Bad gas in a QX4

[adonis_mouse]

Hi all,

My friend's '97 QX4 was sitting for 9 months without being started. Charged up battery and she turned over pretty good, but I guess the old gas in the system wasn't the best thing.

In a nutshell: lots of stalling, some juddering, but mostly okay. I've changed the fuel filter and that seemed to help. She goes pretty good and can go an hour without problems, but will then stall several times in a short period of time out of the blue. Or sometimes judders heavily if the revs go above 2200, but other times that's perfectly fine also.

Gunk in the fuel lines? Something to do with the pump? Any tips on what else I can do?

Cheers!

[macgiver]

mac,How much gas ? Really gotta take it in ,get flushed and FULL procedure at a decent shop to get the BAD stuff completely out - for it sounds like a right & proper car left out too long & stagnating the fuel in the tank.
My other car needs head gasket - sitting for 2years - whatcha gotta do is only keep like 3 gals,use a fuel stabilizer & maybe ounce of "Mystery oil" , maybe 4 ounces fuel system clean ( be sure safe rated for Cats &O2's) and even I don't believe in fuel additives , but a special "situation" here - long storing vehicles.And mine still ran (drain coolant + new oil etc.) THAT"S the KEY gotta start everyweek to 10 days for battery ,oil, trans fluid flowing etc. And if not running you simply try to add w/gas can a gallon WITH the "Stabilizer" every 2 months;
Otherwize - your situation entails. Good luck G

[nickelghandi]

You might have other issues present. Do you have any engine lights?

[adonis_mouse]

Took her out this weekend, did 200 miles. Goes up to highway speed no problem. Revs well most of the time. New gas in the system seems to help. But still stalls every now and then - then will run an hour no problem.

Apart from change fuel filter and gas her up haven't done anything else. Same oil, same fluids as she had in her 10 months ago. Tires even stayed up.

Testament to something or other.

[BubbaFL]

If you've gone a few hundred miles, changed the fuel filter, and refilled the tank, it is not likely there would be enough bad gas in the system to continue causing problems.

I've had similar intermittent issues with my QX4.

I'd suggest a fuel pressure test, and check for pending trouble codes, if you have access to the right equipment.

Take a look at my video in this thread to see what mine was doing:

vq35de-surging-misfiring-under-load-t619983.html

[adonis_mouse]

Thanks for that. It doesn't sound quite the same but interesting to read the thread.

Did you get it sorted?

[BubbaFL]

Not entirely sure. Tough to diagnose a problem that is very intermittent and doesn't set codes. I threw a fuel pump and filter at it. If the problem happens again I'll know it's something else.

[adonis_mouse]

Ah. So you haven't had the problem since you changed the filter and the pump?