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Engine light flashing after engine replacement

Posted: Sat Nov 30, 2013 11:57 pm
by Dark Diver
Ok, this is a follow-up to my engine replacement which started here : http://www.corsa-b.co.uk/forum/viewtopi ... 54&t=20695

Now the new engine X12XE is in the bay and I reconnected all hoses and connectors except for the cooling system because I wanted to check that the engine starts before reinstalling the radiator + water hoses + temperature sensors connectors.

When I turn the key on, the engine light starts flashing and EPS light (on the bottom of the RPM gauge) is on. Of course the engine doesn't start.

From what I read on forums, engine light flashing = immobiliser issue.
Before I switched the engine, the car was starting easily and everytime (but had other issues).
I still have the chip in the key.
The battery was disconnected during 1 year but I hope the immobiliser has non-volatile memory, right ?

And of course I have a new engine which came with its harness (2 big connectors near the LH side of the plenum).

Since this is a X12XE engine, and I have not (yet) an OP-COM, I can't read the errors code from the ECU (or please give me a trick that works with this engine).
BTW, I don't have the security code of the car because the vendor did not even know the code for the radio. But I know I can pay Opel to get this code.

So my questions:
  • - How can I read error codes on a X12XE engine with no OP-COM ?
    - Is it possible that the management units loose the association with the key chip when disconnecting the battery during 1 year ?
    - Is there another reason for the ECU to "forget" this association (and require a re-configuration) ?
    - What type of electronics is on the engine, behind the 2 big connectors near the plenum ? As I replaced the engine, maybe the new engine has electronics failure...?
    - Does engine light flashing could come from another problem ? Which ones ?Where do I have to investigate ? I checked all fuses and they are good.
I read on forums that immobiliser system cuts fuel pump and ignition.
I have ignition, I checked it. I even started the engine during 10 seconds or so by injecting fuel through the throttle body.
And the fuel pump seems to run as I have pressure in the fuel rail (I pushed the valve on the middle of the rail and some fuel spurt out).
Do I really have immobiliser issue ?

Please HELP !!!

Re: Engine light flashing after engine replacement

Posted: Sun Dec 01, 2013 12:08 am
by johnny
You could try a rolling start, it normally tricks the immobliser and lets it start, also connect the cooling system first if it starts with no water it could just kill the engine and you want all.sensors pluged in,

Eml flashing is only immobilser, was the battery disconnected for a year?

Is the car cranking from the key?

Re: Engine light flashing after engine replacement

Posted: Sun Dec 01, 2013 4:50 pm
by Dark Diver
Yes the car is cranking from the key, even with another key which has no chip inside.
I have the same result with the stock key (with the right chip) as with the copy of the key (with no chip at all).
I can try a rolling start but what would differ from cranking with the starter motor ? How does it tricks the immobiliser ?
And how does the immobiliser act ? On the injection only ? From my previous tests, it does not act neither on the starter motor, nor on the ignition, nor on the fuel pump I believe.

I did not yet connect the cooling system just for the first start. I will be easier to access the engine without the radiator/water hoses, if required.
It's very cold here, so no worry with the engine running a few seconds with no cooling system.

Yes the battery was disconnected for at least 1 year.

Re: Engine light flashing after engine replacement

Posted: Sun Dec 01, 2013 5:25 pm
by johnny
Rolling start is just an old trick dont know how it works but have done it myself and it works,

Have you put a multimeter on the battery?

Does it crank quickly ie the starter is turning it or is it just cranking as if low battery crank

Re: Engine light flashing after engine replacement

Posted: Sun Dec 01, 2013 10:02 pm
by Dark Diver
I tried the rolling start this afternoon but it didn't work. The EML continued flashing. Only the EPS light turned off.
My battery is new and fully charged. The starter turns fast. The engine starts a few seconds when I inject fuel manually by the TB.

It looks like the injection doesn't work but everything else seems OK. The immobiliser could be the culprit but I don't see why it doesn't recognize my key. Either it didn't like to be disconnected from the battery during 1 year or something went wrong when I reconnected the battery.

I'll try to get an OP-COM to get the fault codes.

Re: Engine light flashing after engine replacement

Posted: Sun Dec 01, 2013 10:47 pm
by johnny
That new battery could have been on a shelf for years, put the multimeter on it to be sure 11v wont always start the car,

Lift the back seat up and screw off the black cover, you might need a hammer and listen for the pump to see if it primes when ignition is on, theres also a pressure valve at the rail, covered by a black cap normally press it and if fuel sprays out fuel is fine

Then check for spark, easiest way is get an old ht lead and bare one end and stick it in the coilpack, reason for this is just check everuthing

Re: Engine light flashing after engine replacement

Posted: Sun Dec 01, 2013 11:57 pm
by Dark Diver
I didn't hear the pump (I had the back cover removed because I flushed the tank of the "old" gas before refilling) but I have pressure in the fuel rail and I already tested the valve. So I presume the pump is powered. I'll put a multimeter on the pump harness and have someone turn on the key.

When I turn the key on, I just hear a noise such as an electric motor in the engine bay, during less than 1 second. And I hear it again when I turn the key off.
And if I step on the accelerator before switching on, I don't hear it, and I hear it as soon as I release the pedal.
The sound comes from the area of the plenum. Any idea on what it is ?

The spark I tested it first and it's fine. And the engine starts when injecting fuel manually, so ignition is OK.

Re: Engine light flashing after engine replacement

Posted: Mon Dec 02, 2013 12:08 am
by johnny
Forgot to.mention, press the valve with ignition on then crank the motor then ignition off, back on and hit the valve again, if it sprays both times fuel is good, spark is good, starter is good, then just check the volts of battery before,during and after cranking, needs at least 14v to start

Re: Engine light flashing after engine replacement

Posted: Mon Dec 02, 2013 12:10 am
by andy w
Just looking in what ya sed has the fuel pump pipe fell off when ya refitted it. The pipe i mean is inside the tank or there could be a blockage in the pump

Re: Engine light flashing after engine replacement

Posted: Mon Dec 02, 2013 11:43 pm
by Dark Diver
Humm, maybe but my main concern is the EML flashing (well, the main issue is the engine not starting).

I'll try johnny's advice : press the valve while cranking, and check that fuel is sprayed. If so, it will confirm that the pump + pipe are OK and the issue is really the immobiliser which stops injection.


Thank you all for your help.