Cold start

discussions specific to the 907IE
Moses
Posts: 16
Joined: Fri May 06, 2016 2:28 am
model: 907 I.E.
year: 1991
Location: New Zealand

Cold start

Post by Moses »

Hi guys, I previously posted about my 907 smoking, that seems to have improved with the replacement of a split valve seal, but I'm having trouble with cold starting, it initially fires then dies, I have to give it 3/4 or more on the cold start control and crank it for a while to eventually fire up, then it runs rough, blows black smoke, seems to be over fuelling until it finally clears. It's recently had the settings etc set by a guy who knows his stuff but a bit perplexed as where to head to next. Any thoughts?
User avatar
Derek
paso grand pooh-bah
Posts: 768
Joined: Thu Nov 03, 2011 10:13 am
model: 907 I.E.
year: 1994
Location: Scotland

Re: Cold start

Post by Derek »

The cold start mixture is set by the ECU using the outputs it gets from the water temperature and air temperature sensors. It is possible the water temperature sensor is faulty.
However I'm more inclined to think that the throttle bodies and TPS are not set up correctly. The TPS setting in particular is crucial for an engine to start easily and run well. You can get the correct procedure from Brad Black's website : http://www.bikeboy.org/ducati2vthrottleb.html
1994 907ie
2017 Supersport 939
2015 Scrambler Classic
1982 Pantah 500SL (now sold)


Scotland
Moses
Posts: 16
Joined: Fri May 06, 2016 2:28 am
model: 907 I.E.
year: 1991
Location: New Zealand

Re: Cold start

Post by Moses »

Thanks for the info, I'll get to work on your suggestions. If the water temp sensor is faulty, would it be giving a false reading to the temp gauge, that seems to be working fine?

Cheers
Bluey
Posts: 90
Joined: Fri May 01, 2015 9:31 pm
model: 907 I.E.
year: 1991
Location: Australia

Re: Cold start

Post by Bluey »

Moses wrote:Thanks for the info, I'll get to work on your suggestions. If the water temp sensor is faulty, would it be giving a false reading to the temp gauge, that seems to be working fine?
I can't speak from the top of mind for all models but the ecu sensor is separate to the dash sensor...
User avatar
Derek
paso grand pooh-bah
Posts: 768
Joined: Thu Nov 03, 2011 10:13 am
model: 907 I.E.
year: 1994
Location: Scotland

Re: Cold start

Post by Derek »

Bluey wrote:
Moses wrote:Thanks for the info, I'll get to work on your suggestions. If the water temp sensor is faulty, would it be giving a false reading to the temp gauge, that seems to be working fine?
I can't speak from the top of mind for all models but the ecu sensor is separate to the dash sensor...
That's correct. The metal tube that connects the header tank and top hose to the other side of the cooling circuit has 3 sensors. From the right they are; the thermal switch for the radiator fan, temperature sensor for the ECU, temperature sender for the dash display. There is also an earth connection at the dash sender but if it is faulty it should only affect the display as the switch and sensor do not require an earth.
The temperature sensors are quite expensive from Ducati but they are the same as that fitted to many Fiats. The sensor (WS05 or WS09) for a Fiat Punto 8V 1.2L is the same and can be bought for around £15.
1994 907ie
2017 Supersport 939
2015 Scrambler Classic
1982 Pantah 500SL (now sold)


Scotland
Tamburinifan
paso grand pooh-bah
Posts: 1527
Joined: Thu Jun 21, 2007 12:00 am
model: 907 I.E.
year: 1991
Location: Gothenburg, SWEDEN

Re: Cold start

Post by Tamburinifan »

If a sensor is faulty, the ECU goes into Limp-home map.
It gives more fuel allover.
When driving, is it normal or signs of running fat, excessive exhaust smoke, if so, blue or black??
Gert

907 I.E. -91
M900 -97
MTS 1100s -07
Moses
Posts: 16
Joined: Fri May 06, 2016 2:28 am
model: 907 I.E.
year: 1991
Location: New Zealand

Re: Cold start

Post by Moses »

When starting from cold or even after being switched off for a short time, it will immediately fire up smoothly but will cut out out, then it needs throttle and cranking to get going again, it will then run rough and blow some black smoke indicative of over fuelling until it smooths out and runs smooth. During normal running it goes fine and doesn't blow smoke.
Tamburinifan
paso grand pooh-bah
Posts: 1527
Joined: Thu Jun 21, 2007 12:00 am
model: 907 I.E.
year: 1991
Location: Gothenburg, SWEDEN

Re: Cold start

Post by Tamburinifan »

The ECU has an enriched startcycle for 3000 RPM, like 2.5 minutes
at idle. Same cycle every start.
When on the road, stopping f a minute at idle, no black smoke
when revving?
It's recently had the settings etc set by a guy who knows his stuff but a bit perplexed as where to head to next. Any thoughts?
What exactly did he do?
Gert

907 I.E. -91
M900 -97
MTS 1100s -07
Moses
Posts: 16
Joined: Fri May 06, 2016 2:28 am
model: 907 I.E.
year: 1991
Location: New Zealand

Re: Cold start

Post by Moses »

He went right through the settings, trim, tips etc, was running well but this problem which was intermittent has become more consistent. Occasionally it starts fine with no problem, although it's been a while since it did that.
Only smoking at the initial start up. If I pull over while riding and switch off, it will start fine immediately but if I wait say 10-15 minutes, I'll most likely have problems when I start, although not every time.
Tamburinifan
paso grand pooh-bah
Posts: 1527
Joined: Thu Jun 21, 2007 12:00 am
model: 907 I.E.
year: 1991
Location: Gothenburg, SWEDEN

Re: Cold start

Post by Tamburinifan »

If valves and all injection settings are good, l'd check ignition.
Try a set of fresh plugs, then try another set of coils.
Did he set the CO as well?
A quick test if it's runnin a bit fat is to open both air screws on the
throttlebodies 1/5 of a turn and see what happends.
Make sure you can return them to previous position exactly.
Gert

907 I.E. -91
M900 -97
MTS 1100s -07
User avatar
Derek
paso grand pooh-bah
Posts: 768
Joined: Thu Nov 03, 2011 10:13 am
model: 907 I.E.
year: 1994
Location: Scotland

Re: Cold start

Post by Derek »

Tamburinifan wrote:If a sensor is faulty, the ECU goes into Limp-home map.
It gives more fuel allover.
Only if the output is out of range. Such as if it is short circuit or open circuit. It can be faulty but still putting out a signal that is within the normal range but at at extreme end of that range so that the bike runs very rich or very lean. Since it is an NTC sensor the higher it's resistance, due to an internal fault or (more commonly) corrosion on the connectors, the richer the mixture becomes.
1994 907ie
2017 Supersport 939
2015 Scrambler Classic
1982 Pantah 500SL (now sold)


Scotland
Moses
Posts: 16
Joined: Fri May 06, 2016 2:28 am
model: 907 I.E.
year: 1991
Location: New Zealand

Re: Cold start

Post by Moses »

Thanks for the input, the co was done, my gut feeling is the settings are fine but either a connection or a sensor is playing up, I'm currently going over all the connectors I can find and will look at temp sensor, possibly replace.
Moses
Posts: 16
Joined: Fri May 06, 2016 2:28 am
model: 907 I.E.
year: 1991
Location: New Zealand

Re: Cold start

Post by Moses »

Hi Derek, I can't get anywhere with the fiat people here in NZ as the numbers You quote don't register, do you have any other info, it seems they also need a chassis no to open up the system, doesn't make sense to me, I thought they could go into a parts file etc.
Tried Ducati but they no longer make it.

Cheers

Steve
Mc tool
paso grand pooh-bah
Posts: 1873
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Newzealand

Re: Cold start

Post by Mc tool »

Try ebay. I have found that Kiwi parts people are as helpful as hell if all they have to do is find a part # but ask them for an oil pressure sender 10x1mm tapered thread , 7lb's cracking , 6.3mm spade terminal, and they look at you like your mad. It can be #uckin frustrating knowing the dumb arses probly have the part but are just to stupid to know it. I sometimes use ebay as a source of info , often you can get the correct part no or description and what else it fits ,and the pix can help too as you can often read the writing on the part in the pic .

https://www.ebay.com/itm/Fiat-Punto-Coo ... Tn&vxp=mtr
This may be the right one :)
I wish I was young again............Id be heaps smarter than last time
Andrew2
paso grand pooh-bah
Posts: 574
Joined: Thu Oct 27, 2011 7:47 am
model: 750 Sport
year: 1988
Location: Wollongong,Australia

Re: Cold start

Post by Andrew2 »

Moses wrote: If I pull over while riding and switch off, it will start fine immediately but if I wait say 10-15 minutes, I'll most likely have problems when I start, although not every time.
As Derek said it sounds like a temp problem if it plays up after it has had a chance to cool for a bit.
Post Reply