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Help with car issue (check engine light)
Dear all,
First post for a while. The last time I got some really useful help regarding a problem with my old Astra. I ended up getting someone to replace the EGR valve which fixed it.
This time, I had a problem with the car almost stalling on idle and being slow to accelerate. The diagnosis at the garage was throttle body. This was cleaned and now the engine idles properly. However, the check engine light is still on and the car is slow to accelerate (I think it's in limp mode but I'm no expert). I have an OBD code reader but it says there are no fault codes. I've also tried the throttle body relearn procedure whereby the battery is disconnected for 10 mins then the car is left to idle for 10-15 mins. The check engine light just comes straight back on and revs are still limited.
My uneducated guess is that I will probably have to have the throttle body replaced, but I thought i'd check in here to see whether there is anything obvious that i've missed or could try first?
The car is a 2009 astra estate diesel 1.7l and it's done 95K.
Thanks.
First post for a while. The last time I got some really useful help regarding a problem with my old Astra. I ended up getting someone to replace the EGR valve which fixed it.
This time, I had a problem with the car almost stalling on idle and being slow to accelerate. The diagnosis at the garage was throttle body. This was cleaned and now the engine idles properly. However, the check engine light is still on and the car is slow to accelerate (I think it's in limp mode but I'm no expert). I have an OBD code reader but it says there are no fault codes. I've also tried the throttle body relearn procedure whereby the battery is disconnected for 10 mins then the car is left to idle for 10-15 mins. The check engine light just comes straight back on and revs are still limited.
My uneducated guess is that I will probably have to have the throttle body replaced, but I thought i'd check in here to see whether there is anything obvious that i've missed or could try first?
The car is a 2009 astra estate diesel 1.7l and it's done 95K.
Thanks.
0
Comments
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If there is an engine management light on, there will be a fault code.
If the light is resetting with the engine/ignition being switched off and back on, the fault code might only show when it's lit on that drive cycle or it might store the code in a "pending" file.
Have you tried attaching your OBD reader and driving around or running the engine up until the EML comes on?
I suspect with it being a diesel and the EML keeps resetting with the ignition, it's a fuelling or air related code.
A turbo diesel that's repeatedly tripping into limp mode when ran/driven and then resetting when the engine/ignition is turned off and back on suggests it's detecting a fault under some sort of load or condition.
For example, the wastegate on the turbo might be seized or the wastegate actuator has a problem.
The car's ECU will at some point in the drive cycle detect a problematic manifold pressure sensor reading and throw a limp at that point.
As it's a diesel, I'm not sure what you mean by Throttle Body.
Diesels don't have them.0
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