O2 sensor location F53 chassis, 1996 Ford 460?

93Cobra2771 wrote:
Excellent, hope that does it for you.

You still need to disconnect the battery for 30min to clear your short and log term fuel trims. Hopefully your fixed vacuum line does the truck.

Thanks, I'll definitely do that.

Excellent, hope that does it for you.

You still need to disconnect the battery for 30min to clear your short and log term fuel trims. Hopefully your fixed vacuum line does the truck.

Cobra, it seems your number 2 suggestion was spot on. Found a vacuum leak. Looks like mice chewed off the end of a capped port. Heading into town to get a new cap now. I hope every fix is this easy (knock wood).

Thanks for all your help!

Other thoughts:
Leaky injector
Bad Fuel pressure regulator (rail pressure check would determine that)
TPS sensor

There are tests for all of the above situations, and specific test to determine if certain sensors are within spec.

If the CEL is popping and then going away relatively quickly, then chances are a sensor is on the verge of being bad but is "on the threshold" of being bad.

As I said above, we are flying blind until we can hopefully start with the code it is popping. Worse comes to worse, have your scanner with you and plug it in as soon as you see the code.

lawdash wrote:
Thanks Cobra, that does help. I have sporadic check engine light but the computer won't give up the code. Also getting some nice backfires and lots of sputtering. Climbing into higher elevations makes it worse. I think O2 sensor seems like the most likely culprit, would you agree?

When you say it won't give up the code, what do you mean? Do you mean unless the light is actually lit you can't pull the code? Or do you mean that you scan the code and it won't give a code number?



Is the chassis OBDI or OBDII? If it only has one O2, and no cat, then probably OBDI.

I'm not very familiar with Ford MH chassis, but I am intimately familiar with Ford Fuel Injection Controls in general.

An O2 sensor on the way out will not typically cause the symptoms you are describing. When O2's start going, the heated circuit is what usually goes first. This means that the O2 isn't preheated so it can start "switching" correctly. The other way an O2 will go bad is they stop "switching" due to age or contamination. When that happens, the vehicle will run off calculated tables.

Sounds more like an issue with:
1. Bad MAF unit (assuming it has one). Does your chassis have a Mass Air Flow? I'm guessing not. I'm thinking Ford never had a 460/MAF combo but my memory is a bit fuzzy on that.
2. Vacuum leak of some type. Is the backfiring occurring in the exhaust or in the intake?
3. Exhaust leak - believe it or not, an exhaust leak can give issues on fuel injected motors like you describe.
4. EGR valve stuck open - this is basically a giant vacuum leak.

Honestly, it's going to be a lot of guesswork until we can get a code pulled. You can throw parts at it, but it's like gambling. However, I will say that if it has the OEM/original O2 sensor(s) on it it, they are far past time for a change. I think the life expectancy on O2's degrades significantly after five years.

By the way, any time you install any new sensor on your vehicle, disconnect the battery for 30 minutes (in fact, disconnect the battery before you do any work on your car is good practice). The disconnect will clear all short and long term fuel trims and let the EEC relearn it's adaptive strategy.

In fact, before you replace ANY parts, lets try a little test: Disconnect your battery for 30 min and take it for a drive and report if it acts any better or not.

lawdash wrote:

RLS7201 wrote:
The O2 sensor (only one) on you chassis is located at the end of the "Y" pipe, just in front of the resonator. It is mounted on top of the pipe. No catalytic converter on 1994-1997 Ford F53 chassis.

Richard

Thanks Richard! Do you know what part # I need? Sometimes car parts places get confused when I tell them Ford 460 on F53 chassis.

Look up the part on http://www.rockauto.com/ and then take that number to your local parts store. Or purchase from Rockauto. What ever you like. I suggest you spend the extra money and buy a Bosch O2 sensor.

Richard

RLS7201 wrote:
The O2 sensor (only one) on you chassis is located at the end of the "Y" pipe, just in front of the resonator. It is mounted on top of the pipe. No catalytic converter on 1994-1997 Ford F53 chassis.

Richard

Thanks Richard! Do you know what part # I need? Sometimes car parts places get confused when I tell them Ford 460 on F53 chassis.

The O2 sensor (only one) on you chassis is located at the end of the "Y" pipe, just in front of the resonator. It is mounted on top of the pipe. No catalytic converter on 1994-1997 Ford F53 chassis.

Before you spend any money, put a pressure gauge on the fuel rail. Aprox. 38# of pressure at idle and 42-44# at full throttle. Pressure regulator is vacuum controlled. The sputtering may be from lack of fuel. Older F53s are notorious for failing fuel pumps.


Richard

Thanks Cobra, that does help. I have sporadic check engine light but the computer won't give up the code. Also getting some nice backfires and lots of sputtering. Climbing into higher elevations makes it worse. I think O2 sensor seems like the most likely culprit, would you agree?

If you have an O2 sensor going, you should have a check engine light lit. FYI, there may be more than one O2 sensor on your chassis.

Usually, there is an O2 sensor for each side of the engine (would be located somewhere between the exhaust manifold and the point where the exhaust y's together into one pipe). Generally closer to the manifold side.

There may also be a rear O2 sensor that is plumbed into the single pipe located downstream of the catalytic converter(s) - assuming that it has cats that is.

Your check engine code will tell you left bank, right bank, or rear O2 sensor as far as which one isn't working. I will say that if you are going to replace one bank, go ahead and replace the other bank as well so that you have fresh ones on both sides.

R&R is straightforward. Put a wrench on it and remove. HOWEVER, they are often seized into the exhaust pipe, so liberal shots of a penetrating oil daily for a week or so prior to removal is a great idea. Sometimes, they are located in such a way that a special O2 socket has to be used for removal. They are available at any parts store.

Hope this helps.