95 Max - Engine Shudder, Exh Sputter, & Stall Symptom while idling @ stop

[OrigJunior]

Folks,

With my 95 Max (125k miles odometer) warmed up after driving a few miles I experience the following intermittent problem.

When stopped at a stop light with brakes depressed and engine idle @ 650 rpm, engine will suddenly shudder, exhaust will sputter, and the idle will fluctuate up and down between 650 down to 450 rpm as if it wants to stall a couple of seconds and then resume normal idle. The same thing happens intermittently when stopping after driving into a parking stall or when placing car in reverse while attempting to correct parking into stall.

Car will otherwise accelerate normal and driving is unaffected. Itll only happen intermittently when idle returns to 650 rpm at a stop.

Plugs have been changed last year. I don't know what else to do but take it into the Dealer's Service. Anyone have any helpful ideas? Help!!

[aidan2474]

Read my post, after time you might experience the symptoms worsening.... then again maybe not...

[chuckie311]

check to see if you have a vacuum leak. i had the same problem

[SHIFT_]

Mine jumps all the way to 1100 then back down to normal. I also here a loud sound when pressing the brakes and letting go.

[OrigJunior]

Folks,

Took car into local mechanic and they checked out fuel, emissions, electrical, ignition (plugs/lining, etc) systems and found things ok. THey did, however, find that the EGR Valve is not actuating fully and only opens/closes halfway. They recommended this be changed at a est cost of $200 for the part alone. Does anyone know if this "EGR" valve is important and be the cause of these problems? There is another valve that the mechanic mentioned about having a small hole in it. I don't recall the name of the valve but its est cost was about $100 dollars.

Boy, these imports are high on the parts costs these days. This reminds me of the time my EIC Valve replacement at $500 part cost at the local dealership plus $200 for labor.

Perhaps its time to switch to a local brand of vehicle; however, you can't beat the imports reliability rating. Otherwise, my car has been a sweetheart. I'm leaning towards a replacement with the Toyota Camry.

[thoboyz]

Well, I'm sorry to hear that you're not a TRUE Maxima driver...only TRUE Maxima drivers would respect the Nissan brand and always buy a Nissan...

Anyways, what are you going to do with ur 95 Max after turning your back on Nissan and buying a TOYOTA!......Thinking about selling it?

[xilinx69]

TOYOTA? HA!!!!!!!!!!!!!!!!!!!!!!!

[OrigJunior]

Folks,

Ok, spent my hard earned $ with the Mechanic who replaced EGR Valve, EGR Selonoid, and also cleaned out the fuel injectors and throttle body for my 95 Max (125k miles). It worked for a couple of weeks.

Just recent, it began again. After the car is fully warmed up esp after driving around town stop and go traffic, the intermitent problem began while at idle at a stop light in gear (auto). RPM gauge would flutter and engine would sound/feel like it wanted to stall. This problem would last about a second or two. If I shift the gear to nuetral to take load off of engine, it would stop.

I called the mechanic who stated I leave the car with them for a couple of days to diagnose the problem. THey figured it might be something to do with the electrical ingition system.

Does anyone have any advice? Appreciate any assist as I'd like to keep unto my Max as long as possible since the body is still in great condition, engine does not leak, and except for the problem, its otherwise running steady and reliable.

[aidan2474]

It may be the air flow meter, thats what it was for me

[Knight4]

Wow, I thought it was just me that had this kind of problem! Sorry to hear about your frustration, I know just how you feel. Mine will even be so bad as to stall periodically when sitting at idle at a light or when shifting into reverse to back into a parking space. Really sucks when the light turns green and you're frantically trying to restart your car and get it to shift into gear without stalling.

Mine will behave this way for a indeterminate period of time (i.e. might be a few days, might be a week). Then it will run fine for weeks, so is very intermittent and thus hard to diagnose. I've never been able to figure out if it is related to outside temperature, engine temperature, humidity, etc.

Mine is a '94 SE. I've done the VTC grounding thing and know that the knock sensor is bad (no money or time to replace that right now).

I'd really love to get this problem fixed and will be very curious to hear ideas about what is causing this.

-- But I would never dream of giving up the max --

[aidan2474]

knock sensor was cheap, a few bucks off ebay and changed it myself within about half hour to 45 mins. goto xxx.maxima.org, they how to's on how to do most things. But like I said b4 I had a shop tell me it was not the MAF or as the techs call it the Air Flow Meter, but it really was the problem. They also said it was my engine temp sensor. So those two things should be checked. My problem started out the same way , Once in a blue moon, then it got worse, then wouldn't happen for a while, .. blah blah blah

[Knight4]

From what I've read, on the VG30DE you have to pull the intake manifold off to get to the knock sensor. You did that and re-assembled in 45 minutes???

Also, btw, I've already replaced the coolent temp sensor and the thermostat - thinking that this problem was temperature related. Each time, the problem went away for a time, then came back again.

This seems to be a common occurance as I've kept up with both this and the maxima.org forums...a problem will go away for a while when a part is changed, then will come back again. Apparently, the onboard computer has to re-calibrate itself for the new part and this takes a few trips???

[OrigJunior]

Folks,

Ok, where exactly is the AIR FLOW METER and how much does it cost on the market?

As for acronyms, whats a VTC or MAF? Is the knock sensor expensive and require alot of manhours to fix? Any estimates on this knock sensor as well?

I left out a bit of info, but, this particular problem began after a shop had replaced my headcover gaskets which were leaking oil (125k miles). I assumed they had to remove the intake manifold and associated parts located above the headcovers. If there is a vacuum leak, I have no idea which rubber hose/line that would be. If there was a crack in one of the vacuum line, could that be the culprit?

[Knight4]

Hey, I'm still in nooby status myself, but consider myself to be a student of these engines - pretty much from necessity since repair rates and parts are both expensive and it's hard to find a shop you can trust (it also seems like so many times a car will come back with something else broken ).

The MAF (Mass Air Flow Sensor) can be purchased for 3rd gens at http://internetautomart.com/ for $165 + $30 core. The dealer price will be considerably higher. This sits between your air filter and the throttle body and measures the air flow into the engine. Through a process I don't fully understand, it also compensates for altitude and humidity - I think basically from the density of the air.

The Knock Sensor (about $145 from the the same source as above) is located internally in the engine - different places on different engines (on the 3rd gens, depending on whether you have the single cam or dual cam, for instance). On the VG30DE (dual overhead cam), it is located underneath the intake manifold which has to come off. My mechanic told me that the book they use indicates 4.5 hrs of labor for this (for my DIY abilities, I'm figuring double ). This senses a knocking condition in the engine and will retard timing to compensate. I'm not sure at all what happens when this doesn't work at all. I've been told on another forum/post that the computer will go into "safe mode", whatever that means.

The VG30DE also has two VTC (Variable Timing Cam) gears which will adjust the timing under different engine loads and RPM's. These typically go bad after so many miles and are extremely expensive to repair - hence a lot of guys just disable them by grounding them out.

I've re-read your original post and realize that you have a '95 - thus 4th gen Maxima. I don't think any of the VTC issues are of a concern to you, but the MAF and Knock Sensor do exist on virtually any engine and will serve the same purposes.

Hope this helps...

[Knight4]

My bad...I need to replace all references to the VG30DE...should be VE30DE.