starting problem as well, and now fires first time. Still a misfire.

The Engine Management light came back on. Fault was coil on number 4 cylinder. This was replaced and again ran for a day (still with revving issues) and then light came on. Still a misfire. Still loses power.

Timing chain was changed and this was part of the full kit which contain replacement cogs etc. Engine Management light is out, doesn't have a misfire, starts first time, has no fault codes and runs like a dream. Chain definately needed changing, as it had stretched.

However, when driving the car, it doesnt accelerate correctly. Its as if someithing is holding it back. First gear is ok, then from second gear it wont, or is reluctant to go past 3ooo rpm. This is the same for 3, 4 and 5. However when it gets to 70 it runs fine. It has lost power on occasions and cut out. But as soon as the the ignition is turned, starts and drives. When its struggling to deliver power, if I dip the clutch, it will allow the car to rev all the way as it should. But when clutch is released, it struggles again.


When I got the car, the fuel filler neck was absolutely rotten, so this was replaced. My friend thought that rust or debris may be clogging the filter.There was loads of flaking rust around the neck so my friend removed the fuel tank, drained the petrol and cleaned the filter. Still no change.

Were both stumped! Any ideas??

 
OP
OP
S
Hi

I've just purchased a 2004 Micra 1.2 SE with 68k miles. I bought it with the engine management light on, so I knew that it had some faults.

My friend owns a garage so he has access to all the diagnosis equipment etc.

The car started and ran, albeit it sometimes took 10 turns of the ignition for it to start. It had a misfire and wouldnt rev freely when driven. It would rev all the way when in neutral. It intermittently cut out.


I replaced the battery. Gave it a full service, including new plugs. Oil was black. According to MOT certs only done 1000 miles per year for the last 4 years.Passed last MOT with no advisories.

The initial fault was Cam Shaft Sensor. This was replaced and the light went out. This cured the starting problem as well, and now fires first time. Still a misfire.

The Engine Management light came back on. Fault was coil on number 4 cylinder. This was replaced and again ran for a day (still with revving issues) and then light came on. Still a misfire. Still loses power.

Timing chain was changed and this was part of the full kit which contain replacement cogs etc. Engine Management light is out, doesn't have a misfire, starts first time, has no fault codes and runs like a dream. Chain definately needed changing, as it had stretched.

However, when driving the car, it doesnt accelerate correctly. Its as if someithing is holding it back. First gear is ok, then from second gear it wont, or is reluctant to go past 3ooo rpm. This is the same for 3, 4 and 5. However when it gets to 70 it runs fine. It has lost power on occasions and cut out. But as soon as the the ignition is turned, starts and drives. When its struggling to deliver power, if I dip the clutch, it will allow the car to rev all the way as it should. But when clutch is released, it struggles again.


When I got the car, the fuel filler neck was absolutely rotten, so this was replaced. My friend thought that rust or debris may be clogging the filter.There was loads of flaking rust around the neck so my friend removed the fuel tank, drained the petrol and cleaned the filter. Still no change.

Were both stumped! Any ideas??
My firend has just called to say the fuel pressure id flutuating!
 
Did the sensors go to 0v after it cut out? Have you checked all the basics like plug gap etc. I know it sounds common sense but seems like there is quite a bit of guess work going on and no figures or readings to be used for diagnosis.
 
OP
OP
S
A quick update regarding this issue. Basically I filled the tank with Unleaded Plus (Momentum) and then drop it about 40 miles. Since then its been spot on!
 
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