Car is hard to start.

[Hayden]

Gday mates. I have a 1990 Holden Vn commodore, It is hard to start even when its warm. I will turn the key and it will crank for a good 8 seconds then ill stop, ill try again it will keep cranking for another 8 or so seconds, ill stop again then it will start after cranking for about 3-4 seconds. Once it starts it will run shit until you give it a few revs. After that it runs fine. If you turn the car off after it has a run and then go to start it again it starts fine but if you try doing that after 10 or so minutes it will find it hard to start. Anyone know what the problem could be? Cheers.

Topic

[college man]

What we need to determine is are we loosing spark or fuel.
more in this link.

http://www.ericthecarguy.com/faq/solving-automotive-no-start-problems

[EricTheCarGuy]

Given the age of the vehicle I might be looking to the coolant temp sensor. If it sends faulty readings to the computer then the fuel mix will be off which can cause hard starting. Listed in the service manual they give resistance values for given temperatures. All you need do is know the temp you’re testing at and have an ohm meter to check the resistance. The article College man posted will also provide useful info.

Keep us posted on your progress.

[Matt]

don’t know if your vehicle is set up like mine, but I just changed my fuel pump because it had the same symptoms as yours. There is a check valve in my fuel pump that maintains fuel pressure after the vehicle is off. If that check valve leaks, you loose the fuel pressure and then the pressure has to be built back up on start causing a hard start.

[Hayden]

[quote=”EricTheCarGuy” post=111256]Given the age of the vehicle I might be looking to the coolant temp sensor. If it sends faulty readings to the computer then the fuel mix will be off which can cause hard starting. Listed in the service manual they give resistance values for given temperatures. All you need do is know the temp you’re testing at and have an ohm meter to check the resistance. The article College man posted will also provide useful info.

Keep us posted on your progress.[/quote]
thank you so much. It was the coolant temp sensor. Replaced it and it starts first crank everytime. I have also noticed ive been getting more fuel mileage.

[Author]

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