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Mexican Fuel Issues?

After two and a half years living in Mexico (quite nice, thanks for asking), our 2000 Toyota 4Runner with 170,000 miles is running a bit rough. We have had a hard time getting a computer diagnostic (check engine light comes and goes, almost always on last quarter tank of gas) because Toyota didn’t get established here until2004 and the dealers won’t work on a Toyota that is older than 2004. We replaced the fuel filter, but the vehicle has a tendancy to stall when accelerating from a stop. It seems to run smoothly once we are up to speed. The Pemex gas has a bad reputation for no detergents and possible water content. Do I need an injector cleaning? Could I have a sensor wearing out? Hard to diagnose without a computer analysis?



Can you get some techron additive? A double dose might help.

Under the circumstances, I’d agree with trying the techron.

If you were to order a code reader and a maintenance manual over the internet, do you think you’d be up to reading the codes?

Does it still have the origina; sparkplugs and air filter in it?

Where in Mexico? If the Cel comes on, even intermittently, codes will be left in the computer and most repair shops can read and deal with them…

You can get a CAN OBD II code reader from Ebay for as little as 25 bucks. With the ignition OFF, plug it into the connector that is located at the bottom of your dashboard on the driver side or refer to your owner’s manual. Get the code and post it here or search the internet for advanced interpretation beyond the simple and brief interpretations that come with the code reader. Disconnect the code reader with the ignition OFF! I’ve had mine for a few years; can hardly wait to need it. Not!

I cannot speak to gasoline quality in Mexico. My car has been here for most of the last 5 or 6 years, and I have had no fuel problems at all, at least as far as I know.

Some of the Mexicans claim Premium is better than Magna, but since I haven’t tried Magna I cannot say.

Oops! just did a bunch of Googling, and found a forum which said some Magna comes in from the US with little additives, but 100% of Premium is imported with additives. So, my suggestion is start using Premium. The Mexicans who told me this may be correct.

Pemex has just completed renovating their stations, most of the ones open today are less than 5 years old with new fiberglass tanks and pumping equipment… Mexico exports petroleum products to the U.S. They import very little. Magna (Regular Unleaded, 87 octane) is a dyed a light pink color, Premium, 92 octane, is a light green color…Pemex gasoline’s do not contain any ethanol. They DO contain an additive package that satisfies new car warranty requirements. My fuel injected Crown Vic and Dodge trucks run FINE on the 87 octane Magna. 11 Pesos/Liter. That’s about $3.50-$3.75 a gallon…

Thanks for the advice. The techron is coming tomorrow. Will give that a shot.

If I were you…I would install a separate and external “sight glass” so that you can see your fuel. Clean Fuel is an EXTREMELY important variable in making your engine run properly. Clean fuel is also something that ALL of us take for granted…I mean how many of us suspect our fuel that we recently pumped into the tank as being a reason for engine running issues? I can tell you the answer is “Not Many” We take this for granted ALL THE TIME…If you have reason to suspect the fuel that you are buying…you need a “Sight Glass” to see if you are getting water contamination in your fuel…It will save you from tearing out your hair in large clumps while you try to diagnose all sorts of engine issues that MAY be caused by inferior fuel quality. Fuel quality is paramount and always taken for granted…SO you need to add an external sight device to help you deal with this issue.

If you dont want to alter your fuel system…you can just bring a glass pickle jar with you when you go to fill up… fill the pickle jar with a few inches of fuel…and see if you get any water separation…If so…No Go…

NOTHING we say as far as diagnostics will help if the fuel quality is suspect…bec none of us will know whats in your tank…and everything depends on it…aside from your radio and electrical system… LOL