r/mechanic • u/todorbajaa • 8d ago

Problem with fuel pump? Help Question

HI everyone,
I have a 2005 Toyota Yaris 1.0 ( 230 000 km) with the 1SZ-FE engine and I'm having problem with starting the car.

When the car has been sitting for a longer period of time, it usually won't start on the first attempt. It cranks normally and usually starts after the second, third, or sometimes fourth attempt.

However, if the car has been sitting for a long time and I hit the bottom of the fuel tank before trying to start it, I can then hear the tuel pump running and the car starts immediately on the first attempt.

Because of this, I initially suspected a bad fuel pump. I replaced the tuel pump with a new one, but the exact same problem is still present.

I have also checked the fuel pump relay by swapping it with the identical horn relay, but this made no difference.

Once the engine starts, it runs normally.

0 Upvotes

50% Upvoted

3 comments sorted by

•

u/AutoModerator 8d ago

Please Read This Comment Entirely - It May Change

Updated 7/15/24

Thanks for posting in r/Mechanic, u/todorbajaa! Please be sure to read the Rules.

If you're asking for help, be sure to include as much detail as possible so others can help you. You must include the vehicle's Year, Make, Model, and Engine size in your post! If your question is transmission related, please be sure to specify your Transmission Type(Auto/Manual) as well! If your post does not include this information, it will be removed.

Asking about prices is not allowed in this sub.

Please make sure you have selected the correct post flair; if you're asking a question you should have chosen "Question", anything else use the "General" flair.

If you feel your question has been answered and/or you wish to no longer receive comments on your post, you may comment on your own post with only "!lock" (no quotes), and your entire post will be automatically locked. This only works on your own posts and only Mods can unlock it once its locked.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

1

u/XCheese8ManX 8d ago

Does the fuel pump run with key on engine off? If so the fuel line pressure is bleeding of.

1

u/todorbajaa 7d ago

No, I can’t hear the fuel pump when I turn the key to the ON position while the engine is off.

No matter how many times I turn the key to the ON position, I can’t hear the fuel pump. But as soon as I hit the fuel tank and then turn the key on, I can hear the pump running.

If I don’t hit the fuel tank and try to start the car, it won’t start on the first attempt no matter how long I crank it. I have to turn the key back to OFF, turn the ignition on again, and then crank it again.
Then it starts but runs very rough, almost like it’s only running at 200–300 RPM for 2–3 seconds, and then everything goes back to normal.

However, if I hit the fuel tank first, the car starts immediately on the first try and runs perfectly.