Installed new fuel pump, but car still feels "off"...any thoughts?

Maintenance/Repairs
1

Hi, I had a new fuel pump installed on my 1997 Honda Civic (145K miles) last week after it started hesitating and bucking one day and then the Check Engine light came on. I picked the car up last Thursday, and it runs and starts, but I still feel “something off”…it seems to have small surges of power/lack of power while I drive. Again, always starts and runs but it just doesn’t feel right. I am not super car savvy and would like to return to the mechanic tomorrow with a little bit more knowledge about what may be going on. I spent quite a lot of money on the repair and wonder if they know what they’re doing; any advice would be greatly appreciated. Thank you

2

It could be many things but here’s a start:

That vintage honda has been known to have issues with the main relay. It basically provides power to the fuel pump and the part has a tendency to have intermittent problems.
It often affects starting but can also affect driving. Here’s a link on the part.
http://www.tegger.com/hondafaq/startproblems.html#mainrelay
The part can often actually be fixed inexpensively by resoldering connections.

Has your mechanic checked the fuel pressure? That could also be a cause for what you are describing.
No doubt he’s changed the fuel filter. A clogged filter could definitely do what you describe.

3

The fuel pump provides a constant fuel pressure to the fuel injectors. It’s the job of the fuel pressure regulator to control the fuel pressure to the fuel injectors. Have them check for a leaking/malfunctioning fuel pressure regulator.

Tester

4

thank you-so the fuel pressure regulator is a different matter than the actual fuel pump? wouldn’t they have made sure “everything” was working in sync? Or did putting in a new fuel pump just address part of the issue?

5

Usually when one replaces a fuel pump, you check to make sure the pressure is correct because those things vary in pressure. That’s inherent of the part but there’s a fuel pressure regulator in the FI system that makes sure that the injectors get the right pressure - that’s the part he may may need to look at.

6

Yep! The fuel pump is mounted in the gas tank. The fuel pressure regulator is mounted on the fuel rail on the engine.

Tester

7

thank you for your advice-much appreciated