Two days ago the check engine light on my 2009 Grand Cherokee came on (14 months, 23,000 km, 80 octane gas). Not wanting to take it to the dealer, yesterday morning I added a bottle of Techron to the 2/3 tank of gas I had. This morning, after 24 hours and 110 km, the light is off. Problem solved.
The easy fix
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In many of the German makes, check engine light will come on if you don't tighten the gas cap properly. The light will then go away after a day or two. Is it possible the same thing happened to your Cherokee?
Techron is wonderful, it's solving a fuel sending unit problem now as we speak.
Am I reading it right that you put 80 octane gas in? US in minimum 87, and that low of octane, the motor may have detected engine knock from the knock sensor. Techron to the gas may have helped that.
Am I reading it right that you put 80 octane gas in? US in minimum 87, and that low of octane, the motor may have detected engine knock from the knock sensor. Techron to the gas may have helped that.
Could be a clogged fuel filter, at that mileage sounds right. Gas additive will open up enough passages so amount of restriction does not cause a problem. Filter will clog again. Gas additive will work each time, but time until next time it acts up will become shorter each time, because larger restrictions that do not dissolve will continue to build up. If it act up again in less than 6 months think gas filter, though you could also have other dirty parts in your fuel system. A gas additive once every 6 months is probably a good idea just to keep everything clean. But if you want to keep it running right and reliable, you probably should replace the fuel filter.
I vote the gas cap, at this low mileage there is nothing that would trigger a CEL from being dirty.
Originally Posted By: Quattro Pete
In many of the German makes, check engine light will come on if you don't tighten the gas cap properly. The light will then go away after a day or two. Is it possible the same thing happened to your Cherokee?
Nope, that is the first thing I checked, and of course put back on right after putting in the Techron. I've fixed a lot of problems with the stuff. I normally put it in at every oil change, but had forgotten. Have to wait til the tank is less than 12 gal, and my oil change light has gone off on the last leg of a trip the last 4 times, and I arrive with only about 3 gallons in the tank after the 300 mile stretch. Fill the tank, change the oil, clean off 300 lbs of mud.
As for Octane, the government makes the gasoline, determines the price, and delivers it that way to the gas stations that have to sell at the regulated price.
In many of the German makes, check engine light will come on if you don't tighten the gas cap properly. The light will then go away after a day or two. Is it possible the same thing happened to your Cherokee?
Nope, that is the first thing I checked, and of course put back on right after putting in the Techron. I've fixed a lot of problems with the stuff. I normally put it in at every oil change, but had forgotten. Have to wait til the tank is less than 12 gal, and my oil change light has gone off on the last leg of a trip the last 4 times, and I arrive with only about 3 gallons in the tank after the 300 mile stretch. Fill the tank, change the oil, clean off 300 lbs of mud.
As for Octane, the government makes the gasoline, determines the price, and delivers it that way to the gas stations that have to sell at the regulated price.
Gas in Bolivia probably has enough dirt in it to do in a fuel filter at 23,000 km.
Originally Posted By: mechjames
Am I reading it right that you put 80 octane gas in? US in minimum 87, and that low of octane, the motor may have detected engine knock from the knock sensor.
I was wondering this also.
Am I reading it right that you put 80 octane gas in? US in minimum 87, and that low of octane, the motor may have detected engine knock from the knock sensor.
I was wondering this also.
There are two choices here. 80 octane, or, sometimes, in about 3 gas stations in the 3 major cities, you can find 90 octane for almost double the price. Those three cities are along the central road that runs almost east/west.
That is why I run 28% av gas in the BMW, but that would kill the catalytic converter on the Cherokee. I had to pull the guts out of the converter of the BMW years ago.
That is why I run 28% av gas in the BMW, but that would kill the catalytic converter on the Cherokee. I had to pull the guts out of the converter of the BMW years ago.
Isn't most of Bolivia at generally high altitude? If so, high octane gas may not be necessary there.
Funny, I experienced the opposite
Added Chevron Techron Concentrate to 12 gallons of fuel (took the tank to below the E, pulled into the station, dumped the bottle in, then pumped 12.00 gallons of fuel). After about a 10 minute drive my CEL turned on.
If it were my gas cap, it would have turned on right away (at the pump) - but I checked the cap anyways, nope, still tight. Well, on the way to work that day, I took the vehicle WOT on the off ramp/merge lane, and the CEL went out.
My guess, it cleared something somewhere (o2 sensor, fuel sending unit, etc.....?) and the CEL went off.
If it were my gas cap, it would have turned on right away (at the pump) - but I checked the cap anyways, nope, still tight. Well, on the way to work that day, I took the vehicle WOT on the off ramp/merge lane, and the CEL went out.
My guess, it cleared something somewhere (o2 sensor, fuel sending unit, etc.....?) and the CEL went off.
The best difference I ever saw with Techron was a Villager minivan with 310,000 miles. A friend had bought it new, but it barely ran. She was putting premium gas, and had tried various things. The dealer wanted $3000 to fix it, so she bought a new car. She hadn't sold this when I was visiting the US for a few weeks, so she loaned it to me with a case of some additive.
It really did run bad, if at all. I went to Wal-mart and got two bottles of Techron, dumped them in when I filled the tank, and in a few days it was running great. When she picked it up after 3 weeks she couldn't believe how nice it ran.
I've also gotten my daughter's BMW and Subaru to pass failed Va. inspections with Techron treatments.
It really did run bad, if at all. I went to Wal-mart and got two bottles of Techron, dumped them in when I filled the tank, and in a few days it was running great. When she picked it up after 3 weeks she couldn't believe how nice it ran.
I've also gotten my daughter's BMW and Subaru to pass failed Va. inspections with Techron treatments.
Originally Posted By: severach
So you got a little improvement and quit? If you'd have run low dose Techron for a whole year your friend might have regret her decision to buy a new car.
She kept the van until her son got his license and gave it to him. Still running today. Something like 5 years later, maybe 6.
Although she has since traded in the Lexus she bought that time.
So you got a little improvement and quit? If you'd have run low dose Techron for a whole year your friend might have regret her decision to buy a new car.
She kept the van until her son got his license and gave it to him. Still running today. Something like 5 years later, maybe 6.
Although she has since traded in the Lexus she bought that time.
Originally Posted By: OtisBlkR1
Advanced auto is running Chevron techron on special right now, buy one get one free $7.99 12oz bottle. I loaded up on em
I was there and picked up a couple as well. I'm thinking of going back and getting more.
Advanced auto is running Chevron techron on special right now, buy one get one free $7.99 12oz bottle. I loaded up on em
I was there and picked up a couple as well. I'm thinking of going back and getting more.
But but but... MMO is only 12 bucks a gallon, rite???
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