power zapped? different to missfire!

[jackoni]

Morning folks

Past few weeks when giving it the beans the car seems like it is zapping the power from me under load! I have changed the coils to 2.0 versions when i had a missfire before but this feels like the power is being zapped away for 1 second or 2, where as the coil missifre was an instant bang and away you go again!
No codes showing on he handheld reader.

Thank you

 

[Muttley]

Traction control, ESP or EDL? Or the map cutting the power due to misfire, if you are not using 98 RON fuel or an octane booster?

Just guessing, I have a diesel which manifests different problems

 

[jackoni]

Traction control, ESP or EDL? Or the map cutting the power due to misfire, if you are not using 98 RON fuel or an octane booster?

Just guessing, I have a diesel which manifests different problems

Hi Muttley

Definitly not traction control, always reach down and turn it off before a boost....to save hitting the brick wall!! lol

Highest RON fuel we can get in NI is 97 BP Ultimate

What kind of components are liable to cause miss fires/instant power theft?

 

[Muttley]

I have to assume that your map was done when running with 97 RON fuel then, or that it is already made for such fuel if it is a generic map.

The engine management system will retard the ignition if it thinks there is a misfire, which is detected by the knock sensors, so a failure of one of the knock sensors may cause this sort of problem. A scan for logged problems using VCDS or a code reader would be a good start to see if any faults are logged and what they are.

Otherwise, plugs would be the next thing to check, for any wear or damage. How old are the plugs? Replacement interval is 40K miles.

 

[jackoni]

I have to assume that your map was done when running with 97 RON fuel then, or that it is already made for such fuel if it is a generic map.

The engine management system will retard the ignition if it thinks there is a misfire, which is detected by the knock sensors, so a failure of one of the knock sensors may cause this sort of problem. A scan for logged problems using VCDS or a code reader would be a good start to see if any faults are logged and what they are.

Otherwise, plugs would be the next thing to check, for any wear or damage. How old are the plugs? Replacement interval is 40K miles.

Only have a handheld reader with no codes showing...wish there was sometimes so i knew!

Plugs have been changed to Iriidium heat rating 7 so 1 degree cooler....could the gaps possibly be out? Was told they were fine to fit as they were, no gap adjustment needed...could be wrong tho!Only fitted 6 months ago and new dealer bosch MAF last week.

 

[Muttley]

Plug gap is 0.8mm for the recommended NGK plug, which is heat range 6, one step hotter (not one degree, but I think you knew that). Worth checking that your plugs are not too far out from this measurement.

A colder plug will tend to run cool, and if you are generally running at street speeds with only the occasional fast burn then they may be fouling. When you check the gaps, have a look for fouling.

Some good pictures and explanation on these two pages.

 

[jackoni]

Yeah thats what i meant Muttley lol I also have 2.0 coils and for some reason think your meant to adjust the gap possibly when using the NGK BKR7EIX plugs! Trying to find out now to no avail!