95 Q45 Weird Idle

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Gingermanbread
Posts: 8
Joined: Sat Oct 16, 2010 8:21 pm
Car: 1995 Infiniti Q45
Location: Wichita, Kansas

Post

Alright... I just changed the spark plugs on my 95 Q45, and now the idle's not holding correctly. It bounces up and down about 100-200 rpms when idling, and I can feel it and hear it throughout the car.

Any suggestions?


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goody90q45
Posts: 3679
Joined: Wed Aug 17, 2005 2:07 pm
Car: 1992 Q45 (sold)
Location: Orangevale, CA

Post

It sounds like something didn't get reconnected.

Is the mass air flow sensor connection clean and the pins tight? Did all the hoses get hooked up especially the large one venting the valve covers and going to the bottom of the air tube past the MAF?

Gingermanbread
Posts: 8
Joined: Sat Oct 16, 2010 8:21 pm
Car: 1995 Infiniti Q45
Location: Wichita, Kansas

Post

Yeah, everything got hooked back up, we were really careful about it.
The guy who did it for me says that the old plugs were rusted so bad that my car would have only been firing on 4 or 5 cylinders now, and now that the engine has more power, it's firing harder. He thinks it's either the engine mount or the fuel injectors.

What weirds me out more is that the 'transmission malfunction' message is just now coming up on screen, but it's still doing that hard shifting stuff that I posted about earlier, which makes me think that my car just now figured out what the issue is.

qship96
Posts: 6624
Joined: Sun Nov 24, 2002 11:31 am
Car: 1996 Q45

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car ran fine until you had someone change the plugs......then a problem..........guess where the real root of the problem is?????

Gingermanbread
Posts: 8
Joined: Sat Oct 16, 2010 8:21 pm
Car: 1995 Infiniti Q45
Location: Wichita, Kansas

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Haha, yeah, that's what we're thinking...
They came pregapped, and we didn't really check them over too well to make sure that they were gapped... Ugh.
Guess I know what I'm doing when I get home from school tomorrow.

Even if it is the plugs, that still doesn't explain the 'transmission malfunction' message that's coming up now. I knew it was shifting hard before, but I don't think that the plugs should have anything to do with it. :/

qship96
Posts: 6624
Joined: Sun Nov 24, 2002 11:31 am
Car: 1996 Q45

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I meant the installers quality of work, not the plugs!!!! something was knocked loose or left unconnected- check all wiring harnesses very carefully- it is easy to crack one of the old brittle connectors causing a poor electrical connection also!

Gingermanbread
Posts: 8
Joined: Sat Oct 16, 2010 8:21 pm
Car: 1995 Infiniti Q45
Location: Wichita, Kansas

Post

That's a good starting point for my search... Appreciate the help!
I'd still like to know where the transmission malfunction error is coming from, but that might just be a byproduct of some fault in the system somewhere... I dunno.

I'll check them out tomorrow after school, and I think I might just take the car somewhere to get the transmission serviced. I just haven't had any luck with this thing, so I think I'd feel safer putting it into a professional's hands at this point.

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Q451990
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Posts: 11473
Joined: Tue Jul 23, 2002 8:21 am
Car: 1990 Q45 - 118K, 2022 Toyota 4 Runner, 2004 Frontier M/T - 108K, 2012 Xterra (Mom's), 2023 Rogue (Inlaws)
Location: Columbia, SC
Contact:

Post

I hope you took those Bosch plugs back and got the factory specified NGKs.

Heath

Gingermanbread
Posts: 8
Joined: Sat Oct 16, 2010 8:21 pm
Car: 1995 Infiniti Q45
Location: Wichita, Kansas

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I ended up with Autolites, I hadn't seen any complaints about them on the forums.

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Q451990
Moderator
Posts: 11473
Joined: Tue Jul 23, 2002 8:21 am
Car: 1990 Q45 - 118K, 2022 Toyota 4 Runner, 2004 Frontier M/T - 108K, 2012 Xterra (Mom's), 2023 Rogue (Inlaws)
Location: Columbia, SC
Contact:

Post

Arrrrrrg :(

OEM NGK :facepalm:
OEM NGK :facepalm:
OEM NGK :facepalm:

Gingermanbread
Posts: 8
Joined: Sat Oct 16, 2010 8:21 pm
Car: 1995 Infiniti Q45
Location: Wichita, Kansas

Post

Got the idle all sorted out, there was a plug that didn't get set quite right...
And so far my Autolites have been good! My tranny's even shifting a bit smoother right now...
But I'll take it in and get it serviced and checked up 100% asap.

If my car acts funky again though, I know where to start, and I'll switch over to NGKs.

Now just for the rest of the stuff!


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