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ropeman
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Wed Sep 06, 2006 11:59 am

My 325 always starts - well it has so far, but it's not 100%

When I turn the key it just seems to turn the engine over, if I let go of the key key 9 times out of 10 it starts at this point, and there's a faint smell of fuel for a couple of seconds.

If it doesn't start like this then the second time it usually does the same thing and starts or it just fires straight up as it should.

My guess is it's getting to much fuel at the ignition stage? Any ideas what would be causing this and how to fix it? Cheers
Globulator
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Wed Sep 06, 2006 2:27 pm

It sounds like you may benefit from a new battery - i.e. the spark is much bigger when the battery is unloaded.

The fuel smell could just be flooding due to not starting - if you start most injection cars they just keep tipping the fuel in until they start. In this case use a bit of throttle while you start (to lean off the mixture) and back off as soon as she fires.

Personally I'd go for the new battery and check the earthing of battery, engine and coil is good too.
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ropeman
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Wed Sep 06, 2006 2:37 pm

Don't think it's the battery, it's only a month old. Along with new leads, plugs and coil :? Should have metioned that before...... sorry

Any other ideas.
ropeman
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Thu Sep 07, 2006 10:56 am

Any other ideas?
Globulator
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Thu Sep 07, 2006 11:31 am

Hmmm - not really!

You might still try diagnosing it further by starting it with a little throttle - to see if it is trying to start too rich. You could have fuel seepage from the injectors when the pressure is held in the fuel rail after switch-off, and this is upsetting it.

I'm not sure of an easy way of testing for seepage though.
1986 325i 'vert, funk louder than standard.
"No Mr Bond, I expect you to tell me why your 4 litre, 282bhp sports car can't outrun some lardy old Mercs.."
Audio & electronic software: http://www.cutestudio.net
ropeman
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Thu Sep 07, 2006 11:56 am

Cool, I'll do a bit of investigation and report back :)
ropeman
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Thu Sep 07, 2006 11:46 pm

Right, a bit more to report. Starting with or without throttle gets the same results ie. it's quite slow to start and when it does it kind of splutters into action. Once running it's 100%.

If I start it switch it off again and re-start it fires up as it should (turns 3 times and fires).
massive
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Fri Sep 08, 2006 3:34 am

maybe the round plug under the inlet is corroded. I'm told its a common problem on E30's and can cause similar probs to how you describe.
ropeman
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Fri Sep 08, 2006 9:21 am

massive wrote:maybe the round plug under the inlet is corroded. I'm told its a common problem on E30's and can cause similar probs to how you describe.
Is there just the one plug under the inlet? Is it a fairly obvious electrical conection? Any more info would be great :)
massive
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Fri Sep 08, 2006 9:45 am

Its a round electrical connector (5 wires) under the inlet manifold (twist type). Easy to find.

If its corroded and green etc, this could be the problem as it is the power and ground feed to the injectors.
ropeman
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Fri Sep 08, 2006 9:49 am

Nice one, I'll check it out when I get home :)
ropeman
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Wed Sep 13, 2006 9:52 am

The plug checked out to be ok, but I do have some update on the symptoms:

If I get in the car (engine cold) and turn the ignition on, and leave it for 15 - 20 seconds then try and start it, it starts perfectly.

Any ideas?
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Brianmoooore
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Wed Sep 13, 2006 10:41 am

Anything temperature related - blue temp sensor.
ropeman
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Wed Sep 13, 2006 12:20 pm

Where is the blue temp sensor? I was thinking along the lines of the fuel system not pressureising as quick as it should.
massive
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Wed Sep 13, 2006 12:48 pm

It in the thermo housing next to a brown one - someone will post a diagram no doubt, saw on recently on another post
ropeman
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Wed Sep 13, 2006 12:53 pm

Thanks, will check it out.

My bro has just borrowed my car and says it could be a lazy 'lift pump'? Does that make any sence? Belive it or not I am quite mechanicly minded, but only when it comes to A series engines :)
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Brianmoooore
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Wed Sep 13, 2006 1:12 pm

It'll be early '88 0r older to have this "lift pump". They do fail, but the usual symptom is a very noisy main pump, and running out of puff at high revs/load. Possibly worth checking out though.
If you have this set up, both pumps can be replaced by a single in tank later one.
ropeman
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Wed Sep 13, 2006 2:37 pm

Ah, well that's done away with the lift pump :) one less thing to check.
325zimmer
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Wed Sep 13, 2006 3:46 pm

Mine does the same, I have changed everything you can think of from sensors through to engine loom and some and it still does it.
Its driving me crazy :cry:
The last thing i'm gonna change is the loom behind the dash.

If anyone else has any ideas please let me know!!

Cheers Pav
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Jonny_71
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Wed Sep 13, 2006 4:22 pm

Finally solved my starting probs last night, starting was gradually getting worse and worse upto the point where it just gave up last week. Checked all the usual suspects, pump, relays etc. Turns out the live feed to the coil was very weak, the thick green wire from pin 7 of the loom plug which ends up at the coil had very high resistance in it. Turns out that when the car had an immobiliser fitted about 10 years ago they spliced into the green wire but just did a 'twist the wires together and tape it up' job, rather than soldering the join, causing the excessive resistance in the wire, hence not enough power at the coil. Replaced a bit or wire and tidied it up and it now starts perfectly. So, maybe check the thick green wire? As a test I ran a piece of wire direct from the battery + to the coil + and it started first go.
325zimmer
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Wed Sep 13, 2006 4:45 pm

Oooh interesting....i know mine has had a couple alarms in the passed which have been ripped out and changed. I shall test and try that out.

I will let you know.

Cheers

Pav :D
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ropeman
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Wed Sep 13, 2006 4:51 pm

Hmmm and mine has electronic locking on a fob, I assumed this would have been standard, but I'll check the green wire. Did it happen all the time with you? My 325 only does it when it's cold or after about an hour from when it was last driven.
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Jonny_71
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Wed Sep 13, 2006 4:54 pm

The starting was definitely worse when cold, but to be honest it would happen when hot too sometimes. Hope you have some luck with it.
325zimmer
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Wed Sep 13, 2006 5:02 pm

When its really cold it sometimes starts straight away. The rest of the time it doesnt like starting.
But if you drive it then stop. the go to start it within 5 minutes it will start perfectly.
Anymore than 30 mins and doesnt like to start.
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ropeman
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Wed Sep 13, 2006 5:05 pm

325zimmer wrote:When its really cold it sometimes starts straight away. The rest of the time it doesnt like starting.
But if you drive it then stop. the go to start it within 5 minutes it will start perfectly.
Anymore than 30 mins and doesnt like to start.
Sounds just the same as mine, although I don't know about the really cold. I haven't had the car that long, but I reckon it will struggle as it gets colder.

Have you tried turning the ignition on for about 20 seconds before you try and start it? This seems to work on mine. Not a soloution, but I just wondered if we have almost identical problems?
massive
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Wed Sep 13, 2006 6:07 pm

ropeman wrote:
325zimmer wrote:When its really cold it sometimes starts straight away. The rest of the time it doesnt like starting.
But if you drive it then stop. the go to start it within 5 minutes it will start perfectly.
Anymore than 30 mins and doesnt like to start.

Have you tried turning the ignition on for about 20 seconds before you try and start it? This seems to work on mine. Not a soloution, but I just wondered if we have almost identical problems?
Are you sure someone hasn't dropped a diesel engine in it :D
ropeman
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Wed Sep 13, 2006 9:34 pm

massive wrote:
ropeman wrote:
325zimmer wrote:When its really cold it sometimes starts straight away. The rest of the time it doesnt like starting.
But if you drive it then stop. the go to start it within 5 minutes it will start perfectly.
Anymore than 30 mins and doesnt like to start.

Have you tried turning the ignition on for about 20 seconds before you try and start it? This seems to work on mine. Not a soloution, but I just wondered if we have almost identical problems?
Are you sure someone hasn't dropped a diesel engine in it :D

lol! actually my theory on leaving it for 20 seconds is rubish, tried it a fewtimes tonight.
325zimmer
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Mon Sep 18, 2006 8:26 am

Ok, at the weekend I tried running a new (+) to the coil, NO difference!!! :cry:
Its looks like someone had tried it before, as there was reminance of somesort of wiring left over near the ignition switch.

Now I haven't got a clue what to try next!! Except to change the wiring behind the dash :cry:

Anyone else got any more suggestions?

Pav
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bultjeboo
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Wed Sep 20, 2006 11:06 am

this is quite interesting i'm having all the same prob's with my 316 i'll give your most of your suggestions a go and see what happens.
cheers hayley :mad:
Im carless, BUT, hope to remedy that fairly soon, plus, need to actually be able to drive first so that gets priority!!
oze30
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Wed Sep 20, 2006 1:13 pm

mine does the same.. though I just get in the car, turn the key to posi 2, buckle up then start, aand it starts pretty much on beat. If i do a cold start, it turns and cooughs and sometimes catches.. others it splutters out. i think it could be a blocked fuel filter.. Will have to check that one later tonoght
325zimmer
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Tue Sep 26, 2006 3:40 pm

I've changed the filter and fuel lines, not that on mine.

I thought it might be my OBC, so I by-passed the the OBC relay, by bridging the green wires from the ignition to the relay. That didn't work either. :cry:

Looking at the wiring diagrams on: www.autolib.diakom.ru/ site. There seems is a difference in the looms between a 88 and a 90/91. On the 88, the green wire from the ignition switch splits off to various places one of which is the 'Overvoltage pretection relay (pin#86)', but on later model it does not.

Does anyone know where this 'Overvoltage pretection relay (pin#86)' is actually on the car?

Could this be an early design fault, then later rectified on later looms?

Sorry for the rant, It just frustrates me that i can't fix it! I think I've tried everything else!!!

I'd be much appreciated if anyone can help.

Cheers

Pav
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SGP
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Tue Sep 26, 2006 7:59 pm

Sometimes when I switch on the ignition the idle stabilizer valve takes a few seconds to come on (you can hear it buzzing) wonder why that is?Also I had a car in recently that a guy was having trouble starting and it turned out to be a cracked rotor arm,the arm and the distributor cap were changed and it's "never started as well as it does now",I think these two parts are often neglected coz they are fairly expensive to buy.
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Fix it till it is :)
325zimmer
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Wed Sep 27, 2006 10:01 am

I not noticed a delay on the idle valve.
but i have replaced the cap and arm, along with a whole list of other parts.
:(
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ropeman
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Wed Sep 27, 2006 10:17 am

Mine is still doing it too, next on the list is the cold start injector. Just need to find out what one looks like before I can replace it :) Anyone got a pic?
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