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  • 1994 - 1995 Specific Tech

Rpm's Went Up But Car Speed Didn't Increase

  • Thread starter Thread starter Aye_plus
  • Start date Start date Sep 12, 2015

Aye_plus

Member
Feb 28, 2013
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0
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Sep 12, 2015
#1
  • Sep 12, 2015
  • #1
I don't even know how to ask this question much less do a search for it
I drove my car into work today and I noticed this problem recently but today was a good one. When I changed gears to drive away from my house, it seemed as if my speed didn't increase even when I was in 3rd gear, only the RPM's went up. So I'm out the neighborhood, in 3rd gear doing about 30mph and I punch it, just to see what happens....well, the RPM's went all the way up to 5k as if I had it in neutral but the car didn't go any faster?! I've had this 95 for about 2yrs now and it has never ran well. The previous owner removed all emission stuff including the EGR and lowered it.....a lot! It's a good looking car with all bolt on's and about 10k on both the engine and trans. Last time I had a similar problem people were telling me to clean the MAF so I did and it didn't help much. I wasted a whole can of cleaner and it looked the same so I assumed it was clean. It's running a burnt SCT chip from AM and so I'm guessing that's why the CEL doesn't come on and scanners do not work. I've done a KOEO test a few weeks ago and it did throw a few codes but they weren't anything important. Hopefully I have time to remove the chip tonight and run another test. Thoughts, Suggestion regarding this rpm issue?
 

Three50won

10 Year Member
Jul 11, 2010
1,135
64
69
Sep 12, 2015
#2
  • Sep 12, 2015
  • #2
Sounds like a transmission issue to me. Is it a 5 sp or auto? If it is an auto, did you manually try to change the gears?
 

Aye_plus

Member
Feb 28, 2013
46
0
7
Sep 12, 2015
#3
  • Sep 12, 2015
  • #3
It is a 5speed and should have about 10k miles or less. The car also has an upgraded fuel pump and #24 injectors with calibrated MAF with a Fox top swap
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
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Hillsborough county
Sep 12, 2015
#4
  • Sep 12, 2015
  • #4
If it's a 5 speed then more than likely it's the clutch..

It's either gone out on you or the adjustment is wrong.
 

Chythar

Recently finished repairing my rear
20+ Year Stangneter
Aug 26, 2004
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Foothill Ranch, CA
Sep 12, 2015
#5
  • Sep 12, 2015
  • #5
Another vote here for the clutch. I've found with my Cobra clone that, if I floor it when the rpm's are too low, the clutch will slip. In my case, it would slip then catch, so the car felt like it was stuttering a bit. IMO, 3rd gear @ 30mph is a bit low to floor it, unless you've got a strong clutch. Next time, try downshifting to 2nd and punch it. You should be able to accelerate at that speed & gear without punching it, tho.
 

Aye_plus

Member
Feb 28, 2013
46
0
7
Sep 12, 2015
#6
  • Sep 12, 2015
  • #6
Pulled some codes when I got home but I don't think they're very helpful:
327 - DPFE or EVP circuit below minimum voltage of 0.2 volts
511 - EEC permanent Read Only Memory (ROM) test failed
512 - EEC battery powered Keep Alive Memory (KAM) test failed.

Engine on:
412 - Cannot control rpm during KOER high RPM check.
I hope it's not the clutch, I barely has 10k miles and I baby this car when I drive.....mostly because I don't know how to race in a five speed.
 
S

StangRider1

Member
Aug 20, 2005
45
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17
Vancouver, Washington
Sep 14, 2015
#7
  • Sep 14, 2015
  • #7
I'd bet my paycheck it's your clutch. You may baby the car, but the previous owner may have abused the hell out of the car (which is likely, given the modifications you've described). When my original clutch failed @ 90K miles, it did EXACTLY the things you have described... just saying.

Kerry
 

Aye_plus

Member
Feb 28, 2013
46
0
7
Sep 14, 2015
#8
  • Sep 14, 2015
  • #8
If it is the clutch, it going pretty fast. My RPM's were at about 2500 when the car started to move on its own as I tried to reverse out if my driveway.
I picked up some pizzas when I got off work and I parked on an incline. I park the car and leave it in 1st gear and I pull the e-brake. When I get back in to the car to leave, I release the brake and the car begins to roll back. the gear is still in 1st and the car is off, that isn't normal , right?!
 

Chythar

Recently finished repairing my rear
20+ Year Stangneter
Aug 26, 2004
2,373
140
113
Foothill Ranch, CA
Sep 15, 2015
#9
  • Sep 15, 2015
  • #9
2500! That's really high. I try to keep the rpm's under 1500 when I first get the car rolling.
 

Aye_plus

Member
Feb 28, 2013
46
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Sep 15, 2015
#10
  • Sep 15, 2015
  • #10
So do I.
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
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Hillsborough county
Sep 15, 2015
#11
  • Sep 15, 2015
  • #11
It could be one of two things, either your clutch needs to be adjusted or you need a new clutch.

Either way it's still clutch related
 

Aye_plus

Member
Feb 28, 2013
46
0
7
Sep 15, 2015
#12
  • Sep 15, 2015
  • #12
Yeah, after rolling down that incline, it has lead me to believe that the clutch is the culprit. Whenever I hear back from my mechanic, I'll post up the conclusion.
 

Aye_plus

Member
Feb 28, 2013
46
0
7
Sep 25, 2015
#13
  • Sep 25, 2015
  • #13
Could I replace the clutch disc only or does the whole thing need to be replaced? I still haven't had a chance to look into my clutch problem, I'm sure it needs to be replaced though.
 

BrothersPerformance

Premium Sponsor
Sep 1, 2009
261
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28
3060 Performance Circle, Deland, FL, 32724
Sep 25, 2015
#14
  • Sep 25, 2015
  • #14
If you are going to replace the clutch then I would install a new clutch kit. Why put a worn out pressure plate and throw out bearing on a brand new clutch? Also, don't forget that you may need the flywheel resurfaced or replaced.
 
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