1997 Q45 ignition condenser location

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houstonvett
Posts: 2
Joined: Mon Nov 06, 2017 7:29 am
Car: 1997 Q45

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Working on the Q45 and it is running rough. Checking the coil packs they OHM out fine but I am having a hard time finding the ignition condenser itself. Not much information on the net about the condensers location, just seeing if anyone here in this great Forum knows of it's location. I have seen on a few Nissan vehicles the condenser is located in the front of the engine harness all taped up and hard to spot. Any help would be greatly appreciated. TIA


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Q451990
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Posts: 11472
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
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I know the transistors are built in to the coil packs. The factory service manual is available at www.infinitiservicemanual.com, so you might check there. Roving coil pack failures are common on that series of Q, and the most reliable solution appears to be replacing all eight with new factory or Hitachi packs.

houstonvett
Posts: 2
Joined: Mon Nov 06, 2017 7:29 am
Car: 1997 Q45

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The capacitor ignition coil is separate then the coil packs. This piece is designed to store voltage, keeping it constant in the voltage feed line to the coils. In this way the ECM can monitor the resistance of the feed line to the coil packs and throw a code if the resistance gets too high, which might indicate a coil pack going south. This little unit is an important piece and well worth changing if you are having ignition problems with your Infiniti. The capacitor ignition coil is part Infiniti # 2835189902. This piece can be had at a Nissan dealer also as they are used in multiple Nissan vehicles also.

Now Infiniti and Nissan both do a good job of hiding this coil and took a while of searching before I found it. It is included in the wiring harness itself and is factory taped around the harness, so it is hard to see. On this Q45, it is located on the passenger side of the engine, taped to the large wiring loom running done the engine and feeding the injector and coil packs. It will be at the back of the engine (on the 45) and be right on top of the loom. You should see a small wire harness coming out of the larger loom and folding back onto itself and that where the condenser is located. Cut off some of the loom tape and you will see the capacitor and it's associated plug. The old capacitor was in bad shape and was breaking apart when trying to break the connector loose from the capacitor. Be very careful because these connectors are very fragile after living in high heat conditions all of these years.
This should help you get rid of the P3012 code and any knock sensor codes that were set when the ignition problems were occurring. The capacitor was about 9.00 from the dealer, well worth the price.

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Q451990
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Posts: 11472
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:

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Good information!

I did some searching because I didn't remember hearing about this part before... apparently I did about 4 years ago. :rolleyes:

condenser-location-t580055.html

So this fixed the misfire issue on your Q?

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chipahoy
Posts: 98
Joined: Mon Oct 10, 2011 2:24 pm
Car: 1999 Infiniti Q45T, 250,000k
Location: Miami, Florida

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changed the valve cover gasket and now car is running rough. got the P1140 code and purchased the Ignition Condenser Coil online. Still having trouble locating it. spent 30 minutes searching manual with no success. is this part called something else by Nissan?

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chipahoy
Posts: 98
Joined: Mon Oct 10, 2011 2:24 pm
Car: 1999 Infiniti Q45T, 250,000k
Location: Miami, Florida

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Make sure that when you purchase the part you provide the VIN to the retailer. there are two different ignition coil condenser models/suppliers depending on the manufacturing date of the vehicle.


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