Hard to start in mornings-plugs replace

MANNY71

MEMBER
2005 SUZUKI FORENZA
4 CYL
2WD
MANUAL
27,000 MILES

Car has low mileage-27,000, water pump & timing belt replaced in 2007. Plugs replaced-one had a rusty plug. Not overheating. Once its started in the morning-takes a while- it runs all day with no problem starting again. Its only the mornings it doesnt like to start. You can hear the fuel pump come on when you turn the key to start. What can be the problem or what can I check to see what the problem could be?

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

Hard to start can be due to a number of different reasons. It could be weak fuel pump, dirty throttle bore, worn out spark plugs, low cylinder compression, faulty mass air flow sensor.
It is possible to have hard start when it is cold due to a failing fuel pressure regulator. And as it warms up the regulator functions properly and you don't have any starting issue.

Thake a look at this helpful guide:

https://www.2carpros.com/articles/engine-cranks-excessively-before-starting

A good first step would be to check the fuel pressure when the engine cold. This can help determine the issue. With the key on and engine off it should have 55-57 PSI of fuel pressure.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

It will also be a good idea to check and clean the intake components like the throttle body and the mass air flow sensor.

https://www.2carpros.com/articles/throttle-actuator-service
https://www.2carpros.com/articles/mass-air-flow-service

Please let me know of any questions.
Thank you.

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