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Re: Start map for BMW S14 needed

Posted: Mon Oct 24, 2016 2:36 pm
by Rob Stevens
Sounds like you have the injector relay wired incorrectly or are measuring the wrong side of the injector.
You will get continuity of sorts if the injectors are plugged in.
If you are getting continuity between ecu pin 8 (with the plug out) and both connectors on the injectors (with the injector out) you have a fault. But I suspect you are misreading your device and have all the injectors in?
Do continuity testing with the 12v supply turned off.

Re: Start map for BMW S14 needed

Posted: Mon Oct 24, 2016 4:33 pm
by stevieturbo
I really dont see how you'd ever get a 6v reading testing for power on injector wiring on a 12v powered car. Unless the cars battery is almost flat.

You havent added some resistors on the power supply to the injectors or something ?

Re: Start map for BMW S14 needed

Posted: Tue Oct 25, 2016 10:43 am
by lofstrom
Rob Stevens wrote:Sounds like you have the injector relay wired incorrectly or are measuring the wrong side of the injector.
You will get continuity of sorts if the injectors are plugged in.
If you are getting continuity between ecu pin 8 (with the plug out) and both connectors on the injectors (with the injector out) you have a fault. But I suspect you are misreading your device and have all the injectors in?
Do continuity testing with the 12v supply turned off.
All measurements were done on the injector connectors, i.e. with the injectors unplugged.

The continuity testing was done with battery disconnected (and on the wiring loom only, disconnected on both ends)

Re: Start map for BMW S14 needed

Posted: Tue Oct 25, 2016 10:44 am
by lofstrom
stevieturbo wrote:I really dont see how you'd ever get a 6v reading testing for power on injector wiring on a 12v powered car. Unless the cars battery is almost flat.

You havent added some resistors on the power supply to the injectors or something ?
Not that I am aware of

Re: Start map for BMW S14 needed

Posted: Tue Oct 25, 2016 12:49 pm
by stevieturbo
Very little of this thread makes any sense.

The chances of a wiring loom being so bad...are just unrealistic.

I honestly have to question the measurements that are being taken as they just make little sense. Whether the meter is faulty, or the person using the meter...

Exactly how are you measuring at the injector wiring that you see 6v ?

Re: Start map for BMW S14 needed

Posted: Thu Oct 27, 2016 2:17 pm
by lofstrom
stevieturbo wrote:Very little of this thread makes any sense.

The chances of a wiring loom being so bad...are just unrealistic.

I honestly have to question the measurements that are being taken as they just make little sense. Whether the meter is faulty, or the person using the meter...

Exactly how are you measuring at the injector wiring that you see 6v ?
Thank you for the pep talk. If you don't fancy this thread I suggest you spend your time elsewhere...

Re: Start map for BMW S14 needed

Posted: Thu Oct 27, 2016 2:22 pm
by lofstrom
For anyone else interested, I have now re-done the following steps:


- Unplugged all injector connectors, coil pack, TPS, coolant temp, inlet air temp and crank sensor
- Power on ECU and measuring voltage to injector connectors. This was 6v on all four connectors
- With ECU ground disconnected I got 12v on all injector connectors
- Re-checked with ECU ground connected directly to battery neg and again 6v on all injector connectors
- Disconnected ECU main harness connector, ECU ign and ECU ground (ECU 12v cable still connected but battery also disconnected)
- Checked connectivity between pin 8 in the ECU connector and the injector connectors 1 and 4: ok
- Checked connectivity between pin 9 in the ECU connector and the injector connectors 2 and 3: ok

I know it sounds strange, and I'm confused too but this were the results.

Re: Start map for BMW S14 needed

Posted: Thu Oct 27, 2016 2:41 pm
by stevieturbo
And I ask again.

EXACTLY how are you testing these ?

If you are testing between inj 12v and battery ground as you should...then there really is no possible way this can be 6v unless there is a HUGE wiring problem.

If you are testing with the probes between the 2 injector terminals...then you are testing incorrectly.

Hence the pep talk.

Re: Start map for BMW S14 needed

Posted: Thu Oct 27, 2016 3:41 pm
by Rob Stevens
Are you sure you are not powering the injectors through the coil of the main relay somehow? Did you install the relay/ is there one?

Can you verify that your wiring is anything like the DTA drawing and that you are not using some ballast resistor?

Re: Start map for BMW S14 needed

Posted: Fri Oct 28, 2016 2:25 am
by Rob Stevens
'I also tested the wiring loom with the use of the continuity function on my multimeter. I tested continuity between pin 8/9 on the ECU connector and the four injector connectors. I found out that I got signal between pin 8 and both pins in each of the four connectors. Same for pin 9. Isn't that strange?'

You said this before, has that changed? Were the injectors in then? Was the ecu connector in?
The above statement doesn't match your latest test, you suggest that say pin 8 is connected to all 8 injector connectors.