1995 Altima GXE wont stay running.....

[Slownis]

Someone on the Altima forum sent me here, so you guys come highly recommended. Here is a vid of the problem I'm having:

http://www.youtube.com/watch?v=SOL-9DbkxLk

So as you can see, I can get it started, but if I touch the throttle, it usually dies.

Its not the main engine ground.
Its not throwing any codes and the CEL is not on.
Fuel is flowing - obviously or it wouldn't start.
Fuel filter recently changed.
Any ideas?

 

[tomcat27]

I usually start with the basics. do you have or can you borrow a fuel pressure tester? not sure of the spec for your car but i'd look for at least 40 psi on the fuel rail. how many miles?

 

[dtt004]

Hi.

In my opinion, the induction system should be examined. Throttle body assembly and idle control system. If the engine is doing this when it is cold, it will probably be the idle control system. If it is doing it all the time, then there is a serious problem with your engine. I can't put a finger on it right now unfortunately.

 

[Steve S]

You need a service manual.

 

[Towncivilian]

FSM: http://www.nicoclub.com/FSM/Altima/1995/

Perhaps try cleaning the throttle body & MAF sensor?

 

[Slownis]

Ya, I've already got the Nissan Service Manual for it - the same link that Towncivilian posted. Thanks anyways.

Car has about 150k miles on it. I don't have a fuel pressure tester. There's no shrader valve to test it with, I'd have to T-in. That wouldn't be much of a problem, but.....

I already went through the trouble of pulling out the fuel pump. I'm going to change it out and see if that fixes it, but I'm not confident it will work. If not I'll try cleaning both the MAF and the throttle body. I've never seen a dirty throttle body cause a car to die so easily - usually just run rough.... but we'll see.

 

[beaker60]

Hey SLOW,,,TPS,,,aka,,throttle position sensor,,,they go out a lot,,,also,,if you can get your hands on or borrow a scan tool,,you can monitor all of the sensors.I just worked on an Altima that just about drove me nuts,,,doing the same thing,,,turned out to be both,,,the cam position sensor and crank position sensor,,but I would start with the TPS,,hope this helps

 

[Slownis]

I've already got the scan tool. No codes.

Cam and crank sensor problems "should" throw a code.

I'll look into the TPS.

Cam and crank sensor codes usually indicate the need for a new distributer in these cars, BTW.

For now I've held off getting a new fuel pump because I don't have $200 to drop on it without knowing for sure. I took the safe rout here and I picked up a $25 fuel pressure tester. I'm going to put the old one back in and try it out today.

 

[lairdwd]

I have seen the 1st gen altima throw a code for TPS voltage out of spec. Not sure what it does in other failure scenerios.

Have you tried to disconnect maf, tps? ... Can u even try to unplug IACV?

I think you can get a cheap consult board on ebay.

 

[sunfire]

Vacuum leaks? Did you check your hoses for leaks?

 

[Vikas]

OK, let us try to approach this logically rather than throwing parts at it.

If it starts but dies when you give the gas or when put the load on the engine, you need to ascertain as to how it is dying.

If if dies with a gasp, then it is not getting any fuel. It it dies suddenly without any protest, then it is not getting any spark.

The ECM needs some specific signals to keep the fuel pump and ignition going. Those signals are bypassed when you crank the car using starter. When the car starts but dies and can not be kept running by fiddling with the gas pedal, it means your ECM thinks the car is not running and is cutting off the fuel and/or ignition. This system is designed so that when you crash the car, the fuel pump stops running even when the key is in ON position. Ford uses inertia switch in the trunk. How does Nissan handle this case?

Hopefully, somebody who is more familiar with the car's electrical system might be able to use these hints. Some of the anti-theft systems are designed like this i.e. allow car to start but not go anywhere.

- Vikas

 

[Slownis]

Thanks for all the input guys. Problem is solved. I hooked up the fuel pressure guage I bought and it looked good. Then my neighbor came over with his top of the line code reader that gives live readings. Again, everything checked out. I even let it idle for half an hour, everything was good. I also cleaned the MAF, and the throttle body. Finally, we used my neighbors spark tester and tried it on each of the spark plug wires. By using this, we were able to diagnose a bad distributor cap and rotor. I replaced these two parts, along with the wires I broke trying to get them off, and everything is good now.

Thanks again!