I have 2003 Dodge Caravan SE, which takes E85 (has the E85 sticker on the
gas cap door), but I've never used it before. The other day my tank was half
full, and I filled it up with E85. A couple dozen miles later my check
engine light went on. It stayed on for a couple of days. Today the check
engine light didn't go on; but it's also much colder today than it's been
the past couple of days, so I don't know if that has anything to do with it.
So I was wondering if anyone has heard of any problems using E85, such as
might cause the check engine light to come on, or otherwise. (The car
actually seems to ride a little smoother; but that could just be my
imagination.) I need to get my state inspection sticker next month, and I
certainly don't want any problems with the check engine light right when I
have to do my inspection.
I can also help:
Most likely the fuel sensor in the fuel line. But that's just a guess. The
computer sends a richer mix on E-85, because Ethanol does not have the BTU's
nor the flame propagation of gasoline.
I know the owner's manual says that the check engine light might come on
when you use cheaper gasoline. So that might be the same thing. However, the
check engine light's going to come on whenever I use E85, then the car's not
really made for using E85, is it?
I wonder if the alochol in the E85 cleaned something (like a sensor) and
the change triggered the light. Then as things... settled down the
light went off.
In any case no doubt you noticed a significant drop in your gas mileage...
Here's an interesting thing re. this. I didn't get the fault code yet
because, as noted, the check engine light was off.
The last time I had put half a tank of E85 in, so it was 50% E85. Tonight I
got gas again, and filled up with E85. The tank was 1/3 full, so it now is
about 85% E85.
Though, as noted, the check engine light has been off, about 5 miles after
filling up again on E85, the check engine light went on again.
So that's twice in a row that it went on after filling up on E85.
I think I found the solution to this. There's an article at
which says in part:
"Dee Rithman, the owner of a 2000 Ford Taurus, was happy to learn that her
car was designed to accept E85 even though there are currently no ethanol
filling stations in her area. On a recent trip to Austin, she came by an E85
station and decided fill up with the gas alternative. 'About three or four
days later, I'm getting the check engine light on my car,' she says. For
$70, a mechanic told her 'because you've been putting regular gas in it for
six years, the engine's not going to take it because it's not used to it.'
"WOAI contacted the National Ethanol Vehicle Coalition who said that,
unfortunately, a lot of drivers experience this, but the problem is neither
serious nor permanent. They said that the check engine light should turn off
after the first few E85 fill-ups. They also suggest that you may be able to
avoid the problem altogether by slowly introducing ethanol to your engine a
few gallons at a time."
The engine wasn't used to it?
Sounds like a Ford problem, but mechanical things don't get used to things.
Newer vehicles have a sensor that actually determines the ethanol content.
But, the few tanks of E-85 usually cleans off the sensor.
So you're saying that the sensor isn't working right until the first few
tankfuls? And then, once it gets cleaned off, it works properly?
I wonder about my situation where the light went on when I was using 50%
E85, then turned itself off after a couple of days, and then went back on
right after I increased the E85 in the tank to 85%.
That's true, and good point. I guess it was the article, combined with the
fact that the light went off by itself (and then only went on again when I
increased the concentration of E85) that makes me feel comfortable about it.
But, I need to get my state inspection this month, and am hoping the light
goes off before that. So, whether the light goes off or stays on, I'll have
to bring it in and I'll get the code read. Or would I need to bring it to
the dealer to get the code read?
If there is a fault code , it may have disabled an IM monitor. The vehicle
will not pass if all monitors have not been run. That's why I say to have
the fault code checked and make sure the problem is fixed. Some monitors
could take days to run and pass
Said the same thing said me a while ago. Just because the lite went
out, doen't mean the fault code isn't there. Instead of relying on
an article and thinking you know, get the fault code read and then
know for sure.
Ethanol has more water than anything else:
There's always garbage on the bottom of the tank, so increasing the alcohol
content, tends to loosen up the water soluble; i.e.: Rust, sand, metal
filings that haven't stratified to the bottom of the tank yet.
So, usually the sensor will clean it self, with the fuel flow. But, on the
other hand. Sometimes the garbage solidifies on the sensor, or renders it's
ability to measure the conductance of either fuel in the mix, and can be
removed and with a little luck, cleaned off.
Otherwise, you'll need a new one. I helped a friend at a dealer diagnose
one, and the sensor was about $87.00 plus tax.
I hope this helps.
I think in your case, the sensor might be covered under the federal
emissions warranty, which I believe is 7/70 or 8/80.
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