Can a fuel pump that is supposedly starting to give troubles but does not casue the check engine light to come on (and the car seems to run fine) send a code to signal its faulty?
They never told me the code at the dealership. My check engine light just came on the other day and the car managed to die once while ideling but now the car runs fine and no check engine light, so I took it to the dealership just to get checked out and now they say codes came up showing it needs an egr sensor, egr valve and a fuel pump. I just can't see the car needing all that when it seems to run fine again and the check engine light has not returned. I think they are just searching for something because when I questioned about the pump they said they thought I could get away without replacing it. Just thought I would check to see if a failing pump would even through a code, I didn't think it would, especailly when there is no check engine light.
The electrical side of a pump is where the codes come up (primary or secondary electric codes), but generally not pump flow, since the computer doesnt monitor it, per se. Like I said before, a lean code can indicate a weak pump, but other things can cause that code also. The thing with codes is that they give us an area to search, but dont absolutely tell us what component is at fault.
WIth the EGR, I might clean it and use a meter to see if the EVR is calibrated. Then see what codes pop up in the future. FWIW, if the EGR fails (doesnt open at part throttle), it can cause a leanness at part throttle, which could pop a lean code. And if the EGR opened at idle, it could cause a rough idle or stalling. Again, the deductive process at work. Diagnostics are needed to know better.
And you can pull your own codes with a paperclip if you desire (I like to actually see the codes myself). As enthusiasts, we might try and clean a component, rather than replace it. I understand the dealer (or a shop's) perspective - they dont want a come-back, so they tend to be a little broad in their diagnoses sometimes. I would do the same if I had a shop.