2002 Q45 dies

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Aquaholic21
Posts: 30
Joined: Mon Apr 07, 2014 1:51 pm
Car: 2002 Q45

2002 Q45 dies

Postby Aquaholic21 » Thu Aug 08, 2019 2:35 pm

About to hit 200K miles. After driving about an hour in the heat the car will die...no codes, just dies. Not overheating, no warning. Let it cool down 20-30 mins and it will start right up and run fine. Any ideas?
:wtf2:


EdBwoy
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Location: St. Louis Metro East - IL
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Re: 2002 Q45 dies

Postby EdBwoy » Fri Aug 09, 2019 5:08 am

1. What happens if you attempt to restart it within this 20-30 minute cool down window, say start it 5 minutes (or even immediately) after it dies?
2. How does it die - drop in RPM stumbling and shutting or an abrupt cut of power?

That will help determine which of these likely ones is the culprit:
Fuel pump
Cam sensor
Crank sensor
Mass airflow sensor

You can eliminate the components whose replacement histories you are certain about.
Example - 02-q45-stalled-on-freeway-t621497.html

macgiver
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Joined: Wed Jul 04, 2007 10:21 am

Re: 2002 Q45 dies

Postby macgiver » Sat Aug 10, 2019 7:42 am

I betcha Edbwoy's right , first get a pressure gauge on the fuel rail , one you leave in there , preferably w long enough hose to duct tape to windshield low down , if you have to . The other three he mentions are of course next on the diagnosis - but are VERY expensive . Eliminate "fuel" first , gauge & a hose is CHEAP and good to have to boot . :yesnod

Aquaholic21
Posts: 30
Joined: Mon Apr 07, 2014 1:51 pm
Car: 2002 Q45

Re: 2002 Q45 dies

Postby Aquaholic21 » Wed Aug 14, 2019 7:04 am

Attempting to restart immediately will get it to crank only, waiting a few minutes will get it to fire, but not run for more than a second.

Abrupt cut in power is how it dies.

Background: last month had this issue, but turning off the A/C and the radio, it would run. Turned out the motor mounts were bad and tore a ground. Replaced the motor mounts and added a couple ground straps, been running great. It's rare to sit in traffic an hour, so haven't been able to replicate, but don't want my wife to drive it until I'm sure it won't die on her.

Is there a way to check the above sensors and see if they're on the way out?

This reminds me of when my 1968 Jeep got vapor lock when I took it in a 4th of July parade.

EdBwoy
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Joined: Tue Dec 25, 2012 12:47 am
Location: St. Louis Metro East - IL
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Re: 2002 Q45 dies

Postby EdBwoy » Sat Aug 17, 2019 7:10 am

You can take the sensor out and do some electrical tests as outlined in the service manual.
Another test you can do to isolate the camshaft sensor and keep the car running is to jab the gas pedal as you attempt to start it. In a situation that you said it would typically run but die shortly after, it could stay running.

Otherwise, as I usually say, if you have no history of its replacement, just go ahead and replace the camshaft sensor.
Your issues are typical symptoms of it, just like the link I posted earlier.

Aquaholic21
Posts: 30
Joined: Mon Apr 07, 2014 1:51 pm
Car: 2002 Q45

Re: 2002 Q45 dies

Postby Aquaholic21 » Fri Aug 23, 2019 2:48 pm

I've been able to duplicate the problem! No issues running down the road, but stopping in a parking lot, or center turn lane the car will sometimes die instead of idle.

Thank you EdBwoy, I'll be getting a gauge and ordering a cam sensor.

Does anyone have experience with these fuel pumps? https://www.fuelpumpfactory.com/product ... 20Shopping

I believe for sensors and such OEM is best, this fuel pump is so much cheaper than OEM.

macgiver
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Joined: Wed Jul 04, 2007 10:21 am

Re: 2002 Q45 dies

Postby macgiver » Fri Aug 23, 2019 3:44 pm

Keep in mind how these car's "Controllers" drop the voltage to F/pump considerably @ IDLE / Off idle . Mine goes full B+ battery voltage (less the power transistor junction drop) ABOVE 2k rpm's ('93 J30) , Q's will do this ,but I don't know if they have a "gradual' or "stepped" increases in power to F/pump - unlike my Big jump to FULL voltage after the 2k rpm!

So , a weak pump may not make it while "controlled on the down-Lo" , all these things I mention WILL show in
a pressure gauge tapped @ the rail . :crazy:

Aquaholic21
Posts: 30
Joined: Mon Apr 07, 2014 1:51 pm
Car: 2002 Q45

Re: 2002 Q45 dies

Postby Aquaholic21 » Tue Aug 27, 2019 2:23 pm

When trying to hook up the fuel pressure gauge, I found a vacuum hose that had been left off during the motor mount replacement (the small hose that goes into the large rubber intake hose on the engine side of the MAF.

Also used a found a P0340 cam sensor code.

The gauge didn't work so I don't know my fuel pressures (or we had the wrong line).

macgiver
Posts: 904
Joined: Wed Jul 04, 2007 10:21 am

Re: 2002 Q45 dies

Postby macgiver » Wed Aug 28, 2019 12:28 am

That goofy little hose , always comes off , and in the end never (J30 similar ?), for me ever been a source of a problem I was trying to diagnose. Cam sensor code is obviously significant , in lieu of whether or not you can get a F/pump up to "rail " pressure tested.


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