Hello! I know, it's a little strange to write here because I'm from Russia, and no one probably heard about my car model, but anyway... It's a 2008 Lada (VAZ) Samara 2114, four cylinder, eight valves.
So, I was running 95-octane gas and was pretty happy with it. The car was rated to run on such gas, so everything went fine. Beforehand I had an intercooler replaced, because it started leaking. With a new intercooler, my car was still getting pretty hot, especially with 95 gas. It was very apparent when idling at stop lights - the fans were engaging and it was very noisy.
My point is, on 92 gas it was better. Well, at least in terms of temperature... But when I went back to 92 to remove the overheating problem, my car lost torque. It was especially apparent when trying to start from a stand-still. Pressing the throttle all the way and not getting the power made me nervous, and yeah...
I went to a gas station and bought some high octane gas. Not 95, not 98, but 100 gas. The highest you can get in Russia. And then true problems began...
After starting the engine next day I noticed huge misfiring problems. The engine was vibrating like crazy, stalling while idling. But I still had to drive, so that's what I did.
I was driving 80-90 km/h on a highway for 10 minutes, and after stopping at a stop light, i noticed steam coming from my engine. The coolant was fine, 92 degress Celcius. But the engine sure did overheat. I went to a parking lot to investigate, and sure thing, there was a lot of steam, and some cylinders turned off due to multiple misfires happening.
So, I guess, high octane gas does damage to lower octane rated cars? I have already filled my car with 95 gas, but there is still some 100 gas in the tank. The engine also started making squeaking noise after that highway ride. The noise is almost like when a generator belt gets wet and misses the gears, but not as loud and very constant.
Can I do something to fix the overheating? Does the noise go away over time as the engine cools down and stops getting 100 fuel? I'm really worried. My car already has 220000 km of mileage (kilometrage, sorry!) and the engine was damaged by extreme overheating once (when the radiator leaked, all my coolant went away and my engine was running with no coolant for 15 minutes of high speed driving on the highway). It had the same squeaking noise after running like that, but in the end it stabilized, the noise went away and happy end! Don't know about this time, though...
Thanks in advance, Aleksandr from Podolsk, Russia!
I've never heard of that happening on cars sold in the U.S., the general consensus here is using high-octane gas for a car not designed for it is a waste of money but won't hurt anything. I've heard of the Samara but have never seen one (not imported here, maybe Canada?) and sure as heck never worked on one! I would probably start looking for cooling system or head gasket problems.
No Ladas in Canada
I'd heard they used to be sold there, they got some Eastern Bloc cars there. Back in the early 80s on a visit to Canada I stopped into a Skoda dealer out of curiosity, this is when they were still rear-engine. Still have the brochures around somewhere.
https://www.autoweek.com/car-life/classic-cars/a1844686/8-imports-canada-got-america-did-not/
well none of them lasted 😆 I've seen one or two.
Geez, I wonder why? 😆
Hello fellow Russian! 🙂
I'm not sure that this problem could be caused by a high-octane gas. If anything, higher octane reduces the risk of premature detonation and generally has a lower burning temperature (or so I heard), reducing the risk of blowing your engine's head off.
Most likely it's been caused by some problem in your cooling system. Also, since you have squeaking noises, check if your engine gets enough lubrication (i.e. you're not low on oil and use the proper viscosity).
To all Americans wondering about weird octane nubmers the OP is referring to: unlike AKI in the US, we use Research Octane Number (RON) to measure gasoline octane number in Russia. Common gas types available here are 92, 95, 98 and sometimes 100 RON (83-87, 90-91, 93-94 and 94-100 AKI accordingly), with 92 and 95 RON being the most popular. Lada engines are still largely based on the old USSR-era designs and were originally supposed to run on lower octane gas, so people are wary of using higher-octane fuel in these.
Thanks for the answers, guys!
I think, my engine is living its last days. I've opened the hood today to check the oil level, it was fine. But I've noticed some weird redish substance on my spark plugs. Even without unscrewing them, which is very strange. Like, the nuts of the spark plugs got that substance. Today I have driven the car again, and noticed that it became more stable on operating temperature, no more stalling while idling. And the idling was stable-ish. Without big deviations in rpm's. But, the car lost even a little bit more power and torque. Misfires are still happening. I really don't know, what to expect next. Is it a good idea to check my spark plugs and replace them?
Red-ish substance on the upper part of the spark plug (the one that is not inside the combustion chamber) could be a mix of oil leaking through and a corona discharge caused by bad electrical insulation on the ignition coils. BUT if you have red residue on the spark plugs's electrode side — this is a sign of one of the lowest-quality octane boosting additives there is (I forgot the exact name of it, sorry). If you still have some leftover fuel from that gas station and a cash receipt — feel free to sue them (yes, you can sue bad gas stations in Russia if you can prove that they sold you this fuel).
Out of curiosity, where did you buy this 100 octane gas? Was it one of the bigger players' stations (like Rosneft, Gazprom or Lukoil) or some smaller company? I usually buy 95 octane fuel at Rosneft and it's been pretty good so far.
In any case, I'd recommend you to check and/or replace the spark plugs and also check the ground (or "mass" as they call it on Russian car forums) connectivity — I had a similar idling problem recently and it was caused by dirty and corroded connections. I'd also take a sample of that 100-octane fuel and have it checked, just in case.
The red substance might be dielectric grease.
the problems might be stemming from the overheating event you had. Did you have the heads machined and rebuilt?
