Rough Idle condition with my 97 "Poopty"

[Tai Maishu]

I know it seems like a topic that would be more at home on the "engines specific" forum, but considering it only has to do with VQ's, RB's, SR's & QR's, I figure I might have better luck reaching out to other Sentra owners. I have a 97 B14 with a GA16 and an automatic (BOO!) trans. Just today, while out to run errands (like putting in gas?!), I noticed it started to idle funny. I started to get the tell-tale "shake" and I knew I had a problem. I knew it was a rough idle, but it would go away if I was at speed. After driving it a little more, the problems got worse; instead of a rough idle condition, my car started to "de-rate" itself. That's when I knew I had a problem, least among which was the fact the "check engine" light came on. I was only down the road from my house (thank god!), but I still had to make the climb uphill to get it back home; I barely made it. So now I have to figure out what went wrong and what I can do to fix it. As I plan to go back to work soon and need a car to get there, I need to get to the bottom of this. So if anyone can give me any idea of what to look for, or what to do, that would be greatly appreciated. Thanks.

[Noxy]

Did it sound like a misfire, or was it really loping at idle? If you could pull the code(s) from the ECU that might tell you, or help.

My old GA16 MAF sensor kept getting disconnected and would act similar until I replaced the clip. I would start with checking all of the electrical connectors first and make sure they're all attached, then look for deteriorated vacuum hoses around the intake manifold and valve cover area.

If all of those look good and are connected then check the symptom matrix chart on pages EC-315 and EC-316 of the FSM here:

http://www.nicoclub.com/FSM/Sentra/1997_Sentra/ec.pdf

The black dots mark likely causes, and should be checked first.

Let me know how it goes!

[Tai Maishu]

Thanks for replying! Yeah, it did make a loping noise, and then as I started to make my way home (I live on a hill), the ECU started to de-rate the engine and when it did that, I think it may have misfired. I say "I think" because I'm not sure if it actually did. Everyone has said to check the MAF Sensor and vacuum hoses and I'll begin my search there. BTW, thanks for the resource; been trying to look for it last week.

P.S. Sorry about your rather "colorful" history with cars. I've had an experience with a chop shop operation before and it sucks! Hope the future gets better.

[Noxy]

No problem keep us (or me as this forum section seems to be going lately haha) updated!

Yeah, my luck with cars has been pretty bad the last couple years. I'm in the same boat as you diagnosing my 2004 Sentra...

[Tai Maishu]

Alright, so I've disconnected every single *visible* sensor and pretty much all I've been able to do was turn the check engine light off (really, it hasn't even come back on while running)! It still runs horribly so now I'm wondering if my ignition timing is off or possibly a weak/no spark condition with one (or more) of the cylinders, or worse, a "dripping" injector? I've checked the vacuum diagram on the hood and I didn't really see any hoses that were bad, but then again, I haven't gone over them with soapy water (yet). I'll keep checking, but as much as I love her, if I can't get it running again by January, she's going to be scrapped. It's costing me too much money just for it to be used as a driveway ornament (and a portable rain catcher).