Occasionly stall and refuse to idle

[ghrigter]

I have a Q 1995, with a problem. However, it is very intermittent. I changed the in-tank pump about a year ago.... no humming anymore in the back..... but occasionly... car stalls agin when hot and I have to rescue HRH my wife. I can drive the car home holding the RPM at about a 1000 After the car has been sitting overnight everything is fine again..... till the next time, what can be as far as 2 months apart. The problem is impossible to re-create by itself. Checked connections... Cleaned MAF etc. I cannot find the vacuum hose near the Throttle body as you describe... is it possible the sent a pic which shows the location.....? Thanks ahead! Gerrit

[ghrigter]

This is what I found when looking through the posts."Look at the hoses next to the throttle body, that hose that sits at a 90 degree angle. Is there a ninety degree angle in that hose? If not, it will cause a Q to idle at 500 roughly after warm up." I would love the have some more specific pointers or a photo where to find that hose.Thanx a lotGerrit

[goody90q45]

I have a Q 1995, with a problem. However, it is very intermittent. I changed the in-tank pump about a year ago.... no humming anymore in the back..... but occasionly... car stalls agin when hot....

Sounds like the humming fuel pump took out the fuel pump control unit (FPCU). Overheated it and burned up some solder connections. Our local Infiniti stealership has a statement on every parts invoice that the warranty is void on a new fuel pump if the FPCU is not replaced at the same time.

There's a few things you can do to verify this but since the problem is intermittent it may be tough.> Install a pressure gauge on the fuel inlet past the filter. Should read about 45psi (?) (if it wasn't intermittent).> Unplug the FPCU and ground out the fuel pump so it only runs in high speed. You should only do this for a few minutes/miles to verify the problem (if it wasn't so intermittent).> Buy a new FPCU for $600-$700 or a used one for about $60. Installation is easy. Remove the rear seat, pop up the rear deck, FPCU is held in by 2 bolts. Shouldn't take more than an hour.

Good Luck

[kevinjhk]

Hey Goody, you've got mail

[ghrigter]

Have forgotten to mention that just 14 days ago the Q passed the Californian smog check with flying colors! All measurements were way below average. There is another thing... whenever the car stalls... and I start several times.....I get a "low battery... " message. New battery..... checked charge ....+ 14.64 volts .... 12.73 at rest.... any suggestions?