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This is a 1997 FJ80 with 191k and maintenance being up to date, with no known issues with the engine or transmission. This was really weird. I went on a pretty long and rough fire trail for about 5 miles, nothing that was too extreme. I’ve probably averaged around 10mph. It was raining/light snow and outside temperature was around 45 degrees F. I’ve kept my eyes close to the ScanGauge for engine temp and my Bosch transmission pan fluid temp gauge. Both were within normal conditions but the transmission was colder then usual, probably due to the weather. Last 10 minutes of the drive I’ve got on a paved road which lead to the main road, and it was snowy. The snow was extremely tacky, it was sticking to anything and my car was starting to get covered up with ice.
That road was pretty steel uphill garage at about 5k altitude. The wind was heading towards me as well. This is where the problems started, I couldn’t get the car above 35mph with foot all the way down. I assumed it was due to the conditions I was driving thru and the steel slope.
After turning on the main road, I started to go downhill but I’ve noticed my car was hesitating. It did not want to get above 1500rpm and was severely bogging down. If I was to accelerate it would get to couple hundred rpm and that start to bog down to a crawl. Only way I could get momentum is to floor it after which I would kick in high gear and accelerate until it switches to the lower gear and start to bog down. It would do this in L,2nd,D and R gears. Since the first symptom, I’ve checked my transmission fluid [which was full but cold], and I’ve had my eyes on the trans gauge which was now reading below 100F. I could rev the engine up in neutral no problem. I’ve stopped and tried to put the car in park it didn’t want to go until I made multiple attempts [i suspect the reason is due to being packed with snow/ice]. I’ve hopped out to inspect for physical damage [none that I could find], and check fluid [full]. The fluid was cold to the touch. I’ve noticed the underbody of my truck was stuffed with snow, literally snow and ice blocks everywhere, on top and under transmission, on the side, in the axle springs, packed on top of axles, everywhere.
The only thing I could think of is that the transmission was literally too cold? Ive sat for 15min to try and let the truck warm up (it’s still very cold and raining/snowing) outside, but it did not fix the problem. After limping it to the closest parking lot (primarily downhill, which it could speed up past 30mph), the issues remained and I had to keep flooring it periodically for it to kick into a different gear and accelerate before it would bog down. Once we reached the parking lot the snow was still there but slowly melting, all the fluids were still ok and I didn’t see any physical damage. After letting the car warm up for 30min the symptoms didn’t appear to improve at first. I was able to get it home by flooring it to get up to 50mph and then I was able to coast home. After the drive ( 2 hours), my transmission seem to act better but it 100%.
Here are my theories,
1) burned a gear up by going up the slope too long and potentially by being in the same gear thru the fire trail
2) fluid not able to circulate due to freezing?
3) some king of mechanical damage inside which seem to cure itself after?
This was the weirdest thing I’ve ever experienced, if anyone has any input please let me know. Thanks
[QUOTE]Solution- I found a thread that which had a similar power loss issue. They had water in the O2 connectors. I took them apart and they still had moisture in them after a couple of days. After taking out the inserts , I blasted them with electronics cleaner and loaded them up with a dielectric grease. This has seemed to fix the problem for now.[/QUOTE]
If you have a loss of power problem, such as the truck bogs down and misfires only under medium throttle and under load, but goes fine if you floor it, and doesn’t have the symptoms in neutral, check for moisture in the O2 sensors as well as their resistance values. Replacing my O2 sensors with lower resistance values has fixed the issue so far.
This is a 1997 FJ80 with 191k and maintenance being up to date, with no known issues with the engine or transmission. This was really weird. I went on a pretty long and rough fire trail for about 5 miles, nothing that was too extreme. I’ve probably averaged around 10mph. It was raining/light snow and outside temperature was around 45 degrees F. I’ve kept my eyes close to the ScanGauge for engine temp and my Bosch transmission pan fluid temp gauge. Both were within normal conditions but the transmission was colder then usual, probably due to the weather. Last 10 minutes of the drive I’ve got on a paved road which lead to the main road, and it was snowy. The snow was extremely tacky, it was sticking to anything and my car was starting to get covered up with ice.
That road was pretty steel uphill garage at about 5k altitude. The wind was heading towards me as well. This is where the problems started, I couldn’t get the car above 35mph with foot all the way down. I assumed it was due to the conditions I was driving thru and the steel slope.
After turning on the main road, I started to go downhill but I’ve noticed my car was hesitating. It did not want to get above 1500rpm and was severely bogging down. If I was to accelerate it would get to couple hundred rpm and that start to bog down to a crawl. Only way I could get momentum is to floor it after which I would kick in high gear and accelerate until it switches to the lower gear and start to bog down. It would do this in L,2nd,D and R gears. Since the first symptom, I’ve checked my transmission fluid [which was full but cold], and I’ve had my eyes on the trans gauge which was now reading below 100F. I could rev the engine up in neutral no problem. I’ve stopped and tried to put the car in park it didn’t want to go until I made multiple attempts [i suspect the reason is due to being packed with snow/ice]. I’ve hopped out to inspect for physical damage [none that I could find], and check fluid [full]. The fluid was cold to the touch. I’ve noticed the underbody of my truck was stuffed with snow, literally snow and ice blocks everywhere, on top and under transmission, on the side, in the axle springs, packed on top of axles, everywhere.
The only thing I could think of is that the transmission was literally too cold? Ive sat for 15min to try and let the truck warm up (it’s still very cold and raining/snowing) outside, but it did not fix the problem. After limping it to the closest parking lot (primarily downhill, which it could speed up past 30mph), the issues remained and I had to keep flooring it periodically for it to kick into a different gear and accelerate before it would bog down. Once we reached the parking lot the snow was still there but slowly melting, all the fluids were still ok and I didn’t see any physical damage. After letting the car warm up for 30min the symptoms didn’t appear to improve at first. I was able to get it home by flooring it to get up to 50mph and then I was able to coast home. After the drive ( 2 hours), my transmission seem to act better but it 100%.
Here are my theories,
1) burned a gear up by going up the slope too long and potentially by being in the same gear thru the fire trail
2) fluid not able to circulate due to freezing?
3) some king of mechanical damage inside which seem to cure itself after?
This was the weirdest thing I’ve ever experienced, if anyone has any input please let me know. Thanks
[QUOTE]Solution- I found a thread that which had a similar power loss issue. They had water in the O2 connectors. I took them apart and they still had moisture in them after a couple of days. After taking out the inserts , I blasted them with electronics cleaner and loaded them up with a dielectric grease. This has seemed to fix the problem for now.[/QUOTE]
.
If you have a loss of power problem, such as the truck bogs down and misfires only under medium throttle and under load, but goes fine if you floor it, and doesn’t have the symptoms in neutral, check for moisture in the O2 sensors as well as their resistance values. Replacing my O2 sensors with lower resistance values has fixed the issue so far.
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