Vauxhall Astra Running Problem

[Spudhaynes]

Hi All i am new to this but i thought i would give it a go i have bought a Astra estate with a blown engine i have replaced the engine with a recon unit.
Now i have a spanner lamp on after about i minute of running and the engine wont rev above 4000 RPM
I have tried a new cam sensor but no good by the way there are no codes stored.

Hope some one can help

Spudhaynes

[Matt Seabrook]

What are you using to scan the car? If it's just a cheep OBD reader off the likes of eBay etc then you will not have manufacture specific codes and there may be more gained from a better code read.

[Crafty_]

What age is the car/engine and what engine code is it ?
Does the car run rough ? stall ? down on power ?

[N7GTX]

Spudhaynes said:

by the way there are no codes stored.

If the light has been on there WILL be a code or codes stored. Get it read with Tech 2 or Vaux-com (Op-com) and it will list the 'Present' and 'Not Present' codes. There will be at least one 'Not Present' for the light having been on.
Cheaper than parts darts....

[PaulKemp]

What engine?
On my Mondeo the injectors are coded to the ECU
If you change the engine and don't reprogram the ECU it won't run properly

[N7GTX]

Think he's gone A.W.O.L.

[Spudhaynes]

Hi all thanks for reply's i have cured the spanner light on on tick over i found broken wire on radiator switch but now the problem is it will not rev over 4000 rpm and then spanner light comes on.
I have checked with code reader and it comes up with crank sensor i have bought a new one but it will not start with new one fitted when i fit the original one back it fires and runs great but will not rev over 4000 rpm any ideas. I have also tried a second cam sensor.
Some one told me if there is no rpm signal it will use the cam signal to run may be the crank sensor is faulty and allowing the cam sensor to take over.Then when the new rpm sensor is fitted its not allowing it to run.

Ever hopeful Spud

Astra 55 plate z1.6xep Twinport

Sorry cant stay online for to long.

Edited by Spudhaynes on Wednesday 22 May 12:35

Edited by Spudhaynes on Wednesday 22 May 19:07

[Crafty_]

I think you need to find someone with tech2 so they can read live data and see whats going on.
I'd agree that crank sensor is the issue, the old XEV engine would do this when the crank sensor signal broke down - run off the cam, go to block injection and not rev.
The replacement crank sensor not working is curious. Could be a faulty part I guess.

Do you know if the crank fault code appeared before you fitted the new crank sensor ?

Either way it may be beneficial to clear the codes at this point, you need a code reader to do this, but if you are going to someone with tech2 they can do that.

Are you using the original engine loom or one that came with the replacement engine ? Can you check the harness for damage/breaks?

[Spudhaynes]

Hi Crafty thanks for that yes i am using the same engine loom the car came with and when i get back from a trip a mate is going to come round with tech 2 so then i hope to find fault.

[Disco_Biscuit]

Spudhaynes said:

Hi all thanks for reply's i have cured the spanner light on on tick over i found broken wire on radiator switch but now the problem is it will not rev over 4000 rpm and then spanner light comes on.
I have checked with code reader and it comes up with crank sensor i have bought a new one but it will not start with new one fitted when i fit the original one back it fires and runs great but will not rev over 4000 rpm any ideas. I have also tried a second cam sensor.
Some one told me if there is no rpm signal it will use the cam signal to run may be the crank sensor is faulty and allowing the cam sensor to take over.Then when the new rpm sensor is fitted its not allowing it to run.

Ever hopeful Spud

Astra 55 plate z1.6xep Twinport

Sorry cant stay online for to long.

Edited by Spudhaynes on Wednesday 22 May 12:35

Edited by Spudhaynes on Wednesday 22 May 19:07

Did you buy a Genuine Vauxhall sensor or a pattern one? if its a pattern part there's the problem

[Spudhaynes]

Hi there Disco yes it is a pattern sensor but i have a Vauxhall one as well and it does the same i have tried a second hand sensor and pattern sensor and a new vauxhall sensor plus a second cam sensor still the same .


Spudhaynes

[Spudhaynes]

Hi All still got problem with engine revving to 4000 and then bouncing code for crank sensor replaced sensor car will not start put old sensor back engine fires and runs to 4000 rpm checked wiring to sensor all ok continuity from brown wire at multi plug and grey wire at ecu plug good.
Is it possible to get the valve timing 180 out as i don't think this is the case but cam belt timing was done by engine rebuild company.

Any advice gratefully received

Spudhaynes

[PaulKemp]

I'd check wires from/to sensor
Both crank and cam

[Spudhaynes]

Hi all still got the problem with the Astra i have been to a Vauxhall dealer and tech 2 says crank shaft sensor out of range this happens at 4000rpm have checked the sensor pick up all seems ok but when the pick up point on the ring is in site of sensor hole the crank pully is not at tdc is this correct as i thought it should be at TDC.
Also when new sensor fitted it starts and dies if i fit old sensor it starts and runs ok but will not rev above 4000 rpm.

Getting very frustrated now

please any help or ideas would be great

spudhaynes

[Crafty_]

Hmm thats interesting, I think it should be at TDC.

But, why does it cause a problem at 4000rpm and not on crank ?

I once saw an engine where the crank disc had been dropped, much like yours everything seemed to be fine but refused to fire. After a fair bit of head scratching it was decided the crank disc had been damaged. It was duly changed and the old one was indeed slightly bent.
With a good disc the engine fired and ran perfectly.

I wonder if the crank has excessive end float that is causing the disc to move and go out of spec ? or something like that ?

Have asked a mate in the know about positioning of the missing teeth on the crank disc relative to TDC.

Edited by Crafty_ on Friday 7th June 20:41

[Crafty_]

What is the code you are getting P03xx - whats the xx ?

I asked a mate and he said:

If you get a crank sensor fault it will usually have a code like P03xx and its the xx that gives the clues.
It could be cam timing out, if it's not it could be cam belt too loose / tight or crank / cam signal out from one another.
It could also be that interference in the engine bay is affecting the crank / cam signal and the ecu does the damage limit rpm thing.
There are too many possibilities without seeing the car or having a bit more info.

The missing teeth are about 60 degrees before tdc

[PoleDriver]

Probably your old sensor is knackered and not giving output so car runs on crank sensor.
Putting a new working sensor in is highlighting the fact that something is wrong with timing setup from the new sensor and preventing the engine from ruining itself??

[Spudhaynes]

Thanks crafty the info about missing teeth on ring was what i am trying to find out so the 60% is about right so now i will speak to engine builders to find out if they replaced ring or if i drop sump will it effect my three month warranty. then i can look for damage.

Regards Spudhaynes

[Matt Seabrook]

Missing teeth are normally well before TDC on most engines as this is where crank speed is most stable. Crank velocity at TDC is not so predictable and as used for timing is no good at TDC. HTH

[Crafty_]

Spudhaynes said:

Thanks crafty the info about missing teeth on ring was what i am trying to find out so the 60% is about right so now i will speak to engine builders to find out if they replaced ring or if i drop sump will it effect my three month warranty. then i can look for damage.

Regards Spudhaynes

Check the timing marks on the cam pulleys first, should be a little groove and some mark on the cam cover that they line up with.

Alternatively take it to the engine builders and asked them what they messed up