Page 1 of 1

325 wont start

Posted: Sun Dec 19, 2010 11:32 am
by Pyros
had my 325 project for a while now, the engine was running but went to start it the other day and it turns over but does not fire, i have been working on the wiring and i am pretty sure it is all correct, the fuel pump does not prime on the ignition and only runs if i take out the pump relay and bridge two of the pins, but even then after priming the engine it still does not fire, i have fuel going into the rail and sparks and airflow, so i am at a loss, does anyone have any ideas? and if anyone would like to come and help me for a day to get this running, as my parents are thinking of moving and it is in there garage, i would be so gratefull.

Re: 325 wont start

Posted: Sun Dec 19, 2010 11:42 am
by eltel
check the multiplug under the inlet manifold, wiggle it with someone trying to start the car.
if the pump does not work how have you got fuel at the rail??
what wiring have you worked on and why??

Re: 325 wont start

Posted: Sun Dec 19, 2010 11:44 am
by eltel
how long was kit stood?? could the fuel have gone off??

Re: 325 wont start

Posted: Sun Dec 19, 2010 11:47 am
by kerrie
Check spark plugs if they are wet then it is a spark problem if they are dry then it is a fuel problem, Alarms usually cut the fuel did you work on that wiring?

Re: 325 wont start

Posted: Sun Dec 19, 2010 11:47 am
by Pyros
i can get the pump to run by bridging two of the pins on the relay housing when i take the fuel pump relay out, its a conversion jobby 318i tourer into a 325 pick up truck, i know its not to everyone taste but i like it, the only problem is that i bought it half done but they left all the wiring in the car even for the rear doors so i started cleaning the wiring up, wish i had not done it now

Re: 325 wont start

Posted: Sun Dec 19, 2010 11:49 am
by Pyros
Kerrie the sparks are working there was an alarm in the car but that was bypassed when i first got it, now ive taken the whole kit out, but i have not come across any breaks in wires where the alarm was

Re: 325 wont start

Posted: Sun Dec 19, 2010 12:35 pm
by eltel
you need to check all the values at the ecu and sensors are correct. have a browse through the motronic blog on the top of this forum and do some searches on the ecu, i am sure brianmoooore has commented about the pin values and locations etc.

Re: 325 wont start

Posted: Sun Dec 19, 2010 12:59 pm
by kerrie
If I remember correctly the 325 cannot just plug and play with the c101 plug 2 wires are incorrect, and I think one of them is the feul pump trigger, PM Brian moore he is a wiz, or check the M50 318 swap threads for info

Re: 325 wont start

Posted: Sun Dec 19, 2010 3:01 pm
by Brianmoooore
kerrie wrote:If I remember correctly the 325 cannot just plug and play with the c101 plug 2 wires are incorrect, and I think one of them is the feul pump trigger, PM Brian moore he is a wiz, or check the M50 318 swap threads for info
It's a M30 conversion you're thinking of. M20B25 into a 318i is plug and play, apart from some minor possible complications concerning the power feed to the ABS brake electrics - either the ABS doesn't work, with the light on, or the engine and body loom go up in smoke.
First thing to do is check whether any spark plug sparks once every two turns of the crankshaft.

Re: 325 wont start

Posted: Sun Dec 19, 2010 5:58 pm
by Pyros
the sparks are sparking once every two turns

Re: 325 wont start

Posted: Sun Dec 19, 2010 8:08 pm
by Brianmoooore
Are they dry or wet with fuel after a cranking session?

Re: 325 wont start

Posted: Sun Dec 19, 2010 8:13 pm
by Pyros
they looked wet, but not drenched

Re: 325 wont start

Posted: Sun Dec 19, 2010 9:16 pm
by Brianmoooore
Pyros wrote:they looked wet, but not drenched
Mmmm! How wet is wet? I suppose that if they're not drenched we can probably assume that the reason it's not running isn't because the mixture is excessively rich, and, by virtue of the fact that it has sparks, and isn't running, that the mixture is excessively weak.
Any work been done on the car since it ran?
Any chance the fuel pipes are the wrong way around?
Check out the plug and socket under the inlet manifold, where the injector loom joins the main engine loom. Especially check under the rubber boot of the lower half - it's quite common to find corroded wires here, as the boot is a water trap.

Re: 325 wont start

Posted: Sun Dec 19, 2010 10:50 pm
by Pyros
okay will check that tomorrow

Re: 325 wont start

Posted: Sun Dec 19, 2010 10:58 pm
by Brianmoooore
There's also one other thing you could try at this point. Any access to a source of propane or butane?

Re: 325 wont start

Posted: Sun Dec 19, 2010 11:02 pm
by Pyros
that can be arranged i think

Re: 325 wont start

Posted: Sun Dec 19, 2010 11:12 pm
by Brianmoooore
Remove the air hose to the throttle body, and fuse 11 (to disable the petrol system), and crank the engine while releasing propane gas into the mouth of the throttle body while you crank it with the throttle partly open. If you have sparks, and nothing seriously mechanically wrong with the engine, such as bent valves or a broken cam belt, it should start and run.
I use a high pressure propane blowlamp for this (runs of off a 3.9kg red bottle), with the burner shroud and jet removed.

Re: 325 wont start

Posted: Sun Feb 08, 2015 8:37 pm
by Bert318
As a matter of interest did you ever get this sorted?