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Broken down need a bit of help


cainhead
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Well my day just went down hill. Finally got the car back after having a new fuel system to go with the single turbo I fitted and the thing won't start and I'm stuck at the supermarket. Spoke to the mechanic who did the work and he suggested a few tests.

 

1 - unplug fuel pump and connect 12v source to see if pump is broken. Pump runs fine.

 

2 - check fuel pump ecu by doing the temporary 12v mod. Did this and now the fuel pump runs when key is in the on position and clicked immobiliser as normal

 

However car won't fire. Turns over fine.

 

The fuel pump is constantly running, would that flood the engine? Any ideas would be great. Fuel system is top feed rail with 1000 asnu injectors and fpr. AemV2 ecu if that makes a difference.

 

Not the best way to be spending my birthday. So cheers for any advice.

Edited by cainhead (see edit history)
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Did you have the aem remapped for the new fuel system ?

Yeah had it all done yesterday. Brake down guy was as helpful as he could be, but said technically he shouldn't touch it as it was modified. Also said they would not recover it as it was to low, so costing me £50 to get it privately moved 2 miles in the morning. Guy checked and the car had no spark. Check ECU and can't see anything pulled out disconnected.

 

Any help welcome,

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Nightmare - is it churning at all or nopt even trying? Is the immobilser definitely switching off? check conn to battery for it?

Turning fine and fuel pump is now working. I fixed one issue then another pops up straight away. Not sure how to disconnect the immobiliser to problem shoot that

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Take a couple of the spark plugs out and have a look at them. They may be flooded with fuel if the ECU hasn't been mapped for the new injectors. They could also be shorted out with soot if the engine is running too rich.

 

You can get a flooded engine cleared by cranking the engine over for a good few seconds with all of the spark plugs removed and (really important) both EFI fuses removed.

If you've got soot on the spark plugs, a once over with a wire brush will be enough to clean them.

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Take a couple of the spark plugs out and have a look at them. They may be flooded with fuel if the ECU hasn't been mapped for the new injectors. They could also be shorted out with soot if the engine is running too rich.

 

You can get a flooded engine cleared by cranking the engine over for a good few seconds with all of the spark plugs removed and (really important) both EFI fuses removed.

If you've got soot on the spark plugs, a once over with a wire brush will be enough to clean them.

 

Ecu was mapped with injectors so. Breakdown guy checked the current and there was no current going to the plugs. It's like the ecu isn't sending a signal, or immobiliser is somehow stopping it

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Turning fine and fuel pump is now working. I fixed one issue then another pops up straight away. Not sure how to disconnect the immobiliser to problem shoot that

 

When mine (immobiliser) had problems it was a dodgy connection to the battery, so when it wasn't connected properly it wouldn't start.

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When mine (immobiliser) had problems it was a dodgy connection to the battery, so when it wasn't connected properly it wouldn't start.

 

Did yours allow the engine to turn though when the connection was bad. My thoughts were that if it were the immobiliser it would be the connection that allows the spark but knowing which or where that is could be tricky.

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Can't help but thought I'd say Happy Birthday.

 

Cheers, wish it had finished as it started. Was really enjoying the car this afternoon. Missed my birthday dinner but ended with a tin of beans and a bottle of very good Californian red wine to ease the pain.

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Just had some new info, apparently whilst being mapped with the AEM yesterday it would not start and cam sensors had to be swapped around. Reading a bit more into it looks like that would stop a signal being sent to get a spark. Hoping that it's just the sensor.

 

On that note does anyone around the London/Surrey/Berks/hants way got a cam sensor I could borrow to test the car. There's beer in it for anyone who has. Cheers

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Could also be that your crank trigger/timing star has separated and won't be sending a crank signal to the ECU. Upside to this is that if the ECU doesn't get a crank signal it won't send fuel or spark I don't think. So your pump is probably just priming up to the rail and that's it. Apparently quite common with higher powered 2jz's. Whifbitz etc. sell welded ones that hold up better

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Could also be that your crank trigger/timing star has separated and won't be sending a crank signal to the ECU. Upside to this is that if the ECU doesn't get a crank signal it won't send fuel or spark I don't think. So your pump is probably just priming up to the rail and that's it. Apparently quite common with higher powered 2jz's. Whifbitz etc. sell welded ones that hold up better

 

Did read something about that on another thread. Any idea how you check that. Cheers

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Any decent garage with a `scope and the knowledge to effectively use it can test all the sensors capable of causing a no spark issue without any dismantling or swapping out.

 

My issue is that the car is now at home. Could I test the voltage with a multimeter. If so do you know what voltage im looking for and which pins on cam and crank sensors?

 

Cheers

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There was a thread on here not so long back, it showed the resistance of all the sensors (ohms) and what their values should and should not be which would show a knackered sensor, if i find it ill edit here.

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What ECU is on it? Will it show sensor outputs in the software?

 

Start by checking if one of the two terminals on all the 6 coil packs is showing 12 volts positive relative to engine ground.

 

The next step is a bit trickier and potentially dangerous, so let us know how that test goes first. Obviously check all plugs are secure to the two cam position sensors and the flying lead to the crank position sensor.

 

To help speed things along, the next test would need you to have a 12V test light with a low wattage bulb in it (like a pointed screwdriver with a light inside and a flying lead). LED ones are no good, and it needs to be a low current consumption incandescent bulb).

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What ECU is on it? Will it show sensor outputs in the software?

 

Start by checking if one of the two terminals on all the 6 coil packs is showing 12 volts positive relative to engine ground.

 

The next step is a bit trickier and potentially dangerous, so let us know how that test goes first. Obviously check all plugs are secure to the two cam position sensors and the flying lead to the crank position sensor.

 

To help speed things along, the next test would need you to have a 12V test light with a low wattage bulb in it (like a pointed screwdriver with a light inside and a flying lead). LED ones are no good, and it needs to be a low current consumption incandescent bulb).

 

Hi Chris, thanks for the reply. Off to check the plugs, wiring and sensors shortly. Do you know if its obvious which is positive on the terminals? Are you meaning run the negative probe to the chassis.

 

The second step might be a bit much for me at the moment but appreciate the advice. Will check the simple bits first.

 

Forgot to say ECU is AEM V2, but I dont have the leads/software?

 

Cheers

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Ignition on, remove each coil pack connector in turn, with your black (negative) meter probe grounded to clean engine metal check you see around 12V with the red meter probe on the battery + terminal. That shows you have the meter set right, and good ground found. Then, probe each termial in one coil connector, still with ignition on. One of the two should show 12V +, the other nothing, or virtually nothing at all. if all six show 12v + on the same terminal it shows you have an ignition feed to all six coil packs.

 

 

What the ecu does is ground the other terminal in sequence, at the right time, for the correct length of time, as the crank and cams rotate. Unless you have 12V + on one terminal it won' spark. unless the ecu is being triggered to ground each coil's OTHER terminal in the right sequence, you will have no spark. It's perfectly possible and safe to test the latter at home, but do the 12V + test first.

 

 

I would IMAGINE the AEM software could show each sensors output in real time, but as you say, you need the PC wire and the software. If it will do this it would be well worth getting the lead and software or trailering the car to whoever has it if things become complicated. You could isolate the problem very quickly given adequate software. I am not familiar with the AEM software, sorry.

Edited by Chris Wilson (see edit history)
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Ignition on, remove each coil pack connector in turn, with your black (negative) meter probe grounded to clean engine metal check you see around 12V with the red meter probe on the battery + terminal. That shows you have the meter set right, and good ground found. Then, probe each termial in one coil connector, still with ignition on. One of the two should show 12V +, the other nothing, or virtually nothing at all. if all six show 12v + on the same terminal it shows you have an ignition feed to all six coil packs.

 

 

What the ecu does is ground the other terminal in sequence, at the right time, for the correct length of time, as the crank and cams rotate. Unless you have 12V + on one terminal it won' spark. unless the ecu is being triggered to ground each coil's OTHER terminal in the right sequence, you will have no spark. It's perfectly possible and safe to test the latter at home, but do the 12V + test first.

 

 

I would IMAGINE the AEM software could show each sensors output in real time, but as you say, you need the PC wire and the software. If it will do this it would be well worth getting the lead and software or trailering the car to whoever has it if things become complicated. You could isolate the problem very quickly given adequate software. I am not familiar with the AEM software, sorry.

 

Thanks again for walking me through that, have just had a quick check on the sensors and all plugs are in wires look intact, apart from the front cam sensor orange wire a split in the sheath, however wire looks intact. Bit grubby inside the terminal. Manged to get the sensors out, will give them a clean, but do you know if you can test the sensors or their terminal. I used a multi-meter with the ignition ON, but didn't get anything.

 

Will try the plugs shortly.

 

Cheers

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The 2 cam sensors and the crank sensor are only giving a voltage (a sine wave) out when the engine cranks. at cranking speed the voltage out will be a low voltage pulse. A sensitive moving coil (needle type) multi meter may show a swing once per revolution on the cam sensors, and multiple pulses on the crank sensor, but i have nver tried checking them like that. All 3 are very reliable, and none have voltage going TO them. Can't you get the AEM lead and software? You really should have that....

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