Ok, I think I have my problem narrowed down to the coolant temp
sensor. I know of two sensors in the coolant itself not counting the
temp sending unit. ONe is located in the intake manifold and there is
another sensor in the lower radiator hose. Does anyone know what these
are and which one is the coolant temp sensor or are they both temp
sensors. I get a MAL 13 on the ECU..........

Would a bad temp sensor also account for a lot of gas usage?

Regards
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Roy aka Chipmaker // Foxeye
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Remove capital A from chipmAkr for correct email address

On Thu, 10 Jul 2003 01:50:15 GMT, Roy Hauer <chipmAkr (AT) hotmail (DOT) com>
wrote:

The one with two leads on the maniflod is the ECU engine temp sensor,
this is the sensor that gives a code 13. The one in the hose is for
the fan - it switches on when the rad outlet water is too hot.

--
Peter Hill
Spamtrap reply domain as per NNTP-Posting-Host in header
Can of worms - what every fisherman wants.
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I'm not sure about that but a leaky injector or two would certainly account
for lots of extra gas usage.


-BD

Roy Hauer <chipmAkr (AT) hotmail (DOT) com> wrote


if the ECU thinks the engine is always cold, it will not go into
closed loop control and therefore use more gas.

Roy,
The Engine Coolant Temperature sensor could be one of the reasons for
poor gas mileage. ECU uses signal from the Engine Coolant Temperature
sensor to feed extra fuel into the intake to warm the engine up when
cold - primarily for emissions control.

You might also want to check your Oxygen sensor located on the exhaust
manifold piping. Since you are familiar with the www.240SX.org website,
just go to the site and click on the FAQ button. The FAQ page lists
procedures on how to check the Oxygen sensor. You also might want to do
a tune up while you are at it. Swap out the distributor cap & rotor,
change the sparkplugs, (NGK's always seem to work best for me), pour a
bottle of fuel injector cleaner in the gas tank, and spray carburator
cleaner into the intake throttle body and clean out the electrical
contacts leading to the Mass Air Flow Sensor and Engine Coolant
Temperature Sensor. The contacts often get dirty with oxidation causing
a poor signal to lead to the ECU - lubricating them with di-electric
grease tends to help a lot. You might also want to check the stock air
filter while you are at it also.

Hope this helps...
ID
'95 240SX SE

Roy Hauer wrote:

Appreciate it.
I just changed the coolant temp sensor out. Just starting it up after
seemed like a totally different car.Time will tell. SInce this is my
youngins vehicle, I will have to wait until he comes back around my
place (currently under orders from headquarters to park it and wallk
or get a job and get tires replaced)......You may know how things like
that are. I had agreed to see what I could do to get his $500 car
running since without a car he could not look for a job.......so its
running now, not overheating, and its got about a 1/2 tank of fuel.
Before it blew a lot of black smoke etc now it does not, and it
actually idles nice and smooth. Next time I will check the O2 sensor
though. He put plugs in it, and replaced the wires,(el cheapo stuff,
and I know the plugs certainly were not NGK) His so called
mechanicallly inclined friends told him all it needed was plugs and
wires and it should be ok after a tank or two of premium gas.yea,
right. All they were looking for was a ride anyhow...... I think 1/2
of his tank of fuel is fuel injector cleaner though ;-) It should have
the cleanest injectors and fuel system found anywhere.

He actually made an attempt to clean his butterfly etc in the intake
throttle body.only thing is he used brake cleaner because he did not
have any carb or injector cleaner to use at that time.sorry thing is
the brake cleaner stated "NON-Flammable forumla.......and he really
loaded it up pretty bad.....duh! But it certainly did make it pretty
darn clean.

Still waiting for the stock of manuals to come in at Barnes & NObles,
so at least I have a few pictures to see what exactly I am working on
or looking for. The 240sx website has certainly been a great help, and
once again thank you for pointing me to that website. My era of cars
were the ones that had a PVC valve as the entire means of poltution
control and fuel injection was only on the corvette.Never tinkered
with imports other than an old VW diesel, and presently have a Toyota
(the wifes) and dread the day something happens to it. Oil changes etc
are not a problem or something plian and simple and obvious, its these
sensors and how they inter relate with each other and what does what
that confuses me, but I see a light at the end of the tunnel now, as i
have been learning something about the systems by tinkering with this
vehicle and the 240sx site.
Once again, thanks a million

On Sat, 12 Jul 2003 19:15:45 GMT, DELETE-ID
<DELETETHISidlafie (AT) REMOVETHISearthlink (DOT) net> wrote:

--
Visit my website:
http://www.frugalmachinist.com
Contents: foundry and general metal working and lots of related projects.
Regards
Roy aka Chipmaker // Foxeye
Opinions are strictly those of my wife....I have had no input whatsoever.
Remove capital A from chipmAkr for correct email address

On Sat, 12 Jul 2003 21:17:51 GMT, Roy Hauer <chipmAkr (AT) hotmail (DOT) com>
wrote:

Never seen a set of Jap leads that actually needed to be replaced
unless abused by user. The aftermarket stuff is always of lower spec.

Never used anything other than NGK since the time I bought a Champion
and brand new it was worse than the old NGK.

Nephews mate has just acquired a car - dad and uncle are so called
mechanics, not too sure of what but as they don't have a timing light
between them I assume it must be diesel trucks or bus. Needs the carb
setting up, needs new plugs and leads. Nope ten seconds with a timing
light - it needs a new vacuum advance unit.

--
Peter Hill
Spamtrap reply domain as per NNTP-Posting-Host in header
Can of worms - what every fisherman wants.
Can of worms - what every PC owner gets!