Thread: Running rough and lacking power

I've just changed the fuel pressure regulator and unfortunately no change whatsoever. Simon I might take you up on the offer and call past during next week and see if your Nanocom can isolate the problem. My Nanocom FCR Does not recognize any faults in the car. Is your Nanocom licensed for more than 1 vehicle? Hopefully it will be a relatively cheap and easy fix.
Just as a side comment. Replacing the fuel pressure regulator is like many other RR items fairly simple once everything around it is removed or moved out of the way. Accessing one of the retaining bolts is a PITA. The top one is straightforward, but don't get lulled into a false sense of security, the bottom one is hidden in front of the coil pack providing access only for very small hands! Unfortunately I have relatively large hands

Gary

Originally Posted by PhilipA

To me the most likely cause is simply that the water temperature sensor has gone high resistance either because of a dirty contact or stuffed sensor. This confirmed by the error message. The only way the ECU knows the temperature is from the sensor. It doesn't matter if its 50C outside!LOL

Try a new sensor first. Just to confirm AFAIR there should be 300 Ohms resistance at 82C plus so if it is 1000 Ohms or whatever, the choke is still on.

Regards Philip A

Edit: there's no open/closed loop because it has no Oxygen sensors to provide feedback
There are three temperature sensors: air intake temp sensor, coolant temp sensor and fuel temp sensor (into the rail)... The fuel temp sensor is especially sensitive..
which one did you check?

U/S sensors would normally throw a code (as listed in RAVE)

,,,not sure if this is relevant...Have you checked the Positive crankcase ventilation hoses from the rocker covers for blockages?

Crankcase hoses all appear clear and unblocked, and crack free.
Looking at Torque app I can see:
air intake temp around 38
Coolant temp 86
No readout that I can find for fuel temp

Not sure if it's relevant but ambient temperature is showing as -(minus)40 in the Torque app but correct on the dashboard HEVAC panel at 32

Gary

I have it unlocked for the p38, but not engine management side of things. I can pick up basic stuff, but not really looked into it any deeper.
Your welcome to come and try.

Hi

Just a basic suggestion here, have you removed one or two of the plugs from each bank and examined them?

That may at least tell you if both banks are rich or only one and may help you narrow things down.

It could also be a failing ECU if all the sensors check out OK

Steve

Steve

One of my first tests when it started running rough was to remove all plugs. Good news there was that they all looked a very similar dark sooty colour. is the Colour you expect when running too rich. Which is also backed up by fuel consumption of around 20 l/100k. Just as well fuel is relatively cheap ATM

Simon

I don't think your Nanocom is going to find anything without the engine management unlocked. As I mentioned earlier I have the Nanocom FCR and no error codes are being produced.

Gary

Originally Posted by mtb_gary

Steve

One of my first tests when it started running rough was to remove all plugs. Good news there was that they all looked a very similar dark sooty colour. is the Colour you expect when running too rich. Which is also backed up by fuel consumption of around 20 l/100k. Just as well fuel is relatively cheap ATM
Gary

I thought you would have done that, but it was worth asking!

Do you have a fuel pressure tester? It may be that the fuel pressure regulator is failing and over fueling

BTW I am getting 17l/100K with a good engine etc !

Steve

Steve

I just replaced the fuel pressure regulator yesterday, I too was hoping that was the fix. As for fuel, yes I would normally see figures around 16-18 l/100k around town. At present I am doing non peak hour and mainly freeway travel where I would previously been getting 13-15 l/100k. Also replaced yesterday in its routine service was the fuel filter, pollen filters, the air filter is also about to be changed as part of the service but unfortunately the filter was damaged in transit when it arrived. One phone call to TRspares and a new one is being sent as a replacement.

Gary