Hard starting?

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bluejay
Joined: Fri 16 Jan, 2004 13:40
Posts: 182

  Z1 roadster

Hard starting?

Post by bluejay » Thu 31 Jan, 2019 16:47

So over the last year on and off the Z1 decides it doesn't like turning on. Difficult starting with wild statioanry initially, but when it runs it is OK.

This first started when the v-power was changed, added cleaning stuff to the fuel with normal unleaded and it was fine again, but now it started doing it with regular fuel too (unleaded 95).

Discussed this at length and we think it could be due to ethanol content in the fuel, but also possible deteriation of the fuel lines, I read somewhere? Butyl lines don't do very well with ethanol fuels?

So anyone else has observed this?

Robert

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Gazza
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  M roadster S54
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Re: Hard starting?

Post by Gazza » Thu 31 Jan, 2019 20:21

Mine turns over fine but like it isn’t getting enough fuel and put put puting into life from cold.
Gazza

"Understeer is when you hit the wall with the front of the car, oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall and torque is how far you take the wall with you"

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blue_and_white
Joined: Sat 29 Jul, 2017 00:19
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Re: Hard starting?

Post by blue_and_white » Fri 01 Feb, 2019 07:05

There was a cold start mod for the M20 engine back in the day which basically consisted of a small loom, a relay and a resistor . As I remember, the switching side of the relay connected to the starter motor so when cranking, it would activate the relay. This then was connected to the engine temp switch and when activated, switched in the additional resistor to alter the total resistance of the coolant temp switch hence tricking the ecu into thinking it’s is colder than it actually is therefore a richer cold start. You got a choice of three resistors which I think were around 1000 ohms but I’m really not sure, it was 25 years ago . Wether anyone still makes this mod or could rig one up I’m not sure. Good luck


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bluejay
Joined: Fri 16 Jan, 2004 13:40
Posts: 182

  Z1 roadster

Re: Hard starting?

Post by bluejay » Mon 02 Sep, 2019 06:49

After the whole summer starting OK, it is back again... going to try engine cleaner again through the petrol see if that makes a difference...

It costs a lot of extra fuel this, easily takes 20-30miles of my range of a full tank...

Any other suggestions?

felix
Joined: Sat 02 Jul, 2005 17:25
Posts: 562

  Z1 roadster

Re: Hard starting?

Post by felix » Mon 02 Sep, 2019 13:32

Check the fuel pressure?

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bluejay
Joined: Fri 16 Jan, 2004 13:40
Posts: 182

  Z1 roadster

Re: Hard starting?

Post by bluejay » Mon 02 Sep, 2019 14:10

Fuel pressure is fine, it started well over the whole summer.... :head:

felix
Joined: Sat 02 Jul, 2005 17:25
Posts: 562

  Z1 roadster

Re: Hard starting?

Post by felix » Mon 02 Sep, 2019 14:22

Have you actually checked it or do you just believe it to be OK because the car started fine over the summer?

For an engine to start and run it needs fuel, spark and compression. When fault finding it's best to make a minimum number of assumptions but just to start checking things methodically.

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bluejay
Joined: Fri 16 Jan, 2004 13:40
Posts: 182

  Z1 roadster

Re: Hard starting?

Post by bluejay » Tue 03 Sep, 2019 06:30

I had similar problems last year, also after the summer, seems outside temperature related....

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Gazza
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  M roadster S54
Location: Romford Essex

Re: Hard starting?

Post by Gazza » Thu 05 Sep, 2019 21:03

Could be an air leak
Gazza

"Understeer is when you hit the wall with the front of the car, oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall and torque is how far you take the wall with you"

Z3 S54 M roadster Image, BMW Z1, BMW M3 CSL, Z4M Coupe
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