going in the garage for the winter

[lastexit99]

gotta ask you guys for some advice...

I am about to put my 96 Cobra in the garage for the winter, and I gotta figure what to do about the gas mileage problem. I am currently seeing about 11 - 13 MPG which is about half of what I used to get. The only code i can find is the P1443 code which should not be giving me as much of a drop in mileage as I am getting.

Other than that code though I am not getting a "gas smell", I changed the air filter, fuel filter, replaced the air intake hose where it was leaking, I don't want to just put random parts on it hoping to figure out what is wrong, but I can't really afford to drive as my fair weather DD getting that crappy a gas mileage.

what do you guys recommend?

 

[Bright Blue Cob]

I had that code for a while before I discovered it was only the vacuum line going to the throttle body had collapsed from age and heat and there was no noticeable degradation in fuel economy, just a nasty gas smell when filling it up. Have you checked your spark plugs for condition? A leaking injector should show up on your plug as black and possibly smelling like fuel. Does it drive normally with the same get up and go etc?I would also check the fuel pressure regulator.

 

[deadernie]

Are you getting a raw gas smell like possibly a leak or a unburned fuel/ running rich smell?

 

[lastexit99]

One thing I did this summer was replace all my Spark plugs & plug wires, so i'd like to think the problem isn't with them. I did inspect the old ones as they came out, and didn't see anything out of the ordinary with them.

No gas smell either.

I was thinking the O2 sensors were probably bad, but the Ford dealer said that would have shown up when the codes were pulled and it didn't. I guess I should track down the source of that code.

 

[Tabres]

I wonder if your fuel filler neck grommet is perished and you're losing fuel out of there...

 

[Noreast]

I wonder if your fuel filler neck grommet is perished and you're losing fuel out of there...

+1 happened to a lot of us

 

[lastexit99]

what would be some tell tale signs of this happening, so I can check it out?

 

[SVTContique]

what would be some tell tale signs of this happening, so I can check it out?

Moist looking around the filler neck-to tank grommet.

I replaced mine this year, its not that bad to do.

 

[SVT Rob]

I wonder if your fuel filler neck grommet is perished and you're losing fuel out of there...

+1

+1 happened to a lot of us

Just replaced mine a few weeks ago

Moist looking around the filler neck-to tank grommet.

I replaced mine this year, its not that bad to do.

Took about 30 minutes, didn't have to drop the tank at all.

I replaced that, and did the plugs, and my fuel economy went back up from 14-15mpg in town to 17-18mpg in town.

 

[racecougar]

I was thinking the O2 sensors were probably bad, but the Ford dealer said that would have shown up when the codes were pulled and it didn't. I guess I should track down the source of that code.

O2 sensors get lazy long before they reach the point of throwing a CEL. If they have 80K miles or more on them, it certainly wouldn't hurt to change the primary O2's out with a new pair.

 

[lastexit99]

well, my o2 sensors are the ones that the car came with, and have 111,000 miles on them. So maybe it wouldn't hurt to change them anyway. I guess it can't make things worse.

 

[SVT Rob]

Hmm ... I've got 152k on my original O2's, that might be something I'll change out in the next couple weeks.

 

[racecougar]

The NTK upstream sensors are ~$60 for the pair on rockauto. I would definitely expect to see an improvement in mileage if you replace your original O2's with them.

 

[lastexit99]

ok so after waiting for the rain to stop and driving the car today, I crawled under it to check out the fuel grommet. I appears as if that may be at least part of my issue. There is "not quite dry" "road dirt" caked around it that has a slight gas smell to it. So I am goign to replace it.

I am also going to replace the oxygen sensors, since they are at least adding to my problem and it won't hurt. Just for my own protection, and since I've never replaced them before, the guy at advance said the "Bosch" brand are all the same part number and I need 4 of them. Does that sound right? I was thinking from things I've read that the upstream pair should be different from the downstream pair.

 

[racecougar]

I am also going to replace the oxygen sensors, since they are at least adding to my problem and it won't hurt. Just for my own protection, and since I've never replaced them before, the guy at advance said the "Bosch" brand are all the same part number and I need 4 of them. Does that sound right? I was thinking from things I've read that the upstream pair should be different from the downstream pair.

The Bosch O2's use the same part number for both upstream and downstream sensors, however most manufacturers do not follow that practice. I'd recommend using either NTK or Motorcraft O2's. You'll also save a good deal of $$ by ordering them online (i.e. Rockauto), than you will by buying them at your local auto parts store.

I would only replace the upstream sensors, as they are the ones that effect AFR. The downstream sensors just measure catalyst function.

 

[lastexit99]

thanks for the advice, I took your advice, and ordered the motorcraft upstream sensors. I offically have my fingers crossed that these things fix my problem.

 

[lastexit99]

a little update...

Last night I got my new oxygen sensors installed. I only have gotten to drive it for a little bit. What I for sure have noticed is the car runs alot smoother. By smoother I mean as the tac runs up the car just pulls better and on a more even pace. Of course this is anecdotal, but it seems to have more power also. Of course the real question is that only time will tell about the gas mileage. It is due for a tank of gas now, so I will hoepfully know something in the next day or two.

I did get the tank grommet also, but I didn't install it yet, because I wanna see if the o2 sensors fix the problem.

So I guess what I am saying is, "wish me luck".

 

[lastexit99]

one more thing, I just filled up the tank, did my calculations, and my last tank was 12.2mpg. I'm looking for around 16 - 17 mpg. Assuming I stay in town, if I get out on the interstate I'm hoping for aoruns 20 - 22.

 

[lastexit99]

update...

After changing the o2 sensors and filling the tank up I am not-so-pleased to report that the gas guage is showing 1/2 full and the trip meter is at 93 miles. So it seems that the sensors had little to no effect on the gas mileage. They did however seem to make the car run better and smoother.

I guess this weekend I am goign to look in the passenger side inner fender and see what state that evap cannister is in and replace all the vacuum lines there. Hopefully I will get the gas tank grommet replaced too.

After that I'm not sure what to do to fix this problem?

 

[racecougar]

update...

After changing the o2 sensors and filling the tank up I am not-so-pleased to report that the gas guage is showing 1/2 full and the trip meter is at 93 miles. So it seems that the sensors had little to no effect on the gas mileage. They did however seem to make the car run better and smoother.

I guess this weekend I am goign to look in the passenger side inner fender and see what state that evap cannister is in and replace all the vacuum lines there. Hopefully I will get the gas tank grommet replaced too.

After that I'm not sure what to do to fix this problem?

You can't expect to get accurate mileage info based on the fuel gauge, and certainly not on just one tankful.

If you're leaking fuel from the grommet, that would certainly hurt mileage.