Mazda Tribute losing power

Maintenance/Repairs
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1

Hi guys I have an 08 mazda tribute 2.3litre 5 speed. The truck started losing power and bucking really bad about 2 months ago. If I shut the truck off and let it sit for a few minutes, then start it back up, it runs fine for maybe 10 minutes or maybe a week then it eventually starts missing and bucking again. It throws the code p0191 which is the fuel rail pressure sensor. I have replaced the sensor twice and put new plugs, wires, coil packs, fuel filter and even replaced the pcm. The truck is still doing the same thing and throwing the same code. My Mechanic and myself are stumped. Does anyone have any ideas?

Any help would be really appreciated as I have already sunk more than $1500 into this truck with nothing getting

2

Have you measured the fuel pressure? This sounds like the fuel pump or its relay starting to go.

3

Oops, I just realized where this was posted. This should be a separate topic. Shout-out to @lackeyjr

1 Like
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5

Yes I had the fuel pressure tested and it had 36lbs at the rail.

6

[quote=“Coryb1971, post:5, topic:94133, full:true”]
Yes I had the fuel pressure tested and it had 36lbs at the rail.
[/quote]I think you have found the problem. I believe it should be something like 55 - 70 psi.

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[quote=“NYBo, post:6, topic:94133, full:true”]

[quote=“Coryb1971, post:5, topic:94133, full:true”]
Yes I had the fuel pressure tested and it had 36lbs at the rail.
[/quote]I think you have found the problem. I believe it should be something like 55 - 70 psi.
[/quote]That being said, you need to find out why fuel pressure is too low before throwing parts at it.

8

Assuming the fuel pressure is indeed far below specs, I would also expect to see P0171, as low fuel pressure IS a lean condition

9

It did throw that code P0171. Is the fuel pressure supposed to be 55-70 at idle or when reving the engine.