Astra H 1.7CDTI engine woe, think the head is done
Discussion
Hi all,
I've been trying to diagnose if the head was on it's way out and I returned to the car to find that I can't start it. I checked the starter motor but I still ordered another and have replaced it with a new one.
I have 13v on the batt a vDrop of 0.63mA over it and that's not much more than it should be. With the new starter motor it really struggles to turn the engine over with a large dead spot and then it frees for a moment and hits the dead spot again, plus a strong scent that the starter motor is getting a kicking. So I'm not trying it again.
Prior to this, I had suspected that the head was going or also that the radiator was blocked, but when I went to test the radiator I couldn't start it up. Just a black out from the electrics and a reset after trying to start up.
I also manually turned/cranked the crank/pistons over and they are free, I'm not a mechanic but I know a little bit.
Is it that something in the head has broken when when being parked up for a few days and on trying to start again it's now jammed? Seems odd but it's a car and they can be wierd.
Fault codes - (Are these right?)
007071 - Ambient Air Temperature Sensor Malfunction B-016 (Only fixed it a moment ago as the wires snapped.
210870 -
050074 - speed/throttle codes 0500 ignorable
05007F -
050076 -
None of them point to a fault.
Thank you
I've been trying to diagnose if the head was on it's way out and I returned to the car to find that I can't start it. I checked the starter motor but I still ordered another and have replaced it with a new one.
I have 13v on the batt a vDrop of 0.63mA over it and that's not much more than it should be. With the new starter motor it really struggles to turn the engine over with a large dead spot and then it frees for a moment and hits the dead spot again, plus a strong scent that the starter motor is getting a kicking. So I'm not trying it again.
Prior to this, I had suspected that the head was going or also that the radiator was blocked, but when I went to test the radiator I couldn't start it up. Just a black out from the electrics and a reset after trying to start up.
I also manually turned/cranked the crank/pistons over and they are free, I'm not a mechanic but I know a little bit.
Is it that something in the head has broken when when being parked up for a few days and on trying to start again it's now jammed? Seems odd but it's a car and they can be wierd.
Fault codes - (Are these right?)
007071 - Ambient Air Temperature Sensor Malfunction B-016 (Only fixed it a moment ago as the wires snapped.
210870 -
050074 - speed/throttle codes 0500 ignorable
05007F -
050076 -
None of them point to a fault.
Thank you
Edited by PistolRunner on Sunday 21st December 19:57
First off, and as always.
Some history ?
Did whatever problem there is just suddenly happen ? Anything prior to it ?
And volt drop would be measured in....volts. Not mA
And when you say 13v...is this with engine running or stopped, as if stopped, 13v would be rather unusual and high.
What is voltage at battery when cranking ?
Are all wiring connectors to both starter, and ground from battery to chassis/engine all good ?
Some history ?
Did whatever problem there is just suddenly happen ? Anything prior to it ?
And volt drop would be measured in....volts. Not mA
And when you say 13v...is this with engine running or stopped, as if stopped, 13v would be rather unusual and high.
What is voltage at battery when cranking ?
Are all wiring connectors to both starter, and ground from battery to chassis/engine all good ?
The first sign was that one pipe burst and after I replaced that another went the same day. After I replaced that the water pump developed a leak.
You're right about the vdrop as it's the current when off. The voltage on the battery is due to charging.
After the water pump was replaced the expansion tank started showing signs of too much pressure as it leaked steam. I tested the radiator at the beginning of this and it was OK though after parking up after having the water pump fitted it wouldn't start as described at the opening of this query.
I can't see any damage or corrosion to the cables and when cranking the voltage simply dies. As I've said it's as if it's shorting out but nothing is, only the voltage drops so low and returned after ceasing to crank it for starting up.
Saying all of that I have manually turned the engine over and it turns, so how would the head not turn the normal way if you use the key?
You're right about the vdrop as it's the current when off. The voltage on the battery is due to charging.
After the water pump was replaced the expansion tank started showing signs of too much pressure as it leaked steam. I tested the radiator at the beginning of this and it was OK though after parking up after having the water pump fitted it wouldn't start as described at the opening of this query.
I can't see any damage or corrosion to the cables and when cranking the voltage simply dies. As I've said it's as if it's shorting out but nothing is, only the voltage drops so low and returned after ceasing to crank it for starting up.
Saying all of that I have manually turned the engine over and it turns, so how would the head not turn the normal way if you use the key?
PistolRunner said:
The first sign was that one pipe burst and after I replaced that another went the same day. After I replaced that the water pump developed a leak.
You're right about the vdrop as it's the current when off. The voltage on the battery is due to charging.
After the water pump was replaced the expansion tank started showing signs of too much pressure as it leaked steam. I tested the radiator at the beginning of this and it was OK though after parking up after having the water pump fitted it wouldn't start as described at the opening of this query.
I can't see any damage or corrosion to the cables and when cranking the voltage simply dies. As I've said it's as if it's shorting out but nothing is, only the voltage drops so low and returned after ceasing to crank it for starting up.
Saying all of that I have manually turned the engine over and it turns, so how would the head not turn the normal way if you use the key?
So what you seem to be trying to say is there are signs of excessive pressure within the cooling system ? Measuring how much would offer some help, or doing either a CO or litmus type test to see if there is any combustion gasses present would also help.You're right about the vdrop as it's the current when off. The voltage on the battery is due to charging.
After the water pump was replaced the expansion tank started showing signs of too much pressure as it leaked steam. I tested the radiator at the beginning of this and it was OK though after parking up after having the water pump fitted it wouldn't start as described at the opening of this query.
I can't see any damage or corrosion to the cables and when cranking the voltage simply dies. As I've said it's as if it's shorting out but nothing is, only the voltage drops so low and returned after ceasing to crank it for starting up.
Saying all of that I have manually turned the engine over and it turns, so how would the head not turn the normal way if you use the key?
Generally these engines are very reliable as far as heads etc go though, but that isnt to say there isnt a head or head gasket related problem. Again, do some tests to get some useful info.
Measuring voltage with a charger on the battery....is strange to say the least.
Answer the question, what is voltage at the battery during cranking ?
Because your vague answer just sounds like a flat battery, or poor connection to the starter.
As to how would it not turn over on key if it will by hand ? see above statement about flat battery.
Sounds like a possable H/G to me and now it's hydrolocking ??
Buttoned up (finished the job off) a 54 plate 1.7 Td astra this moring, that did the same, not turning over a few hours later unless you released the pressure in the cooling system at the end of the prev drive, this was the end of a series of events, the first was blowing a hose, then the side out the rad.
Buttoned up (finished the job off) a 54 plate 1.7 Td astra this moring, that did the same, not turning over a few hours later unless you released the pressure in the cooling system at the end of the prev drive, this was the end of a series of events, the first was blowing a hose, then the side out the rad.
Before you start tearing it apart get a sniffer test carried out, it won't cost much and you will have a proper diagnosis.
Head gaskets aren't hard to do on these and you can lock the pump and cam pulleys with bolts which makes timing belt installation simpler although IIRC getting everything lined up involves turning the crank a number times before the marks line up.
Head gaskets aren't hard to do on these and you can lock the pump and cam pulleys with bolts which makes timing belt installation simpler although IIRC getting everything lined up involves turning the crank a number times before the marks line up.
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