Astra Owners Network banner
1 - 7 of 7 Posts

·
Registered
Joined
·
22 Posts
Discussion Starter · #1 ·
Hi

I'm hoping someone will be able to give me some suggestions. My car developed a fault two nights ago when I was 5 mins from home, drove home and parked it up as was 10pm and cold. The next day I turned it on and the engine light was gone, drove 5 mins down the road and it was back. I have a wireless OBD2 so I pulled in and took a look. I was getting a P0105 code which had to do with the MAP sensor circuit, I cleared the fault hoping it would go away but no joy.

I mi went to turn the car back on but the OBD2 had completely drained the battery and it wouldn't turn over. My battery had been struggling the past week or so to start the car with the cold. I was on a hill liuckily so I was able to jump start and turn around for home.

But it the time I got home I had no power steering, no speedometer or Rev counter etc... Basically had no electricity at all from the battery. I attached the jump leads to my wife's car and left them on for about 10 mins to give my battery a bit of a charge and it started up, disconnected and left to run but the battery drained again within 10 mins. The alternator doesn't seem to be charging it but it its self was changed 30k miles ago.

I thought maybe the battery has had it so I swapped it with the battery in my wife's car and tried hers in mine. my battery charged up fine in her car and again her battery went flat in mine so the battery is fine, the alternator isn't charging it.

My next step is to test the alternator but I'm not entirely sure how to achieve this. But also, this all started with the MAP sensor fault so are the connected on the same circuit and could this be a wiring fault? The car is 2005 model and has 100k so I'm not going to sown a lot of money on it. The last time the alternator cost £350 to replace.

When I had my battery back in and charged from my wife's car I put the OBD2 back on and I was able to get a MAP read, it was sitting at about 130kpa at idle but no change when I put the accelerator down in neutral. I then took a read of the load and it was sitting around 15 at idle and jumped to around 85 when reving the engine in neutral. Does this again point to a wiring problem or do you think from those values the sensors needs replaced?

I did another read and I had three fault codes the second time, P0560 System voltage, P0234 Turbo/Supercharger "A" Overboost condition, P0105 Manifold Absolute Pressure/Barometric Pressure Circuit.

I fear this could be the end of the Astra ?!

Quite a long post but seems like it's going to be a tricky one to solve!

Thanks in advance guys!
 

·
Registered
Joined
·
6,242 Posts
Replace the battery and alternator, map sensor needs done as well and more than likely the boost control solinoid


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #4 ·
Thanks for the replies!

Is is there anyway I can test the alternator, Map sensor and boost control solenoid (can you tell me where this is on the engine) like with a multimeter??

Are all these parts on the one circuit? Just strange that I'd have separate problems all happening at exactly the same time.

Also are these jobs I can do myself? I've done bits and pieces before like a service, brake pads and discs, small jobs like that with out much problems. The MAP sensor is an easy enough one I think, no idea where the boost control solenoid is and the alternator seems easy to get to although I'd be coming in at it from the top of the engine but I have nothing apart from a jack to get underneath.

All advice welcome!
 

·
Registered
Joined
·
6,242 Posts
To be honest if the battery has died, the alternator isn't charging, it's done the battery no good it might charge up but if you were having problems with it anyway I'd change both, just bad luck on it all going at 1 time. The boost control and map both went on mine at the same time, both are electronics and not really any way to test them other than by resistance, I'm taking it its a 1.7? If so the boost control is on the back of the engine block


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #6 ·
Was hoping they where all connected and by one of them going that's what wasaybe stopping the alternator charging the battery...

Yes i I have a 1.7 - what's your thoughts on me being able to change these parts? Or will I take it to a mechanic? I think I have the most expensive alternator that goes with this model of Astra! Around £300 + fitting cost
 

·
Registered
Joined
·
6,242 Posts
Battery is easy, map sensor is 1 bolt at the end of the manifold, boost is 2 10mm bolts but needs to be done from underneath, and just have to go easy on the 2 pipes incase the rip, alternator I'm not sure haven't done mine, iirc its £200 odds


Sent from my iPhone using Tapatalk
 
1 - 7 of 7 Posts
Top