# 97 Altima stalls, bucks & sputters



## shayak_b (Aug 9, 2006)

Hi guys. I'm a newbie, and posted this on some other threads and was advised to start my own thread. Here's my problem. My 97 Altima has 90k miles on it. A month back it started doing this weird thing when it would stall at idle. The tach would go wild, and ultimately the engine would just die. This would happen erratically. Over the last month, this has become more frequent, to the point where the engine starts wanting to die out about 2-3 minutes after being started up. Also, if I drive at cruising or highway speeds at the time it's doing this, I experience bucking, sputtering and occasional loss of power. There's also black smoke and the smell of fumes from the exhaust which tells me the engine is running rich. I've showed 2 mechanics, and got a new distributor, IAC, temperature sensor and even a new Mass Air Flow sensor. None of those have helped me out. I'm at my wit's end about this. Any suggestions or recommendations would be really helpful!!!


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## shayak_b (Aug 9, 2006)

Also... I forgot to mention this.... there are no stored error codes, and the Service Engine light is not on, which is making debugging extremely painful!


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## Asleep (Jan 19, 2003)

you need to check the temp of the catalytic converter before and after the cat. sounds like it may be plugged... if not the cat, then check the voltage on the tps and also, when was the o2 sensor last changed out?


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## shayak_b (Aug 9, 2006)

AsleepAltima said:


> you need to check the temp of the catalytic converter before and after the cat. sounds like it may be plugged... if not the cat, then check the voltage on the tps and also, when was the o2 sensor last changed out?


I'm going to try and check the voltages on the O2 sensors and the TPS this weekend. I should be able to do it with just a voltmeter right? I don't know when the O2 sensor was last changed out since I bought the car only about 10k miles back. Can you tell me in a little more detail though what a plugged cat. might do?


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## Asleep (Jan 19, 2003)

yup, you can check the voltage using a voltmeter. its actually pretty easy to do. heres the instructions on how to do it. 
http://www.240sx.org/faq/articles/throttle_position_sensor_adjustm.htm

good tip - use a straight pin (like the kind for keeping fabric in place during sewing) and poke them down into the terminals being careful to not let them touch. this will give you a good place to check the tps voltage without tearing up the tps harness.

a clogged cat will create lots of problems with driveability. reduced gas mileage, power - driving in general will suck.

you can tell if its clogged because the inlet to the cat will be noticeably hotter than the outlet side - it may even be glowing. you can probably also tell by the absence of exhaust pressure from the tailpipe. im not positive that this is your problem just yet - just something to check that doesnt involve paying someone.


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## shayak_b (Aug 9, 2006)

AsleepAltima said:


> yup, you can check the voltage using a voltmeter. its actually pretty easy to do. heres the instructions on how to do it.
> Throttle Position Sensor Adjustment
> 
> good tip - use a straight pin (like the kind for keeping fabric in place during sewing) and poke them down into the terminals being careful to not let them touch. this will give you a good place to check the tps voltage without tearing up the tps harness.
> ...


Hi. I finally got around to doing all the tests on the car. This is what I came up with. The TPS sensor works fine. It goes all the way from 0% at idle to 88% on full throttle. At least, that's what the data flow from the comptuer says. What is interesting is the O2 sensor readings. The rear O2 sensor reads almost as much as the front O2 sensor with a small difference of only about 0.02 volts. Is this normal? Logically it seems the rear O2 sensor should have a much smaller reading than the front O2 sensor. If this is not normal, what could be wrong?


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## Carlicky (Jul 14, 2006)

Hi Shayak and everyone else,

My 93 Altima SE has had these same problems, on and off, for a few MONTHS now... I've been lurking, reading these posts (and all similar ones), and I thought I'd share my experiences. 

My problems started IMMEDIATELY after getting an oil & air filter change, and whatever else those monkeys at Mr. Lube (here in Canada) do. That was probably 4 or 5 months ago. My mechanic is sure that that's purely coincidental, but there you go. The car, mechanically, anyway, was running perfectly all through last fall, winter, and spring.

Generally, lots of power on the highway, sputters and stalls (after warming up) while stopped and idling. Sometimes when it's feeling especially cranky, it will act up a bit while driving - not shifting up when it normally should. When acting up, the exhaust is smoky and raw-fuelish, and my mileage is down about 20-25%.

It's not a vacuum leak (I've already had one nasty gasket repaired), and the car has been to the mechanic 3 times, where the first time he fixed up some corroded-looking cables to the MAF sensor, the second time the car behaved perfectly fine while at the garage (of course), and the third time, he replaced a coolant sensor. Every time the car came back, it would run GREAT for a few days to a week, then the problem would come back. My mechanic's approach at the time was that he would start by replacing sensors, starting from the cheapest to the most expensive (he told me the MAF would be a $500-$600 job ($CDN). So the visits have been pretty cheap, if frustrating.

Following another message thread here on the forums, I thought the 02 sensor was the culprit, so I bought one, but I wasn't able to get ahold of the special ratchet bit needed to install it in time for a long camping trip I was going on, so I rolled the dice and went with the car as-is. As I was leaving my camping trip, my car, overnight, went from being it's normal self, to not being able to start... and I'm pretty damned sure I didn't leave any electrical stuff on. I managed to get back to Toronto on battery-boosts from kind strangers. Even after 3+ hours of solid driving, the battery wouldn't hold enough of a charge to crank it. So when I got back, I bought a new battery. 

I tested the old battery, and it was down around 10.X volts; not knowing too much about this stuff, I guessed that was a bit too low to crank the engine. The alternator, while running, was throwing over 14 volts, so I figured it was fine.

I installed the new battery, and lo and behold, the car ran GREAT for two weeks. I began to suspect that my problems might somehow be electrical related - perhaps there's a short somewhere. My left headlight and running light haven't worked since the end of the winter, and the bulb is fine, so I know there's at least one electrical issue there. Yeah, I know, I'm a slack mofo car owner leaving these things as long as I have, but I don't have a lot of time (or experience) to track this stuff down, and I don't have much money to pay someone else to do it.

Oh yeah, the two weeks - one more thing there - there were a handful of times that I noticed the RPMs drop very suddenly while at highway speed, then come back. But otherwise, the car was fine. Then the sputtering and stalling came back, just as bad (or worse) than ever, with the cranky acceleration too. And that's where I'm at right now.

But I need to do something about it in the next nine days - I just found out that in addition to renewing my Driver's License and license plate sticker, I'm also required to take the Altima for emissions testing... and I think we all know how that would go with smoke billowing out the tailpipe. A friend of mine also thinks that the catalytic converter might be damaged or need cleaning, and it should go without saying that I'm reaaaaallly dreading this repair bill.

So wish me luck and I'll let you know how it goes. Cheers.


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## shayak_b (Aug 9, 2006)

Carlicky said:


> Hi Shayak and everyone else,
> 
> My 93 Altima SE has had these same problems, on and off, for a few MONTHS now... I've been lurking, reading these posts (and all similar ones), and I thought I'd share my experiences.
> 
> ...



Good luck mate!!!


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