91 Maxima idles low and has NO acceleration

Hey Nissan lovers. I just bought my second Maxima (1991, VG30E,
automatic) at a charity auction and it's had this problem ever since.
When I can get it to start, it idles very low and when I step on the
accelerator, almost nothing happens....the tach just twitches a little.
Same story when I move the throttle under the hood by hand, so its not
the cable.

I get a code 55 from the ECU diagnostics mode 3 (code 55 = normal
operation). I've done all the ECCS sensor checks in the Haynes manual
and everything passes (though I know that doesn't mean they're really
working properly since the checks are so limited).

The distributor was worn out so I replaced it and I'm getting a good
spark. I checked the compression - its within range and the same in
all six cylinders. The fuel pump is ok, I replaced the fuel filter,
plugs, and the throttle valve switch, but still have the same problem.

**This is interesting - changing diagnostic modes on the ECU by turning
the screw caused the idle to normalize and allowed me to rev the engine
with the accelerator for about 20 seconds. I could only make this
happen 2 times while the engine was idling. Similarly, I changed the
modes without the engine running (just had the key at "ON") and my
buddy said he heard the injectors click.**

So I'm guessing one of the sensors is causing the ECU to not send power
to the injectors....or the ECU is no good. How can I find out what's
going on?? Tomorrow I'm going to check all the grounds and clean all
the connectors. Any other ideas or guidance? Please help.

jben wrote:

Hey Nissan lovers. I just bought my second Maxima (1991, VG30E,
automatic) at a charity auction and it's had this problem ever since.
When I can get it to start, it idles very low and when I step on the
accelerator, almost nothing happens....the tach just twitches a little.
Same story when I move the throttle under the hood by hand, so its not
the cable.

I get a code 55 from the ECU diagnostics mode 3 (code 55 = normal
operation). I've done all the ECCS sensor checks in the Haynes manual
and everything passes (though I know that doesn't mean they're really
working properly since the checks are so limited).

The distributor was worn out so I replaced it and I'm getting a good
spark. I checked the compression - its within range and the same in
all six cylinders. The fuel pump is ok, I replaced the fuel filter,
plugs, and the throttle valve switch, but still have the same problem.

**This is interesting - changing diagnostic modes on the ECU by turning
the screw caused the idle to normalize and allowed me to rev the engine
with the accelerator for about 20 seconds. I could only make this
happen 2 times while the engine was idling. Similarly, I changed the
modes without the engine running (just had the key at "ON") and my
buddy said he heard the injectors click.**

So I'm guessing one of the sensors is causing the ECU to not send power
to the injectors....or the ECU is no good. How can I find out what's
going on?? Tomorrow I'm going to check all the grounds and clean all
the connectors. Any other ideas or guidance? Please help.

My *guess* (educated, I suppose) is that you have a a bad mass airflow
sensor...

Nirav

jben wrote:

Hey Nissan lovers. I just bought my second Maxima (1991, VG30E,
automatic) at a charity auction and it's had this problem ever since.
When I can get it to start, it idles very low and when I step on the
accelerator, almost nothing happens....the tach just twitches a little.
Same story when I move the throttle under the hood by hand, so its not
the cable.

I get a code 55 from the ECU diagnostics mode 3 (code 55 = normal
operation). I've done all the ECCS sensor checks in the Haynes manual
and everything passes (though I know that doesn't mean they're really
working properly since the checks are so limited).

The distributor was worn out so I replaced it and I'm getting a good
spark. I checked the compression - its within range and the same in
all six cylinders. The fuel pump is ok, I replaced the fuel filter,
plugs, and the throttle valve switch, but still have the same problem.

**This is interesting - changing diagnostic modes on the ECU by turning
the screw caused the idle to normalize and allowed me to rev the engine
with the accelerator for about 20 seconds. I could only make this
happen 2 times while the engine was idling. Similarly, I changed the
modes without the engine running (just had the key at "ON") and my
buddy said he heard the injectors click.**

So I'm guessing one of the sensors is causing the ECU to not send power
to the injectors....or the ECU is no good. How can I find out what's
going on?? Tomorrow I'm going to check all the grounds and clean all
the connectors. Any other ideas or guidance? Please help.

If this motor has a knock sensor I would check that.

CD

Hi Jben

i also had exactly the same problem,
but this satarted to me when i took my nissan maxima(1998) to manineke
to check for the rattle sound under neath the car.
that crazy guy , i dont know what he did , since i had,
surpringly, it picks up pretty fast and ome time it picks up with some
lag, when i press the gas pedel.

i am assuming there is some kind of leak in my exhaust pipe,
may be this might causing the lag in the pickup(sometimes) when the car
starts rolling, when it is in motion, i dont have any problem.
but roar noise between 65-75 (again not always).

let me also know how you fixed ur problem.

it matches exavtly to my problem too.

i am not that good in cars.
this is my first car in US.

jben wrote:

Hey Nissan lovers. I just bought my second Maxima (1991, VG30E,
automatic) at a charity auction and it's had this problem ever since.
When I can get it to start, it idles very low and when I step on the
accelerator, almost nothing happens....the tach just twitches a little.
Same story when I move the throttle under the hood by hand, so its not
the cable.

I get a code 55 from the ECU diagnostics mode 3 (code 55 = normal
operation). I've done all the ECCS sensor checks in the Haynes manual
and everything passes (though I know that doesn't mean they're really
working properly since the checks are so limited).

The distributor was worn out so I replaced it and I'm getting a good
spark. I checked the compression - its within range and the same in
all six cylinders. The fuel pump is ok, I replaced the fuel filter,
plugs, and the throttle valve switch, but still have the same problem.

**This is interesting - changing diagnostic modes on the ECU by turning
the screw caused the idle to normalize and allowed me to rev the engine
with the accelerator for about 20 seconds. I could only make this
happen 2 times while the engine was idling. Similarly, I changed the
modes without the engine running (just had the key at "ON") and my
buddy said he heard the injectors click.**

So I'm guessing one of the sensors is causing the ECU to not send power
to the injectors....or the ECU is no good. How can I find out what's
going on?? Tomorrow I'm going to check all the grounds and clean all
the connectors. Any other ideas or guidance? Please help.