Why won't my car start?

November 1, 2006 10:45 AM

Murphy's law at work. My '87 Sentra (auto, base model, 1.6L) won't start sometimes. 3 mechanics failed to diagnose. (but didn't fail to bill me). What's going on?

This intermittent problem is making me crazy. Once in every 2 weeks, say, I get power to all devices, but it won't turn over or even click. 1987 Nissan Sentra, auto, base model, 1.6L, in Canada.

I have ruled out the following:

-- 1 Mechanic replaced the starter and flywheel flexplate. No effect. $1000 bill.
-- Another replaced the battery terminal wires.
-- Another replaced the inhibitor relay.
-- Twisting and shoving the (automatic) shifter in P and N every which way has no effect.

Every time I have this problem, AAA comes, declares there is no voltage to the starter, and starts it up for me using their voodoo magic. Then I drive to a mechanic. But of course, by the time I get to the mechanic, the car starts up like a charm, every time. So they have nothing to go by. Hence the 3 false and expensive diagnoses.

I know it could be one of 3 (or more) things: the ignition switch, the neutral safety start switch, the starter solenoid, or some random wiring. But at the prices my dealership charges for parts and labour, I can't afford to replace them all on spec.

Suggestions much appreciated. Thanks. These questions are similar but not the same, and don't help me:
http://ask.metafilter.com/mefi/41826
http://ask.metafilter.com/mefi/41426

posted by graytona to travel & transportation (16 comments total)

it's not the battery is it?
posted by Sassyfras at 10:51 AM on November 1, 2006

If it's your solenoid, you will know. It normally makes an awful sound when you (try to) start your car up.
posted by Holy foxy moxie batman! at 10:56 AM on November 1, 2006

It's for sure not the battery, every AAA guy that's rescued me has tested that first! Thanks though.
posted by graytona at 10:59 AM on November 1, 2006

So, next time it wont start, I would suggest you try to get a mechanic to come and look at it there. My mechanic promised that the next time I have a coolant leak that has been undiagnosed after numerous unproductive visits he would come to me. Maybe you could get the same deal?
posted by sulaine at 11:06 AM on November 1, 2006

I don't know if your 87 Sentra was anything like my '94, but the starter solenoid on my '94 was integrated into the starter itself. If it is the same, and they replaced the starter, they got the solenoid at the same time, so that's not likely to be your problem.
posted by deadmessenger at 11:14 AM on November 1, 2006

Call Click and Clack! they're the only reason I wouuld ever look forward to car trouble - I've wanted to call in for years!
posted by AthenaPolias at 11:31 AM on November 1, 2006

Honestly? An '87 Sentra probably isn't worth fixing. Some electrical problems are notoriously hard to diagnose, especially intermittent ones. No point in throwing good money after bad.
posted by electroboy at 11:34 AM on November 1, 2006

The neutral safety start switch would be my guess.

How does the starter switch feel? If it's stiff and you feel like you really have to exert a lot of force to turn the key, then my bet would change to the starter switch.

One thing I would suggest is to find a reliable independent mechanic and stop taking the car to the stealership. Those guys are looking at your car and seeing boat payments.

And, yeah, what electroboy said. An '87 is pretty much on the edge for "should I drop money on this thing?" decision-making. The $1000 you just spent is easily over 1/3 (1/2?) the value of the car. But, then again, it's paid for and cheap to operate (barring these expensive repairs)
posted by Thorzdad at 11:47 AM on November 1, 2006

I disagree with the arguments that an '87 Sentra isn't worth fixing - they're great, long-lasting and reliable (in most cases!) cars.

I bet this is going to be a simple fix involving a relay of some sort. Find a mechanic who will take the car and drive it to work for a while. Even two weeks if necessary. When it finally fails on him/her, the problem will be more easy to trace.

Of course, I had an 81 Volkswagen Rabbit many, many years ago whose fuel system would occasionally decide not to work, causing it to crank and crank without starting until the battery died. I tried letting the mechanic drive it, and he drove it for a month without anything going wrong before returning it to me and declaring it fixed by magic. It wouldn't start the next day.
posted by M.C. Lo-Carb! at 11:57 AM on November 1, 2006

I have an 85 Nissan Sentra that did this periodically for a while. It finally did this at a gas station that had a full service garage. I talked to the mechanic on duty, and he suggested I hit the starter with a hammer. I thought he was joking, and told him I'd like to do just that out of frustration, but he wasn't kidding. He hit it with a hammer a few times, and then told me to try it. It started right up.

The explanation I got was that heat and other factors can sometimes make things that need to be free to rotate stick to the inside of the motor. A jarring impact can free them.

I carried a potato sized rock in the vehicle for a few months which I'd use to bang on the starter motor when it didn't work. Every time, it'd start right up again.

Until the time it didn't, anyway, at a crucial moment when I needed to catch a flight, which I missed. After that, I just got it replaced.

Electroboy is quite probably right, though. Apparently mid-80's Sentras are pretty prone to intermittent and odd electrical problems. Mine still has one that no one's worked out that can make the car entirely undrivable in certain conditions.
posted by weston at 12:24 PM on November 1, 2006

If the AAA guys can get it to start reliably, it might be worth asking them exactly what "voodoo magic" they're doing and reporting that to the mechanic.

(In effect, the AAA guy is a mechanic who is accurately diagnosing your problem -- take advantage of that.)
posted by mendel at 12:52 PM on November 1, 2006

Hum. Next time it won't start try this: Turn the key forward into the start position. Then use a jumper cable to connect to the positive terminal on the battery. Then try touching it to the terminal on the starter and see if it cranks. If so then you could just install a seperate switch for starting. (I have a household light switch in my rusty old van).
posted by jeribus at 2:09 PM on November 1, 2006

I'd search the NHTSA site for recalls and complaints of similar make, model, year exhibiting same symptoms for ideas on what it could be.

If the ignition switch is the problem, here is what I wrote down when I was dealing with a defective ignition switch on a 2000 Honda Accord, which no mechanic could diagnose. After reading through the NHTSA complaints, I had the dealer replace the ignition switch, which solved the months-long mystery. See if your symptoms are similar enough:

a) battery needed recharging. re-started when charged. same scenario, 3 incidents over a 7-day period.
b) Attempted to start engine starting from a parked position, heard the engine turn on, disengaged parking break, shifted gear from 'park' to 'drive', then noted lack of response to accelerator, nor the break, leading to realization that engine had quietly died down. Restarted engine was able to continue. replaced with new battery. 3 days later, same scenario.
c) 1 day later, engine died while on road, when breaking slightly to follow the curve of the road. Car would continue to roll, following any decline/incline of the road, with gear in "drive" position, and breaks not responding, until I force the gear to "park", force the parking break. The point at which the engine dies is often not immediately noticeable, as car will continue to move due to built-up velocity. Green, "interlock key light" on dashboard will light.
d) Incidents are increasing in frequency. Engine re-start is becoming less immediate, often having to attempt turning the key three or more times before the engine will restart. Mechanics A, B, and C had problems reduplicating problems on demand and could not diagnose. Often goes days without reduplication problem. Was told that diagnostics show the car in good working order.
posted by MD06 at 3:09 PM on November 1, 2006

this may not be of any help, but my 98 saturn wouldn't start sometimes either. in the morning, it would start. in the evening, it would not. i took it to a ton of mechanics.. got the fuel filter and fuel pump replaced.. and it turned out it was the temperature sensor. good luck :)
posted by kerning at 4:08 PM on November 1, 2006

I'm clueless about cars so my apologies if this bit of information is completely inapplicable to your situation but: My Nissan Maxima seemingly randomly failed to start (eventually I noticed it was more likely to fail after it had rained), and sometimes it would die while on the road only to start several minutes later. It turned out I needed to replace the distributor cap (something about moisture accumulation).
posted by crack at 7:32 PM on November 1, 2006

I vote solenoid. They don't always make noise at failure. A solenoid is a switch for large currents. It uses a small amount of juice to switch on and off a large amount of juice. Sometimes it just jambs. And solenoids are not always part of the starter.

I would call around and see if one can be had from a junkyard. They may even install it for a few extra dollars. The employees that pull them off may install it as a side income. You won't know until you ask.
posted by kc0dxh at 8:23 AM on November 2, 2006