Car Won't Start; Replace Coil Packs?

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Q451990
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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 don't think the cylinders would hold fuel forever. The fuel will seep past the rings and into the crankcase/oil sitting overnight. I'd change the oil when you're done with all of this. It wouldn't hurt to check the oil level just to be sure it's not overfilled, if by chance you had a massive amount of fuel leak in to the crankcase (unlikely). As a side note, you may have a rough or bouncy idle for a little while if you had fuel wash the oil off of your cylinder rings, because you won't have compression on that cylinder until the oil gets back on to the cylinder walls and helps those rings seal.

Here's the TSB that I mentioned. There's a graph that gives a good feel for what's normal with fuel pressure leaking down. I would probably skip trying to pinch off fuel hoses unless you detect a leak. Then you'd want to pinch off the return line to see if that's your problem. Or you could use a small scrap of hose with a bolt clamped in to it as a plug for the outlet at the rail, to avoid clamping and possibly damaging the fuel line.

The TSB and old thread is for the 90-96 series of Q, but I would think the specs are about the same for all of the Nissan side-feed style injectors.

https://drive.google.com/file/d/0B-M9Hn ... y=CJHR2qkF

Here's an old thread talking about testing the rails off of the car.
testing-injector-seals-in-the-rail-coul ... 66243.html

And here's a pretty good Youtube video of a guy doing it on his Frontier.
https://www.youtube.com/watch?v=qJ7L9aqEcfM


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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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Engine Cont. would be the ECU. Cranking would be about 5-10 seconds continuous starter action one time.

my12by60
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Location: Fountain Hills, AZ

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I am hesitant to declare victory until we drive some more miles. Looks like the OEM injector was possibly stuck open. The pressure tester showed pressure loss almost immediately every time I cycled the key to "on" with the OEM injector installed. I changed out the OEM injector and put in the new cheapie injector that I bought on Amazon. When I tested the pressure with the new injector, I was getting no pressure reading at all. I think something was wrong with the pressure tester. I guess $16 does not get you a top quality tool. I decided to remove the tester from the line and just see what the car would do with the new injector installed. So far, so good. The car is idling well and ran fine on a four or five mile run around the neighborhood. My son has it out now. So I will get another report when he gets back. I cleared the trouble codes before I went out for a drive and no codes have reappeared yet. Thanks for all of the help to get me to this point.

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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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Sounds like progress!

my12by60
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Joined: Sun Nov 22, 2015 10:32 pm
Location: Fountain Hills, AZ

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I think the case is closed. My son has been used the car all weekend and the SES light is not back on the car is driving well. I learned a good bit about how the fuel system works and did not ruin the engine along the way. So the DIY project was a success.

maxnix
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Joined: Mon Jul 22, 2002 8:11 pm
Car: 1995 Infiniti Q45
1995 Infiniti Q45t
2000 Infiniti Q45

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Please don't experiment until you know that there is no hydrolock.
I lost an engine that way when a "reputable" injector cleaning firm did not pressure test them after the injectors were mounted in the fuel rail.

Buying any cheap auto part off eBay is not a good strategy for maintaining a functional automobile, either. The Chinese have become very good at replicating packaging and looking like genuine that do not work. Be sure to source critical parts (ones that will total your car or engine) from reputable sources. If the price is to good to be true, there is a big red flag waving in front of your face.

maxnix
Posts: 22628
Joined: Mon Jul 22, 2002 8:11 pm
Car: 1995 Infiniti Q45
1995 Infiniti Q45t
2000 Infiniti Q45

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I'd change the oil when you're done with all of this.
At least look at it and sniff it. Any hint of Gasoline, new oil and filter immediately.

Fuel line filter changed this year or last 12K miles?


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