Engine won't rev past 2500 RPM

[Francis01]

I just bought a 2001 Nissan Pathfinder LE that's reasonably low mileage, but it's problem is that its engine chokes out around 2500 RPM, whether it's driving or in park. There's no check engine light on. Any ideas what's going on here, as I'm starting to work on it?

My initial thought was that this had something to do with the fuel system (bad pump, clogged fuel filter) and I've actually ordered a new fuel pump, but as I've been poking around, it seems like a handful of people have run into problems like this on other vehicles when the ECM fuse blows. I've also seen people suggest a dirty/bad CAS or a bad MAF. The ECM fuse looks ok, initially, but I don't know my way around the electrical system well enough to rule out the ECM more generally. I'm going to try to get some sensor cleaner today.

Any other recommendations for what I should be looking at from someone who has actually worked on these vehicles before?

Thanks, in advance, for the help!

[Francis01]

Ok, so as an update, it was actually a really simple problem: the MAF was unplugged. I now know I have a different problem--the check engine light bulb must be burned out.

[MisterH]

Good that you made progress. If you don't already have one it would be essential you have a scan tool so you can tell what's going on - even if the CEL light is missing. Sorry to sound overly cynical but sadly there are unscrupulous sellers who have simply snipped one of the leads to the CEL in an attempt to sell a car with significant problems. Hope yours isn't one of them.

[Francis01]

Thanks, MH. Done -- and now trying to sort out a couple other issues.

[Hawairish]

The CEL/SES light illuminates for the 1st few seconds after start up, regardless of a code being present. This is true for every OBDII vehicle. If it doesn't, then the bulb is out or removed.