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Starting the engine for the first time


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Posted

No I am not using throttle bodies.

Posted

The ECU send signal ( usually -ve) either directly to pump or via a relay. Initially it primes and then pumps on cranking or when running

You could disconnect the fuel line to the carbs and make sure you have fuel being delivered. If not the you need to use a multimeter to trace wiring and feed to fuel pump 

If you have an inertia switch fitted to the car you need to make sure the red button is pushed in and activating the power supply to the pump 

Posted

Have you got individual throttle bodies, (look a bit like a pair of Weber carbs on the side of the engine).

Is it an Omex ecu?

Are ALL the engine sensors connected to the ecu, you should have:

Throttle position sensor (TPS)

Crank position sensor (CPS)

Cam position sensor - not all Westfield installations use it, but if yours is one, it MUST be present.

Lambda sensor - again, only used on more modern engines, but if needed on your engine, must be present.

Water temperature sensor

Air temperature sensor

The last two aren't strictly necessary on some ecu's but can cause issues if not present.

Most of those sensors won't stop it attempting to fire, but may prevent it running properly. However the crank and/or cam sensor will absolutely stop the engine from firing if not connected, or if the ecu isn't picking up a signal from them.

With pretty much all the aftermarket ecu's Westfield have used over the years, when you first turn the ignition key to the ignition on position, the ecu will turn on the fuel pump for two or three seconds to prime the fuel lines. It will then turn it off again. There is enough fuel "stored" in the lines for the engine to fire, as soon as the engine fires the revs will increase, which the CPS detects and turns the fuel pump back on.

If you have an inertia switch at the rear of the car to kill the pump in an accident, press the reset button and make sure it hasn't been accidentally tripped during the build.

PS, What engine is it?

Posted

Ah, just spotted yours and Tels post!

Carbs make it simpler!

Posted

In that case you will probably just have a crank sensor and maybe TPS along with water and possibly air temp sensors.

Posted

Thanks for the responses. The engine is a 2 litre Zetec with an Omex ecu. I ​thought that I had plugged everything but I will check again tomorrow. I will also get a multi-meter on the fuel pump to check that it is priming the fuel lines.

Posted

Thanks for the responses. The engine is a 2 litre Zetec with an Omex ecu. I ​thought that I had plugged everything but I will check again tomorrow. I will also get a multi-meter on the fuel pump to check that it is priming the fuel lines.

You should hear it ticking away.

Posted

Ah right.... check out the sensors and what has been suggested.

As you think it's the pump I'd start there. The fuel sensor has no effect on the ecu that I'm aware of.

Check it has 12v when you first turn it on. Then if not work backwards. Checking the inertia switch if you have one and then the relay that the omex controls.

Posted

It's less common to have the fuel pump connected to the ecu on a carbs installation, and less common for an inertia switch to be used, so don't panic if you don't have them.

The carbs themselves have little float bowls that should fill with fuel, (if not already full) as soon as the ignition is turned on. You need to check that the carbs are getting fuel first.

Posted

Easiest war to check fuel is getting to carbs is to remove the fuel line to carbs and put tube end in a plastic bottle ....turn ignition on and petrol should flow ( also try when cranking engine over )

Also if it is not flowing check the fuse to the fuel pump has not blown

Posted

Checking anything with a multi-meter has been hampered by mine stopping working! I will pick up a replacement tomorrow. I suspect that the ECU may not be getting any power but it's hard to check without a multi-meter!

Posted

Okay so I have a working multimeter now.

 

The chassis earth connections to the ECU are fine (5A and 7B on the ECU connector) but I have no 12V on pin 4A :(

 

Where does the red wire on pin 4A come from?

 

Thanks,

Simon.

Posted

Red wire on omex ecu is the supply in should be 1amp fused which comes from a power relay usually

Posted

If I remember rightly my onex600 has 2 power lines a small 1 or two amp line and a switched live from the ignition key. I'd have to find the wiring get diagram to be sure

  • 3 weeks later...
Posted

Well at the fourth attempt I now have a car with a running engine!

 

Attempt 1 - Wires to fuel pump not connected! :blush:

Attempt 2 - No power to ECU - Forgot one connection! :blush:

Attempt 3 - Battery needs charging :(

Attempt 4 - Success! :)

 

It feels like a massive milestone being a complete novice in this area. Looking forward to escaping my single garage and finishing the build in the sunshine!

 

Simon.

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