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Fuel pump replacement after-effects

My old 0BW is starting to get expensive in its old age. In the last three weeks it's had three separate major part replacements. First week, I had a $1300 dinger for a new throttle body and sensor. Second week, my battery conked out, but fortunately I went aftermarket for the replacement and got it done for around $100. And now this week, all of a sudden the fuel pump conks out, and now I got dinged for $800! Yeesh!

Anyways, I'm venting, nevermind. There is one effect that I'm seeing after the fuel pump replacement. I'm finding that the car no longer starts reliably. Later in the same day I got it fixed, I found out twice where it no longer was getting fuel again. What would typically happen is that I'll start it up, it'll work for a few seconds and then just die. Then I'd try to restart it several times (maybe 5, 6, or 10 times) and it will not ignite, and then randomly it will all of sudden work again. Thank god for the brand new battery, it's trooping along activating the starter for as many times I'm retrying. Now is this to be expected from a new fuel pump? I mean will there be some air or moisture in the lines after the pump replacement, and it just needs to work its way out of the system? Also I noticed these problems occurred during a major rain downpour, so I'm wondering if that was a coincidence or not. It's been acting okay today, but its hot and sunny today. I got the pump replaced on Friday, and the dealer's service centre is unfortunately closed on the weekend, so I can't talk to them till Monday.

Yousuf Khan

Reply to
Yousuf Khan
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The pump supplies more fuel then the engine can use and the excess is returned to the tank so there is no possibility there can be air in the system. What about the fuel filter? Was it replaced along with the new pump? Thinking the new fuel pump replacement and your current problem have nothing in common. Remember the engine also needs spark to run. You need to determine if the no-run problem is because of no fuel or no spark. Also the fuel pump has a relay in the circuit. There is a chance the pump that was replaced was still good and the original problem was a bad fuel pomp relay.

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Reply to
johninKY

I second the fuel pump relay theory.

By the way, why did your change the throttle body? and the sensor?

Good luck!

john> The pump supplies more fuel then the engine can use and the excess is

Reply to
AS

Oh well, that's a long story, you can read about it here:

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Yousuf Khan

Reply to
YKhan

I would assume that the fuel filter was replaced. I didn't really ask too many questions at the dealership this time around, I was just glad to have the car back. I'll ask about the fuel pump relay too. I will be going to the dealership as soon as it opens tomorrow, so I'll get a chance to ask these questions.

I've not seen this dealership screw up with their work too much before. But there's always a first time. Thanks.

Yousuf Khan

Reply to
YKhan

Hi,

I've seen a few throttle bodies get pretty "goo'd up" if they weren't given a shot of spray cleaner every so often. Wonder if that's what happened to his, and continued use led to excessive wear? Just reaching here...

Rick

Reply to
Rick Courtright

Dunno if his car is so equipped, but, I've also heard of the IACV being damaged by the use of the improper solvent to clean the TB.

????

Carl

Reply to
Carl 1 Lucky Texan

It was already too late, and if I had gone to another dealer for a second opinion, I would've been dinged for more diagnostic fees.

Anyways, back to the current problem. According to them, the new fuel pump they installed was defective. They said that when they measured the fuel pressure, they expected to see 50 psi. They said they were seeing 38 psi at most, and sometimes they were seeing *zero* psi. So they replaced the unit again, and this time they gave me a loaner car (basic '08 Impreza), and have decided to evaluate it for several days to make sure it's truly working. They've now had it for 3 days since putting the second fuel pump in.

However, while they were testing the fuel pump they said they discovered that the front O2 sensor was not working properly, so I'm getting ready for yet another dinging to my credit card.

Yousuf Khan

Reply to
YKhan

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