Advice? 2007 DB9 cranking but not starting, no code.

Advice? 2007 DB9 cranking but not starting, no code.



Original Poster:

30 posts

34 months

Wednesday 3rd May 2017
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Thanks for your attention,

2007 manual DB9 with 40,000miles, well maintained by independent shop. Everything electrical appears to operate normally, the engine cranks over vigorously, but the engine will not fire up and start. I return ignition back to OFF and try again, the status display runs through it's "checking" routine and comes up with no codes. Try starting and it's the same thing; it cranks over but not firing.

My 2007 DB9 went dead on me this week after I parked it in the garage and forgot to turn the ignition switch completely off.
The battery went dead, but I used the (+) terminal under the bonnet and the alternator bracket for a (-) and recharged it with a battery charger. Now it behaves like it's all charged up, except for not starting.

- I searched here for "dead battery" threads, and "not starting" threads and nothing quite matches my situation. There was one thread about a yellow battery reset switch under the seat, but that was a situation where everything electrical was dead after a depleted battery.

- Status Display: The status display shows no trouble codes (other than the seasonal "Regular Service Required" which came up last week).

- Spark plugs/coilpacks; I cannot get to them to see if there is spark to the engine. Is there another way to check?

- Fuel/mixture; I'll check the throttle bodies and see if I can detect whether they are actuating, but I got a code on these once before and cleaned their actuators. It was a far more graceful failure and I'd expect a Code.

- Fuses: I'm going to check all fuses, haven't gotten to that yet.

- ECU: I would think a fried ECU would show a Code..?

Has anything like this this happened to anyone here?
- Art


1 posts

4 months

Wednesday 11th July
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Got exactly the same with a db9 I have at the moment. Replaced trans oil cooler and pipes, road tested, parked up and now won't start. Did you get to the bottom of your fault?


503 posts

145 months

Wednesday 11th July
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had similar with my vantage, try a jump pack straight to the battery under the seat, or jump leads.


1,631 posts

133 months

Wednesday 11th July
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Pull back the rubber hoses from the throttle bodies and squirt some easy start down into the throttles. push the hoses back on and crank it over. If it tries to fire irratically, then your problem is fuel supply.
You could also try locking and unlocking the car to see if it is the immobiliser messing about. Have you tried another spare key?
You could also try cranking at 3/4 throttle in case you have flooded it.