P38A starting problem after overheat P38 4.6 2001 Vouge

Hi after completing 2000 miles since a top engine rebuild ( head gaskets due to a blow to atmosphere only). I was towing a transporter trailer on a 96 mile round journey, having unloaded was on my return trip at about 58 miles when the engine overheated I stopped within 500 mtrs. We let her cool down and added 3/4 of a ltr of water the engine started and ran fine. however after running on tick over for five minuets she stalled or I should say stopped. hasn't run since.
I have a Hawkeye Total and the reading from the first list showed various cylinders misfiring. I have cleared those faults. there are no faults showing now. I have a syncmate for this vehicle so becm is connecting to engine, and showing no faults on dashboard readout. Keycode is OK.
All door footwell plugs have been removed and soldered connections made (last year ran well afterwards), also have cleaned multi pin connector under the expansion tank.
The vehicle has no spark, checked with plug no 1 earth to engine block. The coil pack was re-sited behind the battery box when the heads were done last March so has not suffered from heat from the overheat.
Anyone have an ideas where I should look next.
Vehicle based in Sussex UK.

If ignore the overheat for now and check the basics, fuses, relays and fusebox

Fuse box already checked.but to rule it out I have cleaned each Fuse, checked for continuity and sprayed each one with contact cleaner. Also removed Fuse box under bonnet and removed plugs sprayed clean with contact cleaner . Still no start. Smell petrol and can hear compression but no spark.

what about the relays? if you're not sure then swap them round with others of the same colour, R15 I think is for ignition

Sorry all relays checked and sprayed clean swapped with a windscreen wiper relay wipers working still no start

Swapped ignition relay with windscreen wiper relay. Sorry reply not clear.

Do you have power to coil packs?
CPS? Gone kurput after getting too hot maybe.

J

As in opening question coil packs not attached to heads, they are now housed behind the battery. I have check new cables are ok.

Does everything else work?

J

CPS are not attached to the heads. Now housed behind battery, so did not get hot,as stated in opening question

Seams to wor ok engine management light remains on dash board when ign switch on.

steve6621 said:

As in opening question coil packs not attached to heads, they are now housed behind the battery. I have check new cables are ok.

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Do they have power?

steve6621 said:

CPS are not attached to the heads. Now housed behind battery, so did not get hot,as stated in opening question

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Crank Position Sensor it is a single point failure.

which cylinders showed misfire?

J

Ignition Coils (Z261)
The electronic ignition system is fitted with two quad coil packs, which are directly driven by the Electronic Control Module (ECM) (Z132) and operates using the ‘wasted spark’ principle. Each coil pack contains two ignition coils. The circuit to each coil is completed via switching within the ECM (A132), allowing the coil to charge up and then fire. It produces sparks in two cylinders simultaneously, one cylinder on the compression stroke and one on the exhaust stroke.
Coil pack 1 feeds cylinders 2, 3, 5 and 8.
Coil pack 2 feeds cylinders 1, 6, 4 and 7.
The resistance of the spark plug in the compression stroke is higher than that in the exhaust stroke and hence more spark energy is dissipated in the compression stroke.
Coil failure will result in a lack of ignition, which may result in an engine misfire in the related cylinder(s). An engine misfire is indicated by the illumination of the Malfunction Indicator Lamp (MIL)


From Manual.
Note last line.
J

Crank sensor taken off, checked replaced with a working one. Old one checked on bench found to be ok.
Cylinders showing misfires not noted. But from memory 3,4,6,7.

Thanks Marjon I have rave manual I know how they work. Can you tell me how to test for power to them without damaging the system or my volt meter?

steve6621 said:

Thanks Marjon I have rave manual I know how they work. Can you tell me how to test for power to them without damaging the system or my volt meter?

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just stick your tongue out for a moment sir, this won't hurt a bit....honest!

So have you check sparks on all cylinders?

steve6621 said:

Crank sensor taken off, checked replaced with a working one. Old one checked on bench found to be ok.
Cylinders showing misfires not noted. But from memory 3,4,6,7.

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steve6621 said:

Thanks Marjon I have rave manual I know how they work. Can you tell me how to test for power to them without damaging the system or my volt meter?

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probe the lead at the coil packs and see if you have 12v.


Ignition Coil Relay
The ignition coil relay is controlled by the Body electrical Control Module (BeCM). The BeCM receives conformation from the anti–theft immobiliser that an approved ignition key has been inserted. On approval, the BeCM will provide a ground to the ignition coil relay.
When the ignition switch is turned from position 0 to position II and an approved ignition key is inserted a power supply is sent to the ignition coils, evaporative emission canister purge valve and heated oxygen sensor (HO2S). When the ignition is switched off, power supply to the ignition coils, evaporative emission canister purge valve and HO2S is cut immediately.

From manual.

J

Or...

Probed leads too CPS no power, tested ignition on and cranking.
Tested CPS have ohms readings

steve6621 said:

Probed leads too CPS no power, tested ignition on and cranking.
Tested CPS have ohms readings

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So are you thinking CPS is coil packs?
It is Crank Position Sensor.
I think this needs to be cleared up.
sorry but it’s confusing me now what you have tested.

J