# Intermittent poor performance on '97 Altima



## Cooperman (May 18, 2005)

About two weeks ago my '97 Altima started having problems where the idle speed would drop (to nearly stalling), surge, and then repeat this a couple of times before stalling altogether. 

I took it in to get looked at and they told me the knock sensor was faulty and it needed a tune-up. So they installed a new knock sensor and tuned it and after that it ran fine for a week before it started happening again - only this time there was an extra problem. When I'd be driving, there'd be no acceleration when I hit the gas and then a few seconds later it would accelerate - it was very jerky. The rpm's would also surge and drop sporadically as I was driving. 

It only started doing this once my gas tank was heading towards empty - and I know for sure I'd filled up with regular 87 octane gas at a station I've been told has poor quality fuel. 

I took it back to the mechanic and he said it might be contaminants in the fuel and to put in a higher quality fuel and see how it went. So I filled it up straight away with 93 octane fuel and the improvement was immediate! It drove so smoothly. 

The next day I drove to work and it was fine - and then on the drive home in the afternoon it started to have the same problems again. It stalled as I was driving along so I pulled over and tried restarting it and it was running really rough. I turned the engine off for a few minutes and then tried again and it was fine again and got home (a few miles) without further incident. 

Do I just have a dirty fuel system, maybe water in my tank or is something else likely to be causing it? I just hate taking an intermittent fault to a mechanic because it never does it while you're there and it takes them ages (and lots of $ down the drain) for them to find the actual problem.


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## Agoudine (Feb 19, 2005)

There may be problem with fuel pressure. You need equipment to do that. When ti is hard to find out what is wrong with the car, I prefer to take it to a dealership - you will pay under $100 for professional diagnostics instead of paying for unnecessary part replacements that a mechanic will suggest,like your knock sensor,that could not be a problem in your case and costed you around $200 to replace. Dealership will also try to pull as much money out of you as possible by telling you to do repairs that you don't need,but they will tell you for sure what is causing the problem.
There are some things you can do yourself : buy Haynes Repair Manual online or in autopart store for about $15 and do some troubleshooting yourself. Read the trouble codes on your On Board Diagnostic System and identify the code with the manual or online,or ask us here. Autozone or other store can do it for you also. It's FREE. A mechanic does the same think,but charges for it.
I don't know what kind of tune up they did,but you may want to replace fuel and air filters , spark plugs, wires,distributor cup and rotor. All parts are relatively cheap and you can do it all yourself with the manual.


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## LONDONDERRY (May 19, 2004)

Has the CEL been scanned for any stored codes, because from what your discribing, it sound like wither your cam sensor in the distributor is going bad or you have a clogged fuel injector. To test the injector place the tip of the screw driver on the injector and then place your ear on the other end and listen if they all sound the same, if not then you have a bad injector. Keep me posted.
Frank


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## Cooperman (May 18, 2005)

The place I took it to checked for codes and all that came up was the knock sensor. Having just checked the paperwork they gave me, they changed the spark plugs, distributor rotor and distributor cap. They also did an injector service so I'm assuming the injectors are fine.

The problem has now happened every afternoon this week on my way home from work. The stalling is now always preceeding by some seriously bad hesitation when accelerating. Yet somehow I managed to do a 100 mile roundtrip last night without incident - even after it was bad yesterday after work.

Even after it happens, if I turn the engine off for a few mins it'll be fine afterwards.


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## LONDONDERRY (May 19, 2004)

Cooperman said:


> The place I took it to checked for codes and all that came up was the knock sensor. Having just checked the paperwork they gave me, they changed the spark plugs, distributor rotor and distributor cap. They also did an injector service so I'm assuming the injectors are fine.
> 
> The problem has now happened every afternoon this week on my way home from work. The stalling is now always preceeding by some seriously bad hesitation when accelerating. Yet somehow I managed to do a 100 mile roundtrip last night without incident - even after it was bad yesterday after work.
> 
> Even after it happens, if I turn the engine off for a few mins it'll be fine afterwards.


Your knock sensor is being cause by something else.
Sound like your distributor is going. Altimas are notorious for having these problems. Have Nissan determine this for you. Shop mechanicas have problems trouble shooting this.


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## Cooperman (May 18, 2005)

I've been finding that it's worse when the weather is warmer.

I think I'm gonna have to bite the bullet and take it in to get checked out soon. Although I think I'll wait until the end of the month when I get paid because I have the feeling it's gonna be one of those things that's really hard to find what's causing it and it's gonna cost me a fortune paying someone to track the problem down and fix it.


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## Aussie_Dan (Aug 21, 2004)

First things first, i would be changing the fuel filter.....
if it is full of crap, it may be able to flow enough fuel whilst the car is cruising, but under load when fuel demand is higher, the fuel may not be able to get through the filter fast enough, so the car will hesitate.
Dan.


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## Cooperman (May 18, 2005)

UPDATE: The Nissan service place has had it a day and a half now and they don't know what's wrong with it. Of course, the problem hasn't occured in the time that they've had it!! They suspect the distributor is failing but have yet to prove it. I'm collecting it tonight and will see how it goes over the weekend. $20 says on the way home from picking it up it'll stall


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## Cooperman (May 18, 2005)

Well it didn't do anything on the drive home, but I drove it today and within 5 mins it stalled. The Nissan guy said I had an after market distributor in there which I'm thinking is the cause. I just wish I knew for sure that was what is causing the problem. I might let Nissan have it again for a day and see if it'll act up while they have it and then decide what to do.


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## erik2282 (May 17, 2005)

could it be a problem with the throttle position sensor?


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## Cooperman (May 18, 2005)

So Nissan had it for 3 days in total and it didn't stall once on them. They suspected it was the distributor so I got them to install a new one. Drove it home and it was fine. The next day (yesterday) I drove it to work and back (15 miles each way) and it was fine. This morning on my way into work I was on the interstate and after about 10 mins I could feel it starting to hesitate. About 3 mins later I hit some congestion, slowed down to a few mph and the engine stalled!

Managed to get off the road with what little momentum I had. Restarted it straight away and it stalled again without my foot on the gas. When I revved it, it lacked power. Waited a few mins and restarted it and it was fine and got me the next 5 miles to work without incident. The check engine light doesn't come on before stalling.

Any ideas?


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## Cooperman (May 18, 2005)

I thought I'd update where I am with this problem.

So I got the distributor replaced. It ran much better for about a 7-10 days after I got it done. It did stall twice during that time but other than it performed much better. The dealership told me I had an aftermarket distributor in the car that the previous owner must have put in. So I got a new nissan distributor put in and things did improve significantly for a short period of time.

Then things started getting bad again. I could feel the engine hesitating and the revs would drop when coming to a stop at lights. I'd have to shift it into neutral and rev it to prevent it from stalling. There were a couple of instances where the engine was severly lacking power, making it almost undrivable! Yet, if I pulled over, turned the engine off for a few mins and it would restart fine.

So last Sunday I checked for codes and there weren't any. I figured changing the fuel filter couldn't do any harm. It's cheap to do and at least with a new one I could rule that out as a potential problem. 

Only problem was I had real trouble getting the hoses off the old one. After about 15 mins of trying I gave up because I didn't want to pull too hard and damage anything. The next day however the car ran really well! But the following day it was bad again. But it got me thinking that perhaps in my tugging on the hoses, the fuel filter (which may have been clogged) temporarily became unclogged. 

So the next day I took it into Jiffy Lube - it took them well over an hour to change the fuel filter because of the stuck hoses. They eventually got it done and I've been driving it for 3 days now and it's the best it's run in 2 months! Hasn't stalled once, hasn't hesitated once and I'm hoping the problem has been fixed for good.


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## Asleep (Jan 19, 2003)

Cooperman said:


> I thought I'd update where I am with this problem.
> 
> So I got the distributor replaced. It ran much better for about a 7-10 days after I got it done. It did stall twice during that time but other than it performed much better. The dealership told me I had an aftermarket distributor in the car that the previous owner must have put in. So I got a new nissan distributor put in and things did improve significantly for a short period of time.
> 
> ...


this is the reason why im always saying to START CHEAPLY. you never dive right in and pay for the most expensive "fix". your problem sounded like a fuel problem from the get-go. i wish i had noticed this thread earlier. now would be a good time to have your tank drained and flushed. if it was that bad that it clogged up your filter, im sure theres more stuff in there.


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## Cooperman (May 18, 2005)

Well I talked too soon. After three days the problem came back last night! For about 2 mins it was trying to stall and was severly lacking power when I was at some lights. But after revving hard in neutral to keep the engine running it got through the rough patch. 

As an aside, about two weeks ago the fuel gauge stopped working correctly. It doesn't really fall with the needle staying to the Full side until I get to probably 1/3 of a tank left (estimate based on mileage).

AsleepAltima, is this another sign that says dirty fuel tank or unrelated?


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## Asleep (Jan 19, 2003)

Cooperman said:


> Well I talked too soon. After three days the problem came back last night! For about 2 mins it was trying to stall and was severly lacking power when I was at some lights. But after revving hard in neutral to keep the engine running it got through the rough patch.
> 
> As an aside, about two weeks ago the fuel gauge stopped working correctly. It doesn't really fall with the needle staying to the Full side until I get to probably 1/3 of a tank left (estimate based on mileage).
> 
> AsleepAltima, is this another sign that says dirty fuel tank or unrelated?


i cant remember if the altima has a filter sock on the pump in the tank or if its just a pick up tube, but it might behoove you to pull the pump under the backseat and check it out. sounds to me like something is in the tank or in the lines. replacing the filter helped, but i cant help but think something else is in there. back in the day for a good prank, we used to drop a tampon into someones gas tank. the tampon would clog the pickup tube during normal driving and stall the engine. then when the engine died, the lack of suction would allow the tampon to float away from the pickup tube... when the car started, it would do it all over again. your car sounds like that.


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## Cooperman (May 18, 2005)

It has a filter sock on the pump. The car was back at my local nissan dealership yesterday and again it didn't stall for them. They pulled the fuel pump and the filter sock was clean.

They kept the car overnight and this morning I went up there and took the car out with the mechanic working on it - of course it didn't stall! But I'm happy I got to talk to the mechanic rather than the foreman and I got to explain to him in detail what had been happening rather than him hearing it second hand from the foreman.

After we got back from taking it for a drive he checked out the EGR valve - he said it was fluttering open as soon as he opened the throttle. The valve sticking open would fit the symptoms - running rough at low rpms/stalling. So he disconnected the vacuum rube to it and I drove it to work this morning to see how it went. He also checked the EGR pipe for deposits but it was ok. It was ok on the drive to work but I still felt it was lacking the power it should.

When I went to drive it home after work 5 mins into my journey it started hesitating, revved low and tried to stall. I pulled over and "massaged" the diaphragm. When I lifted it the car died as expected. So I "massaged" it for a few minutes thinking it might not be sealing properly which would cause my lack of power and if the leak got bad it would cause it to stall - the story fits.

After doing this the car was revving 100rpms higher than before at idle (where I kept telling the mechanic it should be!) and it had that power it was lacking - the responsiveness when accelerating that it was missing.

Soooo... I think I'm gonna track down a replacement EGR valve and see how it goes.


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## KA24Tech (Feb 2, 2004)

Well I've been away for awhile but thought I would chime in on this one to start. It sounds like the Idle Air Control (IAC) Valve, Mass Air Flow (MAF) meter, or the previosly mentioned EGR valve may be the culprit. When it starts to stall or stalls try unplugging the MAF to see if the idle stabilizes. If it does then you have found the problem. The EGR should be pulled, after purchasing a new gasket, to check and clean out the carbon that typically clogs the passage. The carbon usually impedes the operation of the valve. The IAC has a more complex series of tests so we will cover that if needed later. You may try running a can of 44K from BG with a tank of premium to clean it out as well.

Troy


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## Cooperman (May 18, 2005)

Should disconnecting the MAF increase the idle speed? The problem is when it goes to stall I can't pop the hood, get out of the car and disconnect it before it dies. 

This morning it hiccuped again for a few mins. I pulled over and it stalled before I could disconnect it. Tried restarting it straight away and it wouldn't start. I disconnected the MAF and it started ok. Reconnected and it stalled. Restarted engine with MAF connected and it started - idling around 600rpm. Disconnected the MAF and idling increased to around 750.

The EGR valve is still disconnected too. I find it hard to believe the valve could open enough to make it run rough and stall by itself without it being connected. I mean yeah if it was connected it could quite possible stick open after getting up to highway speed... but surely not when it's disconnected because it's not opening at all! I don't know... maybe it can?

I think I might just replace both parts. The EGR valve is cheap enough, although the MAF is a substantial expense.


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## jserrano (Oct 27, 2004)

Check for a dirty fuel pump filter, a sticky EGR valve, and intake manifold leak.


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## Cooperman (May 18, 2005)

My car has been running without stalling or any problems now for a week and appeares to finally be fixed. Here's what I did for those interested...

I noticed that when I wiggled the connector on the MAF the engine would die. I regrounded the MAF and there was no improvement so I got a replacement MAF from a used parts yard for $120, put it on and bingo! Hasn't stalled since.


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## KA24Tech (Feb 2, 2004)

You gave the classic symptoms of what happens when the MAF goes bad when you unplugged it and plugged it back in... I'm glad the problem seems to be resolved.

Troy


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## jserrano (Oct 27, 2004)

You might also want to check the EGR and MAF systems.


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