# sentra hard start, no fuel until wot



## studentmechanic101 (Jan 13, 2007)

Hi everyone, I have been looking all over this board and i cant find anyone with the same problem. I have a 1994 sentra xe with the 1.6. So far I have only had the car while it has been cold and the only way to start it when it is cold is to put the gas pedal to the floor. After the car has started you can shut it off right away and it will immediately start right back up without touching the gas. It runs perfect too! I have cranked it without the pedal to the floor and then pulled the plugs and they were dry. I have put in a new set of plugs and a new fuel pressure regulator. Hopefully someone can give me a good idea to go with, thanks, Matt.


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## MisterRx (Feb 8, 2006)

Check the condition of the fuel pressure regulator vacuum hose, it might need to be replaced.

Check the condition of the battery by measuring the voltage under load.

Check fuel filter.

Starting Procedure

Turn the key to "on" wait 10 sec. and then turn the key to "start". The delay will allow the fuel pump to build up the pressure needed. If the engine fire ok then the problem is with fuel pressure.

other tricks

Remove fuel pump fuse, crank the engine couple of times, put back the fuse, then the engine will start.

Press the throttle about 1/2 open. Release then start the car. Carbon buildup on the butterfly, this will break the bond. If this works clean the throttle plate(butterfly plate)


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## MisterRx (Feb 8, 2006)

I was reading a post that said Faulty Temperature Sensor (Sensor that indicates when it's cold to add more fuel to start your car). Probably Coolant Temperature Sensor??? or something else.


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## studentmechanic101 (Jan 13, 2007)

Is their anyway that this could even be the fuel pump? It just makes no sense that it wont work when the car is cold but when it is warm it works just fine. Thanks again, Matt.


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## b13pnoysentra (Mar 30, 2005)

I used to have this problem before. When it's really cold in the mornings, my car would crank, but then it would putt and shut off. I had to step on the throttle in order for it to fully start. It started fine when it was warm. The problems started when I changed my stock intake box to a short ram intake kit from ebay. I figured it must have been some kinda of vacuum leak due to the installation of that kit, so I searched around and finally decided to change the PCV valve (suggestions from a few members last year). This part was really cheap, but it fixed the problem ever since. I also change the short ram back to the stock tube and kept the cone filter.


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## studentmechanic101 (Jan 13, 2007)

Were you getting gas when you would crank it over? because when I cranked it over I would crank it for like 15 seconds and pull out a plug and it would be dry. So I think the only time I am ever getting gas is when I had it to the floor. But any ideas would be great because I think I might put in a fuel pump but I really dont know what to do next. Thanks again, Matt.


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## MisterRx (Feb 8, 2006)

A good quality fuel pump (brand Carter) will cost $300 Canadian plus installation. When you turn the the key partially do you hear fuel pump noise in the back (tank)? Old Sentra are known for fuel pump problem but is costly repair if you make wrong decision.

My 92 Sentra was parked on second floor of shopping mall, vibration to the floor caused my fuel pump to stop. I could crank the car but the engine would not stay running even though I pressed the gas pedal. I barely managed to get the engine running when I got to the first stop sign the engine stopped. I couldn't get it started. Passerby helped me out. He pressed gas and brake back and fourth and finally got the engine started. I replaced the fuel pump, didn't have problem yet. Your problem doesn't sound like mine.

Accord and Civic had a problem with intermittent starting and it turned out be Main Relay located underneath the dashboard. What Main Relay does is activate the fuel pump. You can do a search with ( Fuel Pump Relay, Sentra). If there is known problem with fuel pump relay? Less costly if it is the cause! I think the Fuel Pump Relay is located near the battery. By the way my brother tested the Main Relay with 12 Volt from the car battery and found it to be defective.

(Might) Check the Blue Relay next to fuse box. Try interchanging the bottom two Blue Relay. There are two Relay associated with Ignition


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## studentmechanic101 (Jan 13, 2007)

well I replaced the pcv valve with no luck. Next I will try to replace those relays or switch them around. where exactly is the main relay that you were talking about? I think that the fuel pump is running because it will start right as you put the gas to the floor and it will stay running and it will run perfect too. Thanks, Matt


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## MisterRx (Feb 8, 2006)

Main Relay is the terminology used by Honda, they have their Main Relay under the dashboard. Drives the fuel pump. Nissan doesn't use the same terminology but assume it is the Fuel Pump Relay near the battery.


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## MisterRx (Feb 8, 2006)

To determine if the Inhibitor Relay also known a Clutch Inhibitor Relay also known as Clutch Interlock Relay is defective switch it around with identical part number Fan Relay or another Relay. These Relays are Blue in colour. I beleive Inhibitor Relay is connected to the Starter and sometimes causes starting problem.


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## studentmechanic101 (Jan 13, 2007)

Well I have replaced the fuel pump relay with no luck. I found out that I dont have to put it to the floor, it will start if you put it about half or three fourths of the way down. When I turn the key on I can here the fuel pump turn on and if I turn the key on and off and cycle the pump to build pressure it still does the same thing. Thanks, Matt.


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## MisterRx (Feb 8, 2006)

Pressing on gas pedal means opening up throttle. Maybe you should check the condition of air filter if its clogged up.

Other cheap tricks disconnnect the battery, wait 15 min, reconnect the battery. Initializes the computer.

Other thing you could do is clean the Idle Air Control Valve with Carb. Cleaner and Q-Tips. Searching the this website will tell you how to do it.


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