I have a '98 Punto 75 (1.2 8v 180k km) and it seems to have developed an annoying jerking when driving. No injector light on dash. May still have error code in memory?
Happens usually when accelerating but also at steady speed (60km/h+). Position of throttle doesn't matter when this "Intermittent Power Reduction™" happens. Feels like flatspot when pressing gas during. Stops or can't feel it after 4500 rpm. Usually goes on for entire acceleration, but stops after a while at steady speed. Not all power is lost, just reduced noticeably.
Does this when hot or cold, but usually works for first few kilometers; works well for longer when ambient is very cold (-15C). Maybe related to air temp in engine bay? Lambda working nicely, idle and when driving. Idles ok. Headgasket changed 20k ago. No other HG symptoms.
This weirdness is also quite precisely timed at about 2 second intervals when it happens. Interval becomes longer when accelerating, but still consistent time between.
I have one spare coil pack I have switched around without help. Tried different leads too. Plugs normal. Seems to have a too consistent an interval to be a mechanical problem. Feels softer than loss of spark.
Map sensor hose intact, disconnecting causes stalling.
Any help?
Also is it normal for spark and injection to shutdown for 1-2 seconds when revs go to about 6000? Limiter? Rev gauge jumps to 0 and then back. It's very aggressive and I thought the engine seized up when it happened the first time.
Happens usually when accelerating but also at steady speed (60km/h+). Position of throttle doesn't matter when this "Intermittent Power Reduction™" happens. Feels like flatspot when pressing gas during. Stops or can't feel it after 4500 rpm. Usually goes on for entire acceleration, but stops after a while at steady speed. Not all power is lost, just reduced noticeably.
Does this when hot or cold, but usually works for first few kilometers; works well for longer when ambient is very cold (-15C). Maybe related to air temp in engine bay? Lambda working nicely, idle and when driving. Idles ok. Headgasket changed 20k ago. No other HG symptoms.
This weirdness is also quite precisely timed at about 2 second intervals when it happens. Interval becomes longer when accelerating, but still consistent time between.
I have one spare coil pack I have switched around without help. Tried different leads too. Plugs normal. Seems to have a too consistent an interval to be a mechanical problem. Feels softer than loss of spark.
Map sensor hose intact, disconnecting causes stalling.
Any help?
Also is it normal for spark and injection to shutdown for 1-2 seconds when revs go to about 6000? Limiter? Rev gauge jumps to 0 and then back. It's very aggressive and I thought the engine seized up when it happened the first time.