Engine Electricals

[PMoreland]

Hi,

I've been having some problems with my Evo 6, it stuttered at a roundabout the other night then once I'd got back and parked up, it wouldn't start the morning after. It cranks but no start, no engine light is showing.

I've tried multiple engine OBD II scanners but can't seem to connect to the ECU, the bridging pins didn't work either. After checking with the multimeter there's ignition power to the coils and they seem to measure fine on resistance but no spark is being generated. I've been trying to diagnose and check the crank sensor, I can't seem to measure any resistance or voltage through the sensor so I'm making an assumption that this may be the cause of failure ???

I've stripped it down and the sensor seems all intact and without any visible damage. Has anyone tried to measure voltage through their sensor with any luck ? I'm trying +ve on red and both the blue and black as -ve connectors while cranking but no reading is measured. I want to be sure the sensors gone as funds are tight after only buying the car a few weeks ago.

Finally, I'm not sure if this is part of the problem but my Tein EDFC unit isn't showing any display when the ignition is on any more. It's in line fused to the ignition which hasn't blown, neither has the main ignition fuse blown. There is power to it but no display, surely it should come on when the ignition is on?

This cars beginning to stress me out

 

[Evo4TomB]

Think it's time to call a automotive electrician they are about £35 per hour

 

[Simon@NTS]

Sounds like you've lost power to the ecu, download a wiring diagram and test the feeds to the ecu

 

[PMoreland]

Thanks for advice, my next step was to call the auto electrician out if I can't find the problem myself. I've got the wiring diagrams so I'll try to fault find with the ECU first.

Cheers

 

[Simon@NTS]

Well we're here to help

 

[Simon@NTS]

Checked fuses?

 

[B6lee]

Check the little resistors on the rocker cover haven't come loose

 

[PMoreland]

Yeah I checked the fuses a few times, they all showed ok on the multimeter. There's power to the coilpack and crank sensor etc on ignition but no spark. I know in a previous life the ECU has been played with so I'll check for any loose connections and make sure it's got a good earth and power. I've only just brought the car so electrical history is limited at the minute.

I have noticed that a previous owner had spliced out of the back of the OBD connector to by-pass the paper clip trick and bring up engine codes by connecting the two wires. This seems to be the only way I can get the engine light to flash, it shows no faults though which I'm not sure what to make of. Strangely the splice isn't taken out of pin one, I'll check tomorrow but I'm sure it's on the opposite end of the plug.

 

[GG205rob]

If i remember rightly pin 1 is bottom right as you look at the plug, not top left as you would expect.

 

[PMoreland]

There's number's stamped on the front of the plug, whether or not they correspond to what their supposed to be is a different matter. I think it it has been spliced into the bottom right so you may be onto something.

I'll also check the little resistors on the rocker cover tomorrow.

Hopefully I'll have her running again soon as the few days It was I've never had so much fun!

Cheers

 

[PMoreland]

Sounds like you've lost power to the ecu, download a wiring diagram and test the feeds to the ecu

Just checked the power feed to the ECU, there's roughly 12v at the battery and with the ignition on I'm getting 0.7 from both live feeds to the ECU. This can't be correct? I'm making a guess that there may be short out somewhere causing a drop in power?

 

[Simon@NTS]

Sound like your missing the feeds

 

[Simon@NTS]

I'd be disconnecting the ecu plug and checking continuity to ground

 

[PMoreland]

I've just checked for continuity at the plug on both the ground wires and they seemed fine buzzing away. What's your thought's on the 0.7 +ve feed at the plug?

 

[Simon@NTS]

Put one end in the feed and the other to ground and see what the meter says

 

[Simon@NTS]

Resistance with all plugs disconnected from ECM

 

[Simon@NTS]

What Evo is it by the way?

 

[evo arm's m7960]

this might help ?


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[PMoreland]

It's an Evo 6 GSR running (was) with the Apexi AVC type-R boost controller.

I've checked for continuity between +ve and ground and there was no beep. Checking for resistance read 9.24ohm (20k)

Cheers for you help again

 

[evo arm's m7960]

or this :O)

http://www.evoscan.com/manuals/Evo6/Workshop Manual/EV6_XEWiringCon.pdf


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