Saturday I changed the fuel pump and since then It has been acting up. When I start the car it dies right away. Sometimes if I rev it up it will stay running but sometimes when I do that it died. Then white and or black smoke comes from the exaust.
Why did you change the fuel pump?
1 Like
What pump did you install? A factory replacement style? Or performance aftermarket?
it was a one that I got from Walmart. I went out today and it will start but it dies and wont stay running.
The old one was bad.
Now you get to pull out that walmart part and do the job all over again. This time, get your fuel pump at a Nissan dealer.
1 Like
What is fuel pressure with key on? And running?
1 Like
If you believe the original problem was a defective fuel pump, and you installed a cheap, generic fuel pump, and the problem continues then one of two things is true. Either the new fuel pump is a piece of junk, and no better than the one you replaced, or the problem was something else all along.
Personally, I would never cheap out on a fuel pump, because the cost savings isn’t worth it. Say, for the sake of argument, that a good brand such as Denso First Time Fit, Bosch, or Delphi costs $150, and a cheap “Ebay special” brand costs $60 with free shipping.
If that cheap fuel pump should fail, just the cost of having the car towed home will exceed any potential savings. Then, of course, there’s the cost of a new fuel pump, and the time and effort to do the job again. And, of course, if the car breaks down far from home, now you’re paying a shop $800 or more to do a fuel pump which you could have done yourself at home for about $150.
That being said, many fuel pumps are incorrectly diagnosed as bad, when the actual problem is a defective (external) fuel filter, fuel pressure regulator, or defective fuel injector(s). It is entirely possible that the problem has not been resolved by replacing the fuel pump, because the fuel pump was not defective to begin with.
If you have access to a fuel pressure gauge, you can measure the fuel pressure with the engine running, with the engine off, and view the decay over time when the engine is turned off. If you have access to a scan tool which shows live data, you can view the short-term and long-term fuel trims to see if the PCM is trying to compensate for a weak fuel pump/clogged fuel filter, defective fuel injector(s), etc.
3 Likes
Walmart sells fuel pumps? That’s what I’m trying to wrap my head around.
6 Likes
I suspect the Walmart fuel pump was actually a third party retailer from the Walmart website.
4 Likes
Ah, that would make sense.
I didn’t recall ever seeing anything resembling an automobile fuel pump at my local store. Maybe, just maybe, a fuel pump for a small engine…but if you 're trying to “rig” a lawnmower fuel pump to work on your car, well brother, you may have bigger problems…
It’s possible the replacement pump is defective. More likely though is a problem with the install job. Perhaps there was debris inside the pump that is now clogging the fuel injectors. Or the debris got into the lines just by installing the pump. I had a VW Rabbit quite some years ago and nearly every time I disconnected a fuel line (to say install a new fuel filter) debris would somehow get into the line and clog the fuel injection system. The CIS injection system on that model was very sensitive to any grit at all in the fuel. The upside for the CIS, cleaning its guts didn’t take much time.
Or perhaps you forgot to connect a vacuum hose or an electrical connection. Double check all those. Especially all the PCV-associated hoses. Does your car use a separate fuel pressure regulator installed on the fuel rail? If so, check to make sure everything is connected and there’s no fuel inside the vacuum connection to that device.
Still can’t seeing anything wrong? It sounds like it is running way too rich. Possibilities include
- Fuel pressure too high
- Injectors stuck open
- Computer isn’t pulsing injectors correctly.
- Computer thinks coolant or ambient temperature is winter-time cold, like -40 deg F, when it is actually summer and warm or hot.
So measure fuel pressure, do an injector volume flow test, verify coolant temp and ambient temps sensors are working.
Here’s an afterthought. It’s possible when working on fuel injection systems to get a lot of gasoline in the cylinders. You say you can get it to start ok, but have you tried then letting it idle for 15-20 minutes? That would clear any gasoline from the install and testing out of the cylinders. Usually when this happens however it won’t start at all until all the spark plugs are removed and the cylinders have a couple days to air out.
A several days old thread, buy maybe the fuel pressure regulator has given completely up; or had given up before the pump replacement.
Raw gas pouring into the cylinders could cause those kind of symptoms.