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Can someone please have a look at this datalog and let me know the problem, could it be the TPS that is cause my rough running?

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You got one for when its up to temperature?

you need to get your car up to operating temp and take it for a drive and then take a log do a couple of high rpm runs and a hard acceleration run and a low rpm high load run in 5th gear then post it up, from what you have put there your left o2 sensor seems a bit lazy but that could be just the car not at operating temp

from the look of that your o2 sensors are not going through the full operating range should be hitting varying high to low but yours arnt hitting the .9 high reading, plus for me thats running a bit hot , whens the last time you serviced your cooling system, tps is slightly low and is it idleing at 900rpm?

  • Author
from the look of that your o2 sensors are not going through the full operating range should be hitting varying high to low but yours arnt hitting the .9 high reading, plus for me thats running a bit hot , whens the last time you serviced your cooling system, tps is slightly low and is it idleing at 900rpm?

 

When the revs reach about 1850 the timing gauge seems to go crazy, I was holding the revs where the missfire apears to be happening. I was hoping someone could shed some light on what would cause this. As for the cooling system I have flushed the radiator today and will be adding new coolant tomorrow, I will do a run tomorrow as you suggest above and will post the results.

Despite the TPS setting been incorrect this in itself is unlikely to cause rough running, however there are some conflicting figures with the first screen shot, were you holding the throttle down or not? the idle switch is showing OFF so unless you had the throttles open then you need to resolve that, also the timing figure is very high, normall 35deg is the normal at that temperature, the injector figure also seem in conflict with the revs and timing.

 

It would look like you may well have more than one issue and you need to work through them one by one and then do more tests, more screen shots once the tps issues have been adressed would be good and don`t be fooled by clear fault codes in ecu as an example often air flow meters drift off their correct operating range and DO NOT show a fault but cause incorrect fueling, could be why you have an odd injector reading too.

 

 

Daveman

 

 

 

looks like a potential afm problem, given the engine temperature shown, the injector and

  • Author
Despite the TPS setting been incorrect this in itself is unlikely to cause rough running, however there are some conflicting figures with the first screen shot, were you holding the throttle down or not? the idle switch is showing OFF so unless you had the throttles open then you need to resolve that, also the timing figure is very high, normall 35deg is the normal at that temperature, the injector figure also seem in conflict with the revs and timing.

 

It would look like you may well have more than one issue and you need to work through them one by one and then do more tests, more screen shots once the tps issues have been adressed would be good and don`t be fooled by clear fault codes in ecu as an example often air flow meters drift off their correct operating range and DO NOT show a fault but cause incorrect fueling, could be why you have an odd injector reading too.

 

 

Daveman

 

 

 

looks like a potential afm problem, given the engine temperature shown, the injector and

 

Yes I was holding revs to show missfire.

  • Author
you need to get your car up to operating temp and take it for a drive and then take a log do a couple of high rpm runs and a hard acceleration run and a low rpm high load run in 5th gear then post it up, from what you have put there your left o2 sensor seems a bit lazy but that could be just the car not at operating temp

 

I have had the car out tonight and followed your instruction, I would be greatfull for any suggestion you could make!

 

Cheers,

Andy B

looking at those the vct isnt engaging and the egr valve is on and off all the time its even opening up on heavy throttle when it should stay closed.

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