Aspire getting only 22mpg!!

[gtd2000]

Does your cars have EGR? Clean it or block it off and see what she does.

Where should we look for that?

[yvanlavoie20]

axygene sensor test

a volt meter on the black wire and ground, you must see 0-.2 to .75-1 volt switching low to high when running at steady speed ( 60 mph for example ) if it don't go under .3 volt you are running too rich, if it wrong go over .75 volt your sensor is bad or fuel pressure is low. if it go negative replace it!

[ericsmith32]

On the carb'd I can't remember exactly. Look for a saucer shape object with a hose attached the top and the bottom to the intake manifold, has a wire or two coming out of it. I looked at your pics and I didn't see one so either you don't have one or it's hidden.

[gtd2000]

This car is FI...but I'll take a few snaps of the throttle body etc and any diaphragm/saucer shaped contraptions

[FestYboy]

Does your cars have EGR? Clean it or block it off and see what she does.

I'll have to get back to you on that one but that's a remote possibility as the engine idles fine and the puter isn't seeing any voltage at the EGR sensor when at idle or normal driving (i have an OBD II scanner). and the fuel filter is 4000 mi new. injector pulse width is normal and MAF sig is good.

a volt meter on the black wire and ground, you must see 0-.2 to .75-1 volt switching low to high when running at steady speed ( 60 mph for example ) if it don't go under .3 volt you are running too rich, if it wrong go over .75 volt your sensor is bad or fuel pressure is low. if it go negative replace it!

Yvan, remember that you have to use an analog meter or oscilloscope to test O2 sensors properly. a digital meter can't react fast enough to give you a good picture of what the O2 sensor is putting out. normally a sensor (for fords) will switch about 6-8 times per second and you can test it while at idle (preferred). the stock ECU can react to a range from .2-.8V without putting on the SES light. the main thing is it has to see a switching from high to low within a certain amount of time or it'll throw a code and turn on the SES light.

hope that clears up some things

Arty

[yvanlavoie20]

lol

sensor on aspire - festy are one wire = slow ones...even with a slow tester you can see volt change...i never see one switching at that speed in 13 years of ford master tech...in real worlds even wide band used in newer model switch about 3 to 4 time per second at driving speed, no analog meter can move so fast...even a simpson professional one.
i test a 10 $ meter and a 750$ ( mine ) , both read about the same.except if you put the cheap one on the spark plug wires 8) it is not protected from high voltage induction...on aspire and festy, many sensors wont go over .1 volt when idling, the sensor is too cold to generate voltage.. try your test at 60 mph and see :lol:

[FB71]

woah! NEVER use an analog volt meter on an O2 sensor! It doesn't have enough impedance. My Simpson 260 only has like 10k resistance, way too much load for the zirconium cell in an O2 sensor. Less than 2 or 3 Meg will burn out the cell. You need a graphing DVOM (10Meg impedance) or a scope (20-50Meg impedance).

[Tim]

Didn't know that...

Glad you said something before I hooked my 260 (best $20 I ever spent) up to the sensor to see what it was doing... :shock:

[FB71]

the stock ECU can react to a range from .2-.8V without putting on the SES light. the main thing is it has to see a switching from high to low within a certain amount of time or it'll throw a code and turn on the SES light.

hope that clears up some things

Arty

hahaha, SES lamp. We can tell someone got brainwashed by GM early on....

us FORD guys (and gals) call it a MIL (Malfunction Indicator Lamp)

just fun little facts....

and Tim, I got my 260 for free! Amazing what people put little to no value on!

[gtd2000]

So how is it I go from 26 to 40mpg again?...... :lol:

[packrat427]

Man I am happy for you ,I thought you were never going to get your millage back .

[gtd2000]

Man I am happy for you ,I thought you were never going to get your millage back .

Unfortunately I'm just kidding....

Same old MPG here

[yvanlavoie20]

sensor

lol...even with 12 volt on the black wire, even shorted you cant burn the sensor because it is a voltage generator...lol and yes an old Simpson do a great job for checking the voltage on this type of sensor but needle are too slow to catch peak volts...