So I'm passing a car at WOT in Drive, as It is getting to upshift to 3rd it cuts out on me, let up a bit on throttle and surges back strongly. I repeated the next time I passed a car and it did the same. Should I point my finger at the rev limiter ? Or could it be because I am manually downshifting to drive before I accelerate and pass at WOT ? Any help is appreciated.
Not sure but It seems to hesitate from stop & start now. Going to throw my spare tach on it to see what I'm getting for RPM's at cut out point. What is "stock" rev limit?
I don't know if the cutoff is 6,500 or not, but when I hit mine I knew it, there was no confusing the rev limiter, to the engine cutting off.
With my 9C1 I didn't realize I had dropped her down to first, and not second gear. When I was hitting the cutoff the engine was still winding high, it was just cutting out a cylinder or two, but you could tell it was still trying to go higher. It had sort of a POP-POP sound but you could tell by the seat of your pants the engine was trying to still go higher, but the limiter was cutting out random cylinders to stay below the limit.
When I got my car with 3.73 I thought I needed a new transmission. At WOT it would start hick-uping. It would start the upshift then loose engine power then apply power again.
What worked for me was to lower the shift points till the engine did not red line during the WOT shift.
What I was told (right or wrong?) was the mechanical advantage (of the 3.73) was letting the engine do less work so when the command for the shift occurred the engine was already closer to red line than for a stock shift because the car was accelerating faster. When the shift occurred the unloaded motor could hit red line easier because it was just about there before the shift started.
By memory stock red line is 5200 rpm.
Your issue could be your transmission is shifting slow due to wear.
All of this is guessing unless Tom9C1 tells us which car with what motor and rear end are we talking about? And the maintenance history of the transmission?
Stock "wide open" shift points are 5400 on B-Bodies. With 3.73 gears,the motor can hit the rev limit. Especially during the 1-2 shift. Forced downshifts could easily accomplish this as well. Most bump the rev limit up a couple hundred rpm just to be on the safe side. At least I did...
I could pretty easily bounce off the rev limiter on my '94. Annoyingly low rpm even for 2.93 gearing if you ask me.
Bumping RPM up helped quite a 'bit.
Oil light is on and has been since before I changed out the oil level sensor. Seems to die now when it gets warmed up. I suspect that I have a broken or loose wire somewhere from the sensor back into the harness , this might be causing the shut down. Going to fix the light and go from here.
I have had this issue during 3 different events...
Fuel pump going out.. Fuel pressure was 15 PSI. I was running very lean and was hitting the rev limiter. Otherwise didn't seem to run badly.
After swapping in 373 gears I was bumping off rev limiter again until I moved the shift points.
And when transmission started slipping before it went out.
In all cases nothing showed up during normal driving. Just during WOT so checking your transmission fluid levels and condition of fluid as well as fuel pressure should help out.
Optical Sensor ! Auto electrical tech pinpointed right to it. When the OS heats up, it dies ! For some reason when it cools down, starts right back up, Ordered one and will replace OS with Mitsubishi unit. Fu@k me !
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