Cold hard start warm no start

Kerpre · Post by **Kerpre** » 26 May 2019, 18:32

Hi guys so my infamous 2000 C70 is finally running after it’s head replacement.

I am getting an intermittent nonstart or hard start when cold and she just will not start again of it has been running( if I go to fill her up etc).

If it starts when cold I have to feather the throttle for a second or 2 and then she idles fine.

However when she has been running for a while and I got to restart it just won’t, I try starter fluid and it will stumble to life and then die within a second.

Once running it drives fine, fuel economy seems a bit higher 23L/100km.

Any suggestions on what to look for?

I can confirm crank sensor and cam sensors are good.
I have spark
Fuel pressure is 55psi at rail and the injectors are pulsing
Battery is good
No vacuum leaks that I have been able to find

Please help I love driving this car!

Post by **wizechatmgr** » 26 May 2019, 20:47

Temp sensor by thermostat going bad? VAC leak?

Kerpre · Post by **Kerpre** » 26 May 2019, 20:57

My thought exactly, have a new temp sensor on its way, attacking the cheaper stuff first. Thanks you

Post by **wizechatmgr** » 26 May 2019, 22:53

Kerpre wrote: 26 May 2019, 20:57 My thought exactly, have a new temp sensor on its way, attacking the cheaper stuff first. Thanks you

That can actually be tested with a multimeter so you don't just start throwing money at the car randomly...

That said, if it is over 10 years old then I'd just replace it.

Post by **RickHaleParker** » 26 May 2019, 23:09

wizechatmgr wrote: 26 May 2019, 22:53 That can actually be tested with a multimeter so you don't just start throwing money at the car randomly...

: ECTS.PNG (7.93 KiB) Viewed 1690 times

R ~ 5321.65903 + (-144.171747 T) + (0.95432339 T²)

Example T = 10°C:
R ~ 5321.65903 + (-144.171747 10) + (0.95432339 10²)
R ~ 5321.65903 + (-1441.71747) + (0.95432339 * 100)
R ~ 5321.65903 + (-1441.71747) + (95.432339)
R ~ 3975.373899

~ 7.5% error from the chart.

Kerpre · Post by **Kerpre** » 26 May 2019, 23:14

Your a Gem Rick, thanks heaps mate, I’ll go have a look now

Kerpre · Post by **Kerpre** » 26 May 2019, 23:25

Ok so I got 3k ohms at 16 Celsius
Car started so letting it idle to operating temp and will test again

Kerpre · Post by **Kerpre** » 26 May 2019, 23:34

While i can get it to start, this could be a completely different problem or help solve the current. Video is at idle in park, idles perfect. When I put it into gear it stumbles and carries on, not severe but enough to take notice

Kerpre · Post by **Kerpre** » 26 May 2019, 23:41

At operating temperature (needle won’t go any higher)
I get 0.5k ohm
I also get 0.5v on one pin and 5v on he other

Kerpre · Post by **Kerpre** » 26 May 2019, 23:49

Ok sorry for bombarding the page, I only get a small amount of time to work on car each day.
I turned car off, then straight back on, no issues, again, and again it was fine, without removing key

I removed the key, locked it, open and tried to start, no go. Maybe this i fo is of use to anyone in the know?