325 sport crap from cold start

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lukec88
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Mon Aug 06, 2012 11:22 pm

my 89 sport is pretty crap from first start up. it is very crap in the lower revs and splutters a lot but runs fine once warmed up. any ideas if the cold start relay (if i have one) would be the cause of this or is it likely to be the coolant temp sensor? any ideas and help is appreciated
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Diamond Schwartz black 1989 325I Sport MTech 2.
Rtaylor2208
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Mon Aug 06, 2012 11:29 pm

It could be a number of things, the usual suspects are the blue temp sensor, air leaks, old or faulty plugs, dizzy, rotor, TPS, ICV etc etc.

The idling guide in the wiki is the best bet to test each component logically. It will help you narrow down the problem without spending any money on unneccessary parts or labour.
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lukec88
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Mon Aug 06, 2012 11:33 pm

i am waiting for some plugs to be delivered i ordered them thursday. i have done around 8-10k miles in it since owning it and the service light was on before i got it. its had all filters changed etc and a couple of oil changes just havnt done the spark plugs until i get them. i will try that to start. then ill do a multimeter test on the blue temp sensor if the plugs dont help, then if i have the cold start relay ill change that and go through the list as i need to. :)
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Diamond Schwartz black 1989 325I Sport MTech 2.
Rtaylor2208
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Mon Aug 06, 2012 11:38 pm

Your car is the same age as mine on a G and there is no cold start valve on mine. The ECU works out the mixture based on input from the TPS, ICV, AFM and blue temp sensor from memory.

So a fault in any can and will contribute to a cold start issue.

I have been in the same position for mine and trust me spendning money is not neccessarily the way to go.
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lukec88
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Mon Aug 06, 2012 11:39 pm

thats fair enough but changing the plugs needs doing anyway so i dont mind spending on that part. if it doesnt help at all i will check those things and go from there.
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Diamond Schwartz black 1989 325I Sport MTech 2.
mcbonio
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Tue Aug 07, 2012 3:06 pm

I'd test the blue temp sensor first. I had similar cold start problems to you and a warm start issue too. Choked up on both a cold and a warm start, always smelled a bit rich - overfueling. I tested the blue temp sensor and it seemed fine, within acceptable range.?

After much head scratching I replaced it anyway and it solved both problems.! Very cheap too.
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lukec88
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Wed Aug 08, 2012 12:00 am

anyone know the part number for a 89 325 sport coolant temp sensor then?
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Diamond Schwartz black 1989 325I Sport MTech 2.
Meatballs82
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Wed Aug 08, 2012 9:42 am

lukec88 wrote:anyone know the part number for a 89 325 sport coolant temp sensor then?

13621709966

You coming to Jims on Sat? I can bring one along for ya
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Grrrmachine
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Wed Aug 08, 2012 9:52 am

Have you TESTED the temp sensor, before ordering a replacement?

Swapping it out for no reason has a chance of causing as many problems as it fixes. For more info:

http://www.e30zone.net/e30zonewiki/inde ... emp_Sensor
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lukec88
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Wed Aug 08, 2012 6:06 pm

No havnt tested it yet. But can it really do that much harm to change it and try it out? What's happening at jims sat?
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Diamond Schwartz black 1989 325I Sport MTech 2.
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RickyRed
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Wed Aug 08, 2012 9:26 pm

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