Car needs to rev higher and higher to accelerate

honda
accord

#1

Honda Accord 1994 EX

Problem: over past two weeks (around 200 miles) car’s acceleration became less and less effective. Need to rev car to higher and higher rpms to accelerate and shift into higher gears. Now it’s hard to get up a hill, in 2nd gear at 5000 rpm.

I don’t have a compression tester.

  1. Car starts fine. No pings.
  2. Exhaust blows fine and no smoke.
  3. Checked for vacuum hose leaks, none at all.
  4. Spark plugs look fine, there’s no oil in spark plug wells.
  5. No check engine lights. ’
  6. Oil on oil stick normal color.

But …

  1. Recently coolant ran low. But engine temperature never shot up.
  2. Recently (over 2 weeks) oil went from full to near empty. Oil light didn’t go on.
    Lights on my dash work (abs, brake, etc.)

Given loss of coolant and oil, I though it would be blown gasket. But spark plugs and wells look clean, and there’s nothing whitish in oil. Maybe coolant and oil loss are due to running car harder to accelerate.

If cat was clogged, would exhaust blow well? If I drill hole in front of cat, will it run normal? (don’t worry, I’ll get it changed, or fix it.)

If fuel pump the problem, wouldn’t I hear it on start up?

If battery and/or battery cable bad, wouldn’t car have trouble starting and reving up?


#2

If it has an automatic transmission, have you checked the level/color of the tranny fluid?

Tester


#3

If your engine is running at 5000 rpm in 2nd gear and you can’t get up a modest hill I suspect you either have an automatic transmission that is slipping or a manual transmission with a burned up (slipping) clutch.

I’d suspect that a 20 year old car running 5000 rpm will begin to consume some oil and perhaps run hotter than usual.


#4

When was your last transmission fluid and filter change? Betting no recollection.


#5

It’s manual. Recently changed air filter. Transmission fluid is clean. Fuel filter, pump, been a while. Car has rebuilt tranny, installed 2 yrs ago. Would all gears suffer at the same time? If its slave/master cylinder, how come pedal is good?


#6

You’re showing all the classic symptoms of a slipping clutch. Get on a flat level road. Come to a stop. Accelerate, starting in 1st, shift to 2nd as you normally would, then shift to 5th and floor the accelerator. If the RPMs go up but the car doesn’t move faster you need a new clutch.


#7

@asemaster is on it. Bad clutch!


#8

Like others I was assuming slipping transmission or clutch from the get go. The thread title says it all. That’s still what I assume it is.

But then the description has some ambiguity in it. This part says slipping clutch (now that we know it’s a manual): “Need to rev car to higher and higher rpms to accelerate”.

But this part is ambiguous: “and shift into higher gears”

You can shift into a higher gear any old time. So what happens if you do? Pulling a hill at 5000 rpms in 2nd gear is probably about right if you’re doing something like 60mph up a hill - though why one would leave it in 2nd gear I don’t know, but you can since its probably not redlined. So when you’re pulling a hill in 2nd gear at 5000 rpm what kind of speed are we talking about? What happens if you upshift? Does the car just lose power so you have to downshift again?

Or are you hitting 5000rpm in 2nd gear while trying to maintain something like 20mph up a hill? That’s certainly the clutch.

As I said, I’m still assuming slipping clutch, but wondering about power loss.


#9

" Would all gears suffer at the same time?"

In a manual, there is only one clutch and whether its slipping or not has nothing to do with what gear you’re in (though it would vary according to engagement rpms).

"If its slave/master cylinder, how come pedal is good? "

This kind of issue has nothing to do with those parts. It would be that the clutch disk is worn out. The pedal and cylinders have to do with simply engaging and disengaging the clutch - not with how much friction material is still left on the clutch disk.


#10

Loss of oil, clutch slipping. Are they related? Maybe rear main seal leaking oil onto the clutch plate?


#11

“Loss of oil, clutch slipping. Are they related? Maybe rear main seal leaking oil onto the clutch plate?”

Could be, would be an easy oil leak to fix with the transmission out. But sounds like pretty soon the thing won’t move any more anyway, oil and coolant leaks aren’t really an issue if the car doesn’t drive!


#12

Thanks, acemaster, keith, cigroller, knfenimore… appreciate the knowledge.

One thing. Is there a way to diagnose RMS leak prior to transmission removal? On Accord 94 m/t.


#13

If the RMS is leaking enough to explain your low oil episode then there will be plenty of evidence at the back of the engine where it mates to the transmission. If its only leaking a little there might not be much evidence of it. But if you do verify that the clutch is slipping, it doesn’t matter much since installing a new one is a good idea with the transmission out anyway.


#14

Thanks. I’m not going to remove transmission myself. Will take in.


#15

My '05 Civic was experience an issue that sounds identical to this. I also assumed it was related to the transmission. If I put my foot down, the engine was racing to the higher RPM’s very cleanly, but the car was moving much slower and climbing hills was a real chore. It’s an automatic, but it literally felt like when a clutch is slipping in a manual.
On the highway, I could reach a max speed of about 55mph and it took about 45 seconds to go 0 - 55.

Turns out it was that my Catalytic Converter had become plugged. Immediately after having that replaced (expensive), the car runs like new.