Hi all,
‘02 Park Avenue has an issue I’ve been unable to resolve. Fuel pump died and I replaced it. Car ran fine for a week or 2 afterward, then intermittently wouldn’t start. When it WOULD start, it would idle fine but would bog on acceleration. I replaced the fuel pressure regulator as it appeared to be original (120k miles) and was corroded and looked like it may have leaked at some point. New regulator didn’t fix the issue. I checked the MAF and it looks new. I have no CEL. It runs, but has very poor throttle response off idle. Slow acceleration it does fine, but the harder you hit the gas pedal the worse it bogs and misses, and even dies occasionally).
Looking for some insights. I did a search here to try to track down possible issues, but things I’ve checked don’t seem to be the problem. I’m also changing the fuel filter, later today. Wondering if changing the fuel pump may have kicked some debris up clogged the filter (car ran great prior to fuel pump death).

What'* fuel pressure doing?

Currently, car turns over but won’t start. Fuel pressure at the test port shows around 55psi when I turn key ion, then I hear a click and it drops to around 45psi. It was in a similar “no start” state this morning, but started after I disconnected and reconnected the battery (coincidence?). Seems to act like a flaky sensor. Looking at live data on OBD2, MAF looks to be operating properly.

This, by itself, sounds like a clogged catalytic converter. Odd that this would happen with no check-engine light.

I wonder how the throttle position sensor performs on a meter with the engine stopped.

How many miles have you owned it?

I got the car from a cousin, whose parents bought it new. I’ve had it about a year but put less than 10k miles on it (so it’* very new to me). It’* been a great car, drives wonderful, and was dirt cheap.
TPS readings on OBD2 live data appear to be working well (runs from 0 to 100%).
Not sure if it matters, but the security check light flashes in the cabin. Maybe the isues I’m having with the car (going back to fuel pump replacement) was due to that? I haven’t tried to see if keys matter (I don’t even know how the security system works).. Main reason we replaced the pump was to fix the gauge as it was behaving VERY flaky), but that seemed to fix the running issues we were having at the time as well.
Would a bad crank or cam sensor produce codes? It’* the lack of codes that is puzzling me.

Brief update and new found issue?
Car is in a no start state. I tried both keys. One key it just turns over. The other key it seems to want to fire, but won’t start due to low battery (charging is in progress). I found another thread on here regarding a similar problem in a similar car, and that member found the issue was loose bolts holding the under hood fuse/relay box. So I thought I’d check that and low and behold, it has no bolts? What size fasteners go in those 3 holes, and could this be my problem?? See attached pic.

Like it is just dangling loose and you can move it all about?

Not exactly. The box has molded plastic clips that hold it in place, but I’ve seen mention that the bolts are what grounds it to the body. I’m going to try to find some bolts that work. Doubt it makes any difference, but it’* obviously supposed to be fastened.

I'd do the same. In absence of a known thing to fix a problem, fix the problem you know about and see if it helps.