astra lacking power

Hopefully someone will identify with this problem.

last week totally out of the blue my P reg Astra 1.6 16V sport wouldn't accelerate out of a corner, even with the throttle fully depressed the engine just struggled and eventually coming to a stop. I restarted after a minute or so and drove another few yards off the road, all the time it was struggling to accelerate.

My first thoughts were fuel problems, so I changed the petrol filter (I have had the car less than 6 months so wasn't sure when it was last changed). This didn't help the problem at all. The car has the Multic S (multipoint injection) fuel injection system, so there is not a lot you can check with it, but there is no light on the dash coming on to say there is an ECU problem.

I have tried various things like unplugging the Lambda sensor in case that was cutting the fuel back, no change. I have lifted the rear seats, and you can hear the fuel pump so I assume it is working ok! I have also checked the air filter and spark plugs, both seem ok (spark plug problems would shop up at tickover anyway wouldn't they?).

I have noticed there is what appears to be a fuel pressure regulator on (I think) the return fuel line, which I assume works on the vacuum created when the throttle is opened to build up fuel pressure? perhaps this is the problem?

I was hoping for any ideas about what this could be (or if anyone has suffered similar). To recap, it runs fine at tickover, and if you press the throttle, but as soon as you attempt to drive the car it started this problem

probably the mass air flow sensor.

some one help me. please!!!!
the car just doesnt rev up beyond 2500 rpm. have checked fuel pump,injector and plugs all ok. maybe i need to take it to a workshop

take it to a garage and have it scanned for codes,will save you money in the long run,
still think it,s the m.a.f. though!

http://www.forumsireland.com/printthread.php?t=1442

i have exactly the same problem.Astra 2000 engine type X12XE.At 50000km,the
acceleration of the car in the first 3gears started to
be very poor with heavy shaking.I have sent a letter to GM US and from your forum i learn that this problem is a universal one.i live in Egypt and virtually all my models have the same problem.it should be replaced for free (mass air flow sensor). or complete refund..

hey by what you have all said have you checked the throttle i had the same problem and found it to be that there is a small porrt on the throttle that block and causes a lack in power or try the throttle position sensor good luck

carroll: The throttle body has an idle air bypass which is what your describing.

Most common problem listed for these cars is also the crank angle sensor or the camshaft sensor. If these are faulty, the ECU limits engine revs to prevent any damage and enable you to drive it for servicing.

take it to a garage and have it scanned for codes,will save you money in the long run,
still think it,s the m.a.f. though!

correction: these engines use a map sensor

could this be heat soak/ could the map sensor feed be blocked on the inlet manifold

Hi all in response to the original post it sounds a lot like an EGR problem, these cars are prone to it once they have a few miles on and start to use a little oil, basically the EGR (exhaust gas recirculation) valve jams in the open position and causes a sudden loss of power often without fault codes as it happens so quickly the ECM cant compensate in time before the car stops, mass air flow sensor problems usually result in a loss of power and erratic running as the ECM does not know the actual air flow rate in order to calculate fuel load, it also sounds like some of the other posters particularly the person with the Z12XE may have coil pack troubles, Hopefully this helps.

Regards

John

I had the same problem with my Astra,
What about the catalytic convertor, that had to be done on mine. To be honest I left it so long to replace the catalytic convertor that it damaged the car in other ways, and it never went back to performing the way it had been before.