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Car won't start


Jake

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(VVTi, Single turbo, Motec M600 piggy-backed onto stock ECU)

 

My car had a flat battery so I put it on charge overnight. I charged the battery on the car rather than removing or disconnecting it, because I'm lazy and it was raining. When I went to move the car from the driveway to the road yesterday it took a few attempts to get it running and it sounded rough when it did start, like it wasn't running on all cylinders maybe.

 

Now I can't get it started at all. It turns over OK but hardly seems to fire at all. If I press the throttle pedal (which I don't usually do when starting a car) it doesn't feel right, seems like the first half of the throttle pedal travel isn't doing anything - but it only does that after I've pressed the pedal once, the first time it feels OK. Something to do with the VVTi's FBW throttle?

 

Any ideas? Could I have fried the ignitor pack by charging the battery still connected?

 

Any suggestions?

 

Thanks

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(VVTi, Single turbo, Motec M600 piggy-backed onto stock ECU)

 

My car had a flat battery so I put it on charge overnight. I charged the battery on the car rather than removing or disconnecting it, because I'm lazy and it was raining. When I went to move the car from the driveway to the road yesterday it took a few attempts to get it running and it sounded rough when it did start, like it wasn't running on all cylinders maybe.

 

Now I can't get it started at all. It turns over OK but hardly seems to fire at all. If I press the throttle pedal (which I don't usually do when starting a car) it doesn't feel right, seems like the first half of the throttle pedal travel isn't doing anything - but it only does that after I've pressed the pedal once, the first time it feels OK. Something to do with the VVTi's FBW throttle?

 

Any ideas? Could I have fried the ignitor pack by charging the battery still connected?

 

Any suggestions?

 

Thanks

 

Engine warning light on?

If you're pressing the pedal through 70% of it's travel before getting any response it's gone into safe mode. It's not a happy bunny :( I'm actually really surprised you have a standard DBW system though as I would have thought the change to a MoTeC would have seen your car switched to standard throttle....but that's another story...ahhh bums and talking of the MoTeC you probably haven't got a warning light have you becasue of that.

 

Take the plugs out and see if they are wet (soaked)...test the spark.

 

Take the feed pipe off the throttle and with just full electrics on see of the butterfly moves throughout the range of pedal travel (obviously using the Bit the cable is attaced to in the engine bay) if it moves then the throttle is working - but it's tripping out when you start the car because of something else.

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As you suspected I don't have a functioning MIL light because of the Motec.

Thinking about it, it probably doesn't have a FBW throttle, not sure though.

 

I tried resetting the stock ECU just now but when I tried to start the engine it turned over for a while and then did a massive backfire. I'll try the igniter pack from my other Supe first 'cos that's a five minute job. If no joy I'll take the plugs out. I wish taking the plugs out wasn't such a pain on these cars!

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If it is backfireing....

 

http://en.wikipedia.org/wiki/Back-fire

 

There are two types of backfire. One is an explosion in the engine's exhaust manifold or exhaust system, this is most correctly referred to as afterfire. The other is an explosion in the engine's intake manifold.

 

Backfire in an automobile engine typically results from various malfunctions related to the air to fuel ratio. Usually, backfiring occurs in carbureted engines that are running lean where the air fuel mixture has insufficient fuel. ("Running lean" is typically a sign of mal-adjusted carburetors or fuel injection where there is not enough fuel for the amount of air). Afterfire, occurs in engines that have an emission system malfunction (air injection system diverter valve), exhaust leak or unburnt fuel in a decatted exhaust system. When a driver shifts up and lets off the gas, the engine has a moment of running rich or with insufficient oxygen. This causes an incomplete burn which causes the fumes to explode in the exhaust system. The leak itself is the most dangerous aspect. Without it, the mixture would cool enough not to explode. A fuel injected engine may backfire if an intake leak is present (causing the engine to run lean), or a fuel injection component such as an air-flow sensor is defective.

 

Common causes of backfires are:

 

Timing – If car is distributor-less

Timing – If a two stroke engine is backfiring every other stroke.

Fuel pressure, fuel filter and pump – leaks and corrosion could cause lack of fuel during the fuel injection event.

Bad wiring in ignition – ..if car won't run for more than a few moments.

In older engines, backfiring may be considered normal. Backfire is rare in modern cars with fuel-injection and computer-controlled fuel mixtures.

 

Common causes of back fires in the intake manifold are bad spark timing, or incorrect (usually lean) fuel ratio.

 

When starting an engine, timing that is too advanced will fire the spark plug before the intake valve is closed. The flame front will travel back in to the intake manifold, igniting all of that air and fuel as well. The resulting explosion then travels out of the carburetor and air cleaner. A common air filter will allow the gases to escape, but will block the flame front. On many small marine engines, no air filter is used, but a screen is placed over the intake of the carburetor as a flame arrestor to prevent these flames from escaping the intake, and potentially igniting fuel, or fuel vapors in the enclosed sump or bilge of the boat and causing a fire or explosion. Improperly adjusted carburetors that create a lean condition during acceleration can cause the air fuel mixture to burn so slowly, that combustion is still taking place during the exhaust stroke, and even when the intake valve opens. The flame front can then travel up the intake and cause a backfire.

 

In drag racing, backfires in the intake usually result in the complete destruction of the intake manifold, the carburetors, blower, and sometimes engine.

 

Retrieved from "http://en.wikipedia.org/wiki/Back-fire"

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Check your fuel pressure. Sparks. Then move onto injectors and your earths...infact you could go for the Earth's first as they could have casue the battery issue....
Fuel pressure is showing normal on the aeromotive FPR gauge. I whipped #1 plug out (cos you can do that without arsing about with the coil packs) and it's wet and smells of petrol.

 

The ignitor pack swap is a no-go. They're different connectors on the pre-VVTi :(

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Fuel pressure is showing normal on the aeromotive FPR gauge. I whipped #1 plug out (cos you can do that without arsing about with the coil packs) and it's wet and smells of petrol.

 

The ignitor pack swap is a no-go. They're different connectors on the pre-VVTi :(

 

Yeah you've got wasted spark (double sparking)...which the pre-vvti didn't have.

 

Can you test for a spark? Disable the injectors/fuel pump and turn it over?

 

I'd still look at all the earths in that circuit. Ingnitor and Injection. Poor earths can cause bizzare issue's. Have you done anything to it recently (other than have the battery drain?).

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I assume that you have checked all of your fuses ?
I've checked the ones in the fusebox. Don't know where else to look really.

 

Can you test for a spark? Disable the injectors/fuel pump and turn it over?
Do I test for a spark by holding a connected plug against the cam cover and turning it over?

I'll do that when somebody else comes home, my arms aren't long enough to turn the key and be under the bonnet simultaneously :)

I'd still look at all the earths in that circuit. Ingnitor and Injection. Poor earths can cause bizzare issue's.
Not sure what I'm looking for when it comes to earths. I've checked about for loose connections but other than that...?

 

Have you done anything to it recently (other than have the battery drain?).
No. The car was running fine a week ago, the last time I drove it.

 

My money is still on a dodgy ignitor pack. Shame I can't think of anyone local with a VVTi I could test it on.

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I thought I'd had a bit of luck; the chap who bought my white VVTi said I could borrow the Igniter off that car for a day to test on mine, but sadly the car is at MkIVStore and Lucifer is reluctant to send it to me in case he needs it that day :(

 

Surely the owner has the last say?

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