Stalling on a hill climb
May 19, 2010 11:10 AM   Subscribe

What does it mean if my manual-shift car is having trouble taking off in first gear, up a steep hill?

Let's say I'm stopped at an intersection on a hill in Seattle, like a 15-17% incline.

Lately, I really have to gun the accelerator to get the car going, or it will either stall or fall backwards. If I gun it, the wheels spin before they grab the road and pull me forward. Either way, it is embarrassing and seems a somewhat sketchy way to get up a hill.

It's been getting gradually worse, which is why I'm wondering what's up.

I'm really hoping this isn't the clutch on its way out, but if this is symptomatic of a dying clutch, I'd also be curious if a car with 63K miles should need a clutch replacement this early, and what would be involved in terms of cost of repairs.

(I know how to do hill starts using the emergency brake, but I'm hoping not to have to get into that habit. Thanks for any advice.)
posted by Blazecock Pileon to Travel & Transportation (33 answers total) 1 user marked this as a favorite
 
I'm confused. I thought using the emergency brake was the correct way to do hill starts. How do you stop yourself rolling backwards at all without it?
posted by EndsOfInvention at 11:12 AM on May 19, 2010


I can usually swap between the brake and accelerator pedals fast enough that the car doesn't roll back too far.
posted by Blazecock Pileon at 11:14 AM on May 19, 2010


Do you engine brake instead of using your brakes? That can wear the clutch out faster than normal.

You should always use the brakes instead of engine breaking, as it is cheaper to replace the brakes than the clutch, and the added "safety" of engine breaking is a myth.
posted by Grither at 11:15 AM on May 19, 2010


Yeah, the handbrake is your friend. Stop thinking of it as the 'emergency brake' in a manual car; if you've been relying upon your clutch skills alone from a cold start, you may well have knackered it before its time.
posted by holgate at 11:23 AM on May 19, 2010


Either use the hand brake or roll your right foot onto the accelerator without taking it off the brake pedal. Rolling back is the problem - that momentum is what's causing the wheelspin.
posted by The World Famous at 11:30 AM on May 19, 2010


If you want to check your clutch, park on a flat surface, step hard on the brake, and let out the clutch with the engine idling. If the engine doesn't die right away, the clutch is slipping and on it's way out.
posted by hwyengr at 11:31 AM on May 19, 2010 [1 favorite]


Your hill starts, if done very frequently, could actually erode the clutch rather quickly. Has the "grip" point on the pedal changed since you've had the car? Is the point larger or smaller? Yes, my first thought is that it's a clutch.

If not, your car could just have lost some power, and if you haven't had a tune-up in some time (new plugs, timing adjusted, etc.), that would be the most obvious culprit.

I have no idea what car this is, but you might be able to get away with a new clutch for $600ish.

Start using your hard brake.

(Also, engine breaking actually puts wear on the transmission, not the clutch (clutch getting no more action than shifting in general), and even the Car Talk guys say it's a wash between the two and you should just go with what's comfortable for you.)
posted by General Malaise at 11:40 AM on May 19, 2010


I thought using the emergency brake was the correct way to do hill starts. How do you stop yourself rolling backwards at all without it?

Left foot off brake, onto clutch.
Quickly, bring the clutch up to the engadement, while simultaneously giving enough gas to hold the car without stalling or slippage.
When you can proceed, lift left off the clutch to full engagement while pushing the accelerator with the right.

It's awkward at first, but quickly becomes natural. It's much faster than the handbrake method. Whith practice you can do it on high inclines, with foru-wheel drives, etc...

I've been driving manual gearboxes for 25 years, four or five cars, one to twelve years old and never replaced a clutch for wear. I replaced one once because the engine seal at the transmission went.
posted by bonehead at 11:48 AM on May 19, 2010


I don't think it is the clutch. You state, "I really have to gun the accelerator to get the car going, or it will either stall or fall backwards. If I gun it, the wheels spin before they grab the road and pull me forward." If the clutch was going out, the engine wouldn't stall and you would be less likely to lay rubber on your starts. This sounds like a loss of power in the engine which could be from any of a number of simple or tragic causes. When was the last time you checked your air cleaner? Do you notice white or black smoke coming from the exhaust? Is there an oily residue around the end of the exhaust pipe?

As to the question of whether 63K is too soon for a clutch to go out, no. Clutches wear based upon the type of driving and the type of driver involved. The mere fact that you start from a stop at the bottom of a hill a lot can reduce clutch life. Spending your life on the Interstate would extend clutch life. If you "ride" the clutch... Well, you get what I mean.

Start with the clutch test hwyengr suggests and then go to a mechanic for a compression test and computer check.
posted by Old Geezer at 11:50 AM on May 19, 2010


Sorry.

first step: is right foot off brake onto accelerator.

I am not now, nor have I ever been an advocate of being a two-footed driver (left brake, right gas). Shudder.
posted by bonehead at 11:52 AM on May 19, 2010 [1 favorite]


General Malaise: "(Also, engine breaking actually puts wear on the transmission, not the clutch (clutch getting no more action than shifting in general), and even the Car Talk guys say it's a wash between the two and you should just go with what's comfortable for you.)"

Interesting, Straight Dope must've misquoted them: "Among the more vocal exponents of the don't-downshift school are Tom and Ray Magliozzi, hosts of the radio show Car Talk. These guys admit you should downshift when driving down a long hill; otherwise your brakes heat up so much that the brake fluid boils and you lose your ability to stop the car. But on all other occasions, they argue, downshifting does nothing but wear out your clutch faster. "
posted by Grither at 11:52 AM on May 19, 2010


I use 2nd gear when starting from a full stop on inclines. Have you tired that?
posted by cestmoi15 at 12:02 PM on May 19, 2010


If you want to check your clutch, park on a flat surface, step hard on the brake, and let out the clutch with the engine idling. If the engine doesn't die right away, the clutch is slipping and on it's way out.

Awesome. I'll give that a shot.

Do you notice white or black smoke coming from the exhaust?

Every now and again I get white, sweet smelling smoke from the exhaust. Not much, and it doesn't happen too frequently. Apparently this can mean that I have cracked head gaskets and that it is leaking coolant into the engine, but as far as I can tell, the coolant levels are staying constant and the engine temperature meter on the dash doesn't go anywhere near the caution point.

This is a 2001 Saab 9-3, btw. Most of my driving is highway. I don't ride the clutch, except in occasional stop-and-go rush hour-type situations. I've driven stick shift my whole life so unless I've learned some bad habits from my folks I think my manual shift skills are probably typical.

In the last few weeks I have done a lot of city driving, moving things to our new residence, so I've had to do a lot of Seattle hill climbing when going back and forth. It's something I have noticed more frequently of late.
posted by Blazecock Pileon at 12:04 PM on May 19, 2010


On steep hills I give it a certain amount of gas as a constant and let the clutch out slowly, "riding" it to a slight degree instead of simultaneously trying to adjust the gas and clutch pressure. My Honda is 17 years old and still on the same clutch (knocking wood).
posted by bonobothegreat at 12:08 PM on May 19, 2010


I use 2nd gear when starting from a full stop on inclines.

I can't imagine how that would help. In fact, it'd probably make the problem worse.

At hte risk of a slight derail, now that I have a car with hill-start assist, I'd never do without it. It's like having a third foot.
posted by timeistight at 12:10 PM on May 19, 2010


Do you engine brake instead of using your brakes? That can wear the clutch out faster than normal.

You should always use the brakes instead of engine breaking, as it is cheaper to replace the brakes than the clutch, and the added "safety" of engine breaking is a myth.


This is complete and utter rubbish.

There will be essentially zero extra wear on your clutch as a result of engine braking. Once the gear is changed (the same wear - ie negligible- as any other gear shift, up or down) the engine is connected to the gearbox in exactly the same way as if you were driving. With no slip between clutch and gearbox (ie your foot isn't on the pedal) clutch wear is zero. Engine braking is significantly better than freewheeling or slowing down in a higher gear. The extra control element, reduced wear on your brakes and 'free' braking force are all benefits. There is no downside to engine braking, if performed correctly (ie not too early that the engine over-revs).

I'd be fairly certain that this is nothing at all to do with the clutch. While it is possible that the clutch produces a 'grabby' transition to transmitting drive, I find this unlikely.

There is no reason, in addition, to start making statements about 'start using the handbrake'. Rolling backwards doesn't create any more drag on your clutch to pull away - the handbrake only stops you rolling backwards while you figure out how to pull away, it does not in ANY WAY make the start up a hill easier on any component, just gives you more time to balance the bite point. It is only the 'correct' way to hill start because the given technique of catching the clutch at its biting point and pulling away without it is a lot harder to do and outside the skill set of a lot of drivers. It is only harder on the driver, not the car. As long as you are not holding the car on the clutch on the hill, but just pulling away, there is absolutely nothing wrong with this technique.

The issue remains an issue needing addressing (rather than a technique criticism), because BP states that the car has changed in its behaviour. I'd suggest that there is something wrong with the engine that has meant it is producing less powerr or running slightly rougher at lower rpm - the car either doesn't have the power to pull away (hence stalls) or it needs to much (revs, hence...) power applied to do so that it often breaks traction instead of pulling away smoothly.

I'd suggest an electrical service (plugs, coils, wires as appropriate) and possible air filter and other diagnostics. The car isn't running right, and all this talk of clutches is a complete distraction and (majority wildly inaccurate and) poor advice in this instance.

BP: Can you think of ANY other changes in the car behaviour? How long since last service? Anything at all - even if you dismissed it as irrelevant and/or unconnected since this happened or before. Do you have to downshift for hills you didn't before? Does the car stall sometimes on flat ground?
posted by Brockles at 12:11 PM on May 19, 2010 [4 favorites]


very now and again I get white, sweet smelling smoke from the exhaust. Not much, and it doesn't happen too frequently. Apparently this can mean that I have cracked head gaskets and that it is leaking coolant into the engine, but as far as I can tell, the coolant levels are staying constant and the engine temperature meter on the dash doesn't go anywhere near the caution point.

It can also mean a whole other number of things. On a 2001 car with 63,000 miles on it (especially a Saab) I'd suggest head gasket issues are unlikely.



cestmoi15I use 2nd gear when starting from a full stop on inclines.

Don't do this. You're killing your car, and this will never, ever help.
posted by Brockles at 12:15 PM on May 19, 2010 [2 favorites]


Have someone with years of driving manual transmissions drive your car and see what they say. A slipping clutch is pretty obvious. If it's not a slipping clutch, you've either got an issue with the car losing power just off idle for whatever reason, or you you need a driving lesson.

I don't endorse use of the e-brake on hills. It's bad form, and if you're good with the clutch you don't need to do it. Starting the car from a standstill on a hill only increases the wear on the clutch by a small factor. Using the e-brake doesn't hurt anything per se, but if you need it on hills you're probably also wearing your clutch unnecessarily even when you're not on hills.

Re: engine braking: The clutch never wears when the car is in gear, kinda by definition. When the car is in gear, the clutch is not doing anything but sitting there. 99% of the wear comes from engaging it from a stop and the other 1% from the slipping done when you change gears without perfectly matching the engine to the road speed. You can change gears just fine without the clutch if you're particularly gifted (I'm not).

I also really, really doubt that wear on the transmission from engine braking is that significant. Most transmission wear comes from changing gears and damaging syncromesh, not wear on the teeth themselves. On overrun/engine braking you're wearing the reverse faces of most surfaces anyway.
posted by pjaust at 12:16 PM on May 19, 2010


I suppose it *is* possible that you've got a clutch that isn't engaging smoothly due to the linkage itself. But I'm with Brockles on this being user error or engine control related.
posted by pjaust at 12:20 PM on May 19, 2010


I'm with Old Geezer - if the car either stalls or spins the wheels, you do not have a problem transferring power from engine to wheels.

Your problem might be not enough power to begin with. That's a little odd in a SAAB - they're not necessarily muscle cars, but they usually have decent power. (Is it a turbo?) Power issues can come from old air or fuel filters, dirty injectors, and any of a number of electronic fuel/ignition system sensors. Have you tried an OBD test? Autozone will give you an OBD reader for free for a day or so, and that can save you a lot of money in diagnostic work if it's an electronic problem.

But it seems more likely that it's just technique: when the car is trying to roll backwards and you're hurrying to halt & reverse that motion with the clutch, it's harder to apply power in the smooth, just-right fashion that the vehicle needs. I know you've been driving stick forever, but if you're not used to these inclines, this might be the whole problem. So I'll throw in another vote for E-brake starts on hills. My dad taught me that it's the right thing to do on steep hills, because it reduces wear of clutch & engine mounts, and increases your control of the vehicle.

(Oh, and if it's getting worse, what about tires?)
posted by richyoung at 12:28 PM on May 19, 2010


Just to make this clear, this issue is NOT a worn or slipping clutch. It can't be, because stalling the engine and/or spinning the wheels are the two things that become increasingly difficult to do as the clutch wears. They are the exact opposite of a worn clutch symptoms.

There may be an issue with clutch engagement, but it is an outside chance and (to my mind) unlikely.
posted by Brockles at 12:29 PM on May 19, 2010


(Oh, and if it's getting worse, what about tires?)

Bingo. Chirping the tires on a hill start is one of the signs I use to figure out when it's time for new tires.

To add to the chorus, hand-brake for steep hill starts is perfectly fine until you figure out the source of the problem. I end up hand-braking a fair bit, because I live on a pretty steep hill and drivers in Boston like to think they're saving time by edging up until they're three-quarters of an inch off my rear bumper at the stoplight. I don't care how fast you can get your foot from pedal to pedal, on a 15% incline, your car is going to roll backwards a small amount.
posted by Mayor West at 12:41 PM on May 19, 2010


BP: Can you think of ANY other changes in the car behaviour? How long since last service?

I had the oil and oil filter changed a month ago, at 62.5K. My mechanic used synthetic oil. I don't remember the weight.

I had a 60K service (new cabin filter, coolant flush, etc.) done a year ago at around 58.5K (I don't drive much). I had a heater core replacement at the same time, because coolant was getting into the cabin, on the windshield and into our lungs. I also had a new serpentine belt and an oil sludge kit installed, because sludging is an issue for Saabs of this model and the belt was in rough shape.

The car has had trouble starting strongly ever since that major service, where it takes a few more seconds for the engine to start, but two mechanics couldn't replicate it and the car otherwise eventually starts and runs okay, once warmed up.
posted by Blazecock Pileon at 12:43 PM on May 19, 2010


Grither - That episode was about down-shifting in a manual car.


From an episode with a manual: "Neither engine braking nor hunting will do your car any harm, Tom. It's really just a question of preference, Tom. Which one do you find less annoying?"
posted by General Malaise at 12:49 PM on May 19, 2010 [1 favorite]


Every now and again I get white, sweet smelling smoke from the exhaust.

This is actually a pretty tell-tale sign that you're leaking coolant into your engine. It might be slight, but it's real. How's your gas mileage?

(P.S. The only reason I was hesitant to say it was your car losing power earlier is that you'd have to lose a lot of power for this to happen. But, if your plugs aren't sparking right, your timing's off, and you're leaking coolant, well, then it could be the case)
posted by General Malaise at 12:53 PM on May 19, 2010


To concur with Brockles, if you're getting wheelspin then your clutch is fine. If it can transfer enough torque from a dead stop to make the tires brake traction, then it's likely in good condition. If you floor it at a low speed in 2nd gear and the engine revs before you accelerate of if the car shudders, then the clutch is worn. When a clutch wears out, it no longer executes its primary function of transferring engine torque through the drivetrain.

If you're finding that you have to rev the engine to a higher RPM to generate the necessary power to motivate the car from a dead stop on a hill, then the engine must be making less power at low RPMs then it has in the past.

The white smoke out the tail pipe isn't always a leaking headgasket. There could be a leak that allows some coolant into the intake manifold. Many throttle bodies have coolant circulating through them to prevent throttle plate icing (even on new vehicles). Some intake manifolds also have coolant passages that help regulate the intake air charge temperature. Also, if your Saab is turbocharged, the coolant that passes through the turbo could be leaking through a seal and is getting sucked into the intake system. Bad turbo seals often result in leaking/burning coolant and oil as well as a gradual loss of power.

If the engine is burning coolant, that coolant will certainly contaminate the oxygen sensor which is responsible for accurately reporting the air/fuel mixture to the engine computer. If that mixture is incorrect, then there will be a corresponding loss of power.
posted by Jon-o at 1:19 PM on May 19, 2010


So, a slipping clutch isn't what's going on here. Your car is having trouble starting when cold (when it has to work harder) and is having trouble producing power on a hill (under load.) And you're getting white smoke from the exhaust.

Hunt down the coolant leak, and fix it, and only then (if the hill problem still persists) should you look for other solutions.

and yeah, starting from rest on an uphill incline in 2nd gear is just putting the car under a heavy load and making you burn the clutch up faster. Don't do this.
posted by davejay at 1:38 PM on May 19, 2010


I would like to posit that if you smell the sweet maple smell of vaporized ethylene glycol then that means you have an external leak (e.g. leaking hose causes coolant to drop onto hot manifold) and not a more serious internal leak (e.g. cracked head gasket causes coolant to be sucked into cylinder.) The reasoning is that when it goes out the tail pipe you don't smell it; when it vaporizes in the engine compartment do you.

As a SF resident and long time manual transmission driver, I have to say that it should be dearly obvious when the clutch is slipping. The tell-tall sign is that you are accelerating and see the tach shoot up for a few seconds and then settle and feel things connect. It's definitely a 'sense' kind of thing but if you don't sense it then it sounds like the clutch isn't slipping.
posted by Rhomboid at 2:52 PM on May 19, 2010


How's the tread on your tires? My car was very overdue for a tire change and I would frequently get some wheelspin even at fairly modest RPMs when taking off from a stop. New tires -> no more wheelspin. The peelout RPM went from ~2.5-3k to ~5k just like that.
posted by mullingitover at 4:37 PM on May 19, 2010


The Saab is a FWD car. I checked the tires and the front treads are down to 4/32 and 3/32. I'm going to replace them tomorrow and see how it goes.
posted by Blazecock Pileon at 5:24 PM on May 19, 2010


Ok, the tyres aren't the issue just as much as the clutch isn't. It has nothing at all to do with the issue.

The problem isn't that the OP cant pull away without wheel spinning, the problem is that he can't pull away normally because the car stalls. When he tries to pull away EXTRA SUPER HARD the car will finally pull away, but sometimes wheel spins in the process.

The wheelspin is unrelated. It's a result of trying to drive around the problem.


BP: The car will be more likely to pull away without wheelspinning, as it will have more grip, but it will still stall if you try and drive away normally. It won't fix anything. The poor starting and low power is where you need to spend your money if your tyres are still legal (I don't know what your legislation is).
posted by Brockles at 5:37 PM on May 19, 2010


A clutch in Seattle is a pian, but clutch cars rule. There are awesomely difficult intersections in that town for clutch cars.

You probably just need a tune-up. Nothing shows off the bad tune like starting on a hill. When the clutch goes it loses grip. This does not sound like that. Sometimes when it goes it gets a little sticky, and it could be that, but that is less common.

Overthinking comes into play as well. Just the other day on my ride home from work I was thinking about how easy it is to start on a hill yet how difficult it seemed a few decades ago. Then I stopped on a very steep hill. Rather than the regular automatic movements I started thinking about how I was going to get started. All that overthinking led to an epic stall. I start up the hill from a dead stop on this hill about every other day and never stall, except that one time when I started thinking about it.
posted by caddis at 12:51 AM on May 20, 2010


New front tires have helped immensely with handling and with getting up hills. There's one intersection I still need to try, but it looks like old tires were at least part of the problem.
posted by Blazecock Pileon at 4:16 PM on May 20, 2010


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