98 Toyota Corolla Hard Start and No Power
I get a call to a shop that has an old Toyota that does not easily start and when started smokes and lacks power. The vehicle came to the shop as a no start. The plugs were soaked with fuel. The cylinders were blown out and the plugs replaced. Now the vehicle started. It smoked like over-fueling and lacked power. I was eventually able to get it warmed up and idling with some coaxing of the gas pedal.
When running the combined fuel trims were off about +15% total but not enough to cause this. The O2 sensors were cycling. When the fuel pedal was stabbed, the engine slowly accelerated. I could see nothing wrong with the electronic systems. The exhaust smoke had a smell unlike a rich exhaust but certainly looked like rich exhaust. The fuel tank showed about ½ a tank.
This is where sometimes we have to use our own senses to determine the issue. The vehicle showed the fuel system was adding fuel to maintain stoichiometry however there was visible smoke. The fuel did not want to fire but eventually did. The smoke did not smell like raw gas. It was more like Diesel or Kerosene. The driver of the vehicle was a new driver who was still learning. I called it as fuel contamination.
The shop owner also runs a gas station as part of his shop. He took a sample and sent to the chemists at the refinery. The analysis showed a large percentage of Diesel was mixed into the gasoline. The driver is not admitting what happened. Either they went to the fuel station and used the wrong pump or they were needing fuel and got it some other way? Well there you have it. Mystery solved.
Great diagnosis!, I have run into several vehicles with water in the gas or they put diesel in, two months ago had a 2013 Chevy Suburban that had a bag of sugar poured in by the owners ex wife! Had to replace fuel pump, flush all the lines , clean the tank, amazingly the injectors weren't ruined!
Hello, Steve Generally speaking, the gasoline must contain a little moisture to transport the sugar. I got into this many years ago with a high school teacher's car that had a cranking, no-start problem. Fuel pressure was to spec and, after removing the tank, I found the equivalent of a Big Gulp soda dumped into the fuel tank. Since the bottom of the tank was coated with dried caramel, the…
Would have been interesting to see what the specific gravity measured.
Hello, Greg. My experience is that relatively low percentages of diesel contamination are hard to detect. My own test is to rub a few drops of the suspect fuel between my fingers. If my fingers remain shiny after the fuel evaporates, I suspect diesel fuel contamination because diesel fuel won't evaporate. Others drop a small sample on the floor to observe how readily it ignites. Depending on…
Pretty interesting case, Michael Diesel fuel contamination is difficult to estimate because, unless we do a lab test, we don't know the percentage of contamination. Most recently, I experienced a number of cold starting problems with my own vehicles and a friend's 2004 5.3L Flex Fuel Tahoe as well. Our overnight temperatures have been dipping into the sub-zero range. The Tahoe's symptoms were…
Mike, you forgot to "scope all the things". - lol Bad gas ran me in circles once. Once. :-)
Nice job, Mike. Wrong fuel is a tough one to diagnose properly because you have seemingly everything you need to run. Your getting “fuel” you have spark and injector signal. Plus good compression. Usually at that point when you figured out you have everything, you have to start thinking which one is not the right one.