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Discussion Starter · #1 ·
Hey guys

So my Auto KB 2001 GT has a very rough time accelerating immediately after the shift into 3rd gear.
It almost appears that the rpms drop too low. The rpms drop to around 1400-1600, and if I apply pressure to the pedal, the car runs like crap and rpms do not increase until I gove it heavy gas and it takes off (no noticeale pinging or knocking, but the symptoms of detonation kind of?). I can hear it running like **** by the sound of my exhaust.

Now here’s the weird part. When I drive in the morning to work, the first 3-4 minutes it doesn’t do this at all. 3rd gear the rpms stay nice and high and if I suddenly accelerate, the car goes great. Only after 5 minutes of driving the symptoms start. Also, the symptoms seem worse in the rain.

I assumed the issue was o2 sensors not working via open/closed loop. Unplugged the sensors and took it for a quick drive, symptoms were still there.

Here’s what I have done to find the problem to no avail:
Unplugged (New) oem o2 sensors
Unplugged entire EGR system
Unplugged tps
Cleaned Maf
Cleaned IAC
New COP Boots
New Fuel Filter
New DW 340 lph fuel pump (oem died)


So do you guys think this is a trans issue? Should I change fluid?
I am thinking either trans, bad msd cop(s), or a bad tune.
What else would cause an issue after being warmed up?
No idle issues, no wot issues. Just accelerating after the shift.
Also if i keep the car in 2nd gear, i have no issues at all.
 

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Discussion Starter · #2 ·
.
 

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Not exactly the same problem but i have noticed my 01 with a 1.7 KB is slow to increase in RPM in 3rd also, kinda just hangs around 4 grand for a bit then finally picks up. Not that mine runs poorly at all, I just find it annoying that it wont rev faster but it could just be the nature of the beast.

https://youtu.be/0f14lbjllFA
 

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Discussion Starter · #4 ·
Not exactly the same problem but i have noticed my 01 with a 1.7 KB is slow to increase in RPM in 3rd also, kinda just hangs around 4 grand for a bit then finally picks up. Not that mine runs poorly at all, I just find it annoying that it wont rev faster but it could just be the nature of the beast.

https://youtu.be/0f14lbjllFA
Yeah mine is a lot worse than that. After shifting, the rpms drop and it falls on its face completely. Like sputtering until i pish the pedal hard enough.
But thanks for the help man.

Im leaning towards cops since it happens when the car warms up.
 

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Slo_n_low
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I had a similar issue recently. On highway seemed after I got into 4th (auto 4r70W) it wouldn't want to do any WOT downshifts. If you floored it rpms would just climb very very slowly from like 2500 to 3000. Car has 160k miles and has had a whining trans for a while. And I noticed that in neutral the car revved up easily with no issues. Also, when I would turn off overdrive it would downshift and get some torque back. So I took it in to a shop, I had already bought a TransGo shift kit online. So I had them replace the fluids and filters, and install the shift kit. Total cost was $500 took like 4 hours. But runs great now, which is good because I don't have the cash for a transmission rebuild.

The kit was about $90 from Summit Racing.
https://www.summitracing.com/parts/...s0mxcNNtbMwUzfSwVmJmerpE75G2utJsaAqRBEALw_wcB

---------- Post added at 06:47 PM ---------- Previous post was at 06:43 PM ----------

With bad cops you should hear a popping off sound at idle, lack of power at times, and might get a flashing Check Engine light, with some misfire codes coming up.
 

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Discussion Starter · #6 ·
I had a similar issue recently. On highway seemed after I got into 4th (auto 4r70W) it wouldn't want to do any WOT downshifts. If you floored it rpms would just climb very very slowly from like 2500 to 3000. Car has 160k miles and has had a whining trans for a while. And I noticed that in neutral the car revved up easily with no issues. Also, when I would turn off overdrive it would downshift and get some torque back. So I took it in to a shop, I had already bought a TransGo shift kit online. So I had them replace the fluids and filters, and install the shift kit. Total cost was $500 took like 4 hours. But runs great now, which is good because I don't have the cash for a transmission rebuild.

The kit was about $90 from Summit Racing.
https://www.summitracing.com/parts/...s0mxcNNtbMwUzfSwVmJmerpE75G2utJsaAqRBEALw_wcB

---------- Post added at 06:47 PM ---------- Previous post was at 06:43 PM ----------

With bad cops you should hear a popping off sound at idle, lack of power at times, and might get a flashing Check Engine light, with some misfire codes coming up.
Interesting.
I think i’m going to attempt to switch out cops first. Just because of how easy it is. Tranmission stuff will def be last on my want to do list lol.
That being said, anyone have a spare set of cops you want to lend me for a day or two haha
 
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