starting problems again

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alfa12177
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Post Sun Mar 02, 2014 6:40 am

morning .car has been getting harder to start over the last couple of weeks and running rough until up to temp.now it wont start at all.plenty of fuel in it new fuel filter fitted fuelpump defo working.where should I start looking next ? car does turn over many thanks chris great forum by the way
Last edited by alfa12177 on Sun Mar 02, 2014 8:23 am, edited 1 time in total.
Grrrmachine
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Post Sun Mar 02, 2014 8:03 am

We need to know what car it is to give proper answers. Engine model and year please.
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alfa12177
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Post Sun Mar 02, 2014 8:13 am

hi .1988 320i
jmc330i
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Post Sun Mar 02, 2014 8:42 am

I'd be popping the spark plugs out and looking to see if they're sooted up. Give them a good clean with a wire brush, check for a spark on each plug (rest each plug in turn on the rocker cover so the metal screw thread is grounding out on the rocker and turn the engine over - a spark should be visible) and if each plug sparks ok after you've cleaned then, pop them back in and see if the engine will fire up.

If it does, I'd be checking the blue temp sensor, which if faulty (or the plug between sensor and ECU) will cause the engine to run rich and soot the plugs up. If left to carry on, (especially if you've been cranking the engine lots to try and start it) the plugs can get so dirty that they won't spark cleanly and eventually not well enough to fire the engine.

Blue temp sensor testing - http://www.e30zone.net/e30zonewiki/inde ... or#Testing

Checking for spark - http://www.e30zone.net/e30zonewiki/inde ... _for_Spark
James
'91 325i Sport
'93 318i touring 16v
Grrrmachine
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Post Sun Mar 02, 2014 10:32 am

As JMC says, check your sparks. If you're driving the car with lots of little stops rather than a good long drive, then it'll constantly be in "warm up" mode and run rich, fouling the plugs. A simple service (new plugs, oil and filters) should set things straight.

If your plugs are ok, I'd start looking around all the rubber air intake hoses for cracks or splits. Even a small hole can stop a cold engine from starting.
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alfa12177
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Post Sun Mar 02, 2014 11:29 am

thanks for the help will let you know how i get on
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alfa12177
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Post Mon Mar 03, 2014 6:22 pm

new plugs fitted car starts. still a bit lumpy until up to temp.
Grrrmachine
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Post Mon Mar 03, 2014 6:56 pm

We still need to know what the old plugs looked like.
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alfa12177
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Post Mon Mar 03, 2014 7:17 pm

very very black
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Brianmoooore
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Post Mon Mar 03, 2014 7:22 pm

Time to measure the blue temp. sensor resistance AT THE ECU PLUG.
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alfa12177
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Post Mon Mar 03, 2014 7:27 pm

how do you do that ?
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BenHar
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Post Mon Mar 03, 2014 7:29 pm

jmc330i
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Post Mon Mar 03, 2014 9:30 pm

Brianmoooore wrote:Time to measure the blue temp. sensor resistance AT THE ECU PLUG.
alfa12177 wrote:how do you do that ?
I posted the link you need in my first post :wink:
James
'91 325i Sport
'93 318i touring 16v