Why won't my car move?

August 18, 2023 4:03 PM

So, I left my car parked for almost two months while I was out of town. Now the engine starts up but the car will not move and while it's idling the engine revs (1000rpm up to 3000rpm). It feels different in drive, reverse, neutral, and park, but it does not move (and my driveway is on an incline so I would expect it to maybe roll backwards in neutral).

The battery ran down completely while I was gone (unforced error, I intended to unhook the battery but forgot), but I took the battery to AutoZone and got it charged back up and as I say, the car starts just fine. (Could I have dislodged something when I took out/replaced the battery?)

I deliberately left the parking brake off while the car was parked (and put chocks behind the tires) because the brake calipers have gotten stuck before, so I don't think it's stuck brake calipers BUT it does kinda feel like the brakes are on. I did leave the car in park, maybe I should have left it in neutral? (NB: I have definitely removed the wheel chocks.)

I should probably check the transmission fluid but the car is supposed to be at operating temperature when you check the transmission fluid and the revving creeps me out.

The car in question is a 20 year old Honda Element, so, you know, things go wrong with it and there could very well be more than one thing wrong. I was vaguely planning to take it to the mechanic this week anyway for an oil change, general checkup, and air conditioning repair (no AC since last summer, but I don't drive that much so it hadn't bothered me), and I have roadside assistance so getting it towed shouldn't be a big problem.

But I'm very curious and wondering if there's something obvious I'm missing! And also I would kind of like to know whether this is likely to be a car-ending incident (and how, if at all, it's related to leaving the car for two months).

posted by mskyle to Travel & Transportation (19 answers total)

Best answer: I had my car do something like this, but it had a manual gear change.I called a mechanic, who suggested that my handbrake (parking brake?) had stuck and that before paying him to come out I should first try the same thing he'd try first and alternate first & reverse gears a little as though trying to rock out of mud or snow, and try to unstick the brake that way. It worked for me, and the poor chap was saddled with being my mechanic until he retired.
posted by BCMagee at 4:21 PM on August 18, 2023 [4 favorites]

A neighbor of mine had his catalytic converter stolen overnight and he said the next morning his car wouldn't run properly. It's just a thought, I don't know anything about Honda Elements or whether your symptoms could match up with the C/C.
posted by forthright at 4:25 PM on August 18, 2023 [1 favorite]

When you shift to neutral, are you (or a friend) able to move the car yourself at all by pushing?

Engine running + car not moving suggests, if not stuck brakes, then a transmission issue... If you hadn't said it feels different in park/drive/etc then I'd be leaning towards broken shift control.

(I know very little about fixing cars besides having owned some old ones with similar problems)

Man, I miss Car Talk!
posted by hovey at 4:43 PM on August 18, 2023 [5 favorites]

Sorry, I missed that you're parked on an incline, so no need to try pushing in neutral.

Anyway on my old Lincoln, the shifter cable had broken where it attached to the transmission, so no matter what gear you thought you had selected, the thing stayed in park. It had just finally rusted through one day, and was a cheap part to replace. Maybe the computer thinks you're shifting gears so it's having the engine run differently, but the mechanical link is broken so you're just still in park.
posted by hovey at 5:14 PM on August 18, 2023

Response by poster: BCMagee, that was my first inclination - rock back and forth a bit - but I'm wary of hitting the gas too hard while I'm in drive because the car is parked almost right up against my garage door. And I don't think stuck calipers are all that likely since I used chocks instead of the parking brake while I was gone.

I may try to recruit a friend/neighbor to push the car while it's in neutral tomorrow (it's a pretty gentle incline at the top), but I can't safely do it myself because of the layout of the driveway (retaining walls on both sides and significant slope down to the street, neighbor parked on the street immediately opposite my driveway).

And the mention of the catalytic converter reminds me that my tailpipe had been swinging all over the place before I left (one of the things I was planning on having checked out), so for sure something in my exhaust system is loose (though hopefully not missing entirely) which could conceivably explain the weird idling. It occurs to me that the weird idling could have been happening before I left, like the broken air conditioning - I basically never leave my car idling.

This is such a Car Talk question! Sadly back when they were on I drove nearly-new, extremely reliable cars so I never had any interesting questions. Whereas my current car is definitely in its "parts fall off (but mostly not important ones)" stage of life.
posted by mskyle at 5:16 PM on August 18, 2023

It doesn't seem likely that this is the problem, but when I replaced the automatic transmission on my car ('81 VW Vanagon) and started it up for the first time, putting it in gear did nothing: it simply sat there. The issue was that the transmission needed to pump its oil around for a while to fill up whatever it has inside. After letting it idle for quite while everything worked and I could drive it out of our garage.

So I'm thinking just maybe your transmission hasn't pumped its oil around. Have you checked the level of the transmission's fluid? And did you let it idle for a while?

When your car's driving again please update us!
posted by anadem at 7:51 PM on August 18, 2023

I wouldn't think it has anything to do with your catalytic converter. If it was missing, your engine would be EXTREMELY loud, as your exhaust system has essentially been cut away (the cat sits between the engine and muffler). It also would not prevent your car from moving, as the engine and drive train are not involved.

(Source: have had cat stolen twice in three years.)
posted by lhauser at 8:08 PM on August 18, 2023 [2 favorites]

You can still check the transmission fluid even if it's not warm, the reading won't be correct but there should be some fluid on it. If there's none, you've found your problem.
posted by Marky at 8:59 PM on August 18, 2023 [1 favorite]

I have a Honda and when it did something like that, the alternator was bad. It wouldn’t drive backwards it would show fine at first and then drop power. I could start it with jumper cables but it wouldn’t last long.
posted by The_Vegetables at 9:49 PM on August 18, 2023

I had a similar experience to BCMagee, but in my case it was actually the parking brake cable that was frozen.
posted by abraxasaxarba at 10:56 PM on August 18, 2023

Best answer: We had to park a car for longer than anticipated because Covid. Left it parked with the handbrake on. The brake pads rusted to the disks. Needed a rather large hammer to remove the mess.

So if your car is not rolling down the incline in neutral I'm going to say jack up a rear wheel and see if it turns by hand.
posted by wrm at 1:00 AM on August 19, 2023 [1 favorite]

I left a car for several months and it was stuck because of rust, I think on the axle. A tow for a few feet unstuck it.
posted by Mid at 7:16 AM on August 19, 2023

Engine revving weirdly could be a combination of: Trying to deal with two-month-old stale gas; perhaps a critter built a nest in your air intake; perhaps a critter chewed some wiring. If it's "surging", it might be starving for air, or is getting conflicting emissions control readings because wires have been chewed.

Agree with checking the dipstick for your automatic transmission fluid, even if cold. It will read slightly higher on the stick when hot, but in general, you should still be near or in the "safe" zone, usually cross-hatched on the dipstick, even when it is cold. If the car is parked on an incline, this can affect your reading. I had an older pickup with a slow transmission leak, and when my fluid level would get too low, it sometimes just wouldn't go into gear. Do you notice a puddle or anything under the car that might indicate a leak?

Assuming your shift pattern resembles PRNDL or PRND21 or such, I'd let the car run for a bit, and with your foot firmly on the brake, change from park to reverse, give it about 10 sec, then to neutral, wait 10 sec, down to drive, wait 10 sec, etc... all the way down, and then work your way back up. Possibly repeat. Sometimes this can get things going again. But this is assuming you have a near-normal amount of transmission fluid present.

Was also going to suggest having a friend give a gentle or rocking push while in neutral (from the uphill side, obviously), but please do this with the car running and someone at the wheel, so you have the benefit of power brakes.
posted by xedrik at 9:36 AM on August 19, 2023

Response by poster: Update: transmission fluid is not empty. BUT the engine revving thing has only gotten more dramatic and the check engine light came on, so I decided to stop running the engine.

I didn't see (or smell) any signs of rodent occupation, but maybe I'll take a closer look. And I wouldn't have thought the gas would go that stale - I deliberately filled it up right before I left and I'm sure I've gone longer than 6 weeks between fill-ups before, but it's been really rainy, maybe some water got in? I do also wonder whether I could have knocked a hose or something loose while I was taking the battery out.

Pretty confident it's not brake calipers or the alternator because I've had those problems before!

Right now I'm thinking I'll get it towed to the mechanic on Monday. Will update!
posted by mskyle at 12:05 PM on August 19, 2023

I wrote this out before your update - proceeding with my suggestion below might not be the best idea if you've got a check engine light on.

I have a honda, and recently mine would not go in reverse, and it turned out that the alternator was shot. My sister's Honda coincidently did the same exact thing- hers wouldn't go into gear at all. When the electrical system isn't running at full charge it won't operate properly, especially the electronically controlled transmission.

In your case your battery might be done. Or the connection isn't as good as it needs to be. I would start by rechecking that battery connection, and make it extra tight. Then starting and just letting the vehicle idle for a bit. However - most modern Honda's feature a special voltage regulator system (ELD) that won't charge the battery if the engine is only idling and there is no load. What that means is you also need to turn on the headlights, stereo, interior lights, charge a phone etc, or hold the gas peddle to around 1200 RPM. For at least 10 minutes, ideally 20.

That revving could be TPS, the Idle Air Control Valve or another issue with the throttle body, which all could be byproducts of the electrical issues. You also might have knocked one of these connections loose farting around with the battery - some of them are nearby on the air intake, so unplug and plug those back in, or at least give them a look.

If running the machine doesn't reset it then you can check the battery, then test if the alternator is working, and then the ELD module. A multimeter can be used to check the voltage of the battery at the terminals. Base share with car odd should be at about 12.7 v (+/-0.1v). Starting the engine the voltage should dip down to 11 v (+/-), this is ELD controlled. Under load (ie lights) or higher RPM the ELD should turn off and the the voltage at the battery should rise up and then stabilize after a few minutes to around 13v-14v. 14.6 v is the upper limit and sustained high voltage at over 14.8v is also bad.

A bad battery will have a base charge below 12.7
A bad alternator won't be able to achieve correct running voltage of 13-14v
The common indication of a bad ELD will result in the headlights dimming when gas pedal is released.
posted by zenon at 12:27 PM on August 19, 2023

Okay, now that the Check Engine light is on, you can get or borrow an ODB II reader and see what your car is complaining about, and it very well might have something to do with why it won't move.
posted by the Real Dan at 3:28 PM on August 19, 2023

Best answer: I’m pretty sure it’s the brake pads. They have rusted or seized. Hit the wheels hard with a hammer to get them unstuck from the pads. And they will release. I speak from experience.
posted by miles1972 at 8:48 PM on August 19, 2023

Best answer: Most likely your brakes are stuck on - even though you released the parking brake, it's still possible (although much less likely) for the calipers to get corroded to the discs because they're probably just touching the discs and, if the weather has been damp, two months is long enough to cause problems. If that's your only problem, you'd be able to feel and probably hear the car trying to move against the stuck brakes.

That's not the cause of the engine revving though. Apart from idling higher from a cold start, which is normal and should settle down within a minute, this is definitely not normal and is likely a sensor issue. Some sensor or, more likely, a connection to a sensor has got damp and/or corroded and is convincing your car's ECU something is happening that isn't. It's also possible that the car won't allow the transmission to shift into gear above a certain RPM point, so the revving instead of idling could be the actual cause of the car not moving.

Given there are at least two different things wrong and diagnosing either of them is near impossible by text, taking it to a mechanic (or calling a mobile mechanic) seems like the best bet here. Before you do that, do have a look in the area around the battery for a loose or dislodged connector, though.
posted by dg at 6:32 PM on August 20, 2023 [1 favorite]

Response by poster: Y'all were right, the brakes were frozen!

I spent a little while longer trying to figure it out myself, then started calling around to mechanics but my usual guys were slammed and finding someplace new was more inconvenient than waiting a couple of days so I just waited.

When the tow truck guy came he was actually able to get it out of the driveway without towing - just put it in reverse and brute forced it until all four wheels were rolling (brakes were still pretty noisy and there are of course skid marks all over my driveway now - better him than me). Since all the other stuff was still wrong I had him tow it even though it was at least theoretically driveable, and we'll see what the mechanic says about Everything Else.

But as far as the initial question, "Why won't my car move?" goes, this question is answered, and everyone who said "stuck brake calipers" was right even though I 100% didn't believe you - I thought I had been so smart leaving the e-brake off!
posted by mskyle at 2:08 PM on August 29, 2023 [4 favorites]