jgcable

1997. 130K miles. Automatic. I have owned this car for 6 years and has been absolutely trouble free. Doesn't burn a drop of oil, quiet, powerful, everything works and I maintain it religiously.
Here is what happened.
2 days ago.. out of the blue... the car started missing and bluish white smoke that smelled like gas was billowing out of the tailpipe. I took it to my local reputable repair shop. When they looked at it he told me it threw a 300 code that read misfire. He felt maybe an injector was stuck. He told me he would do a compression and a leak down test and let me know in the morning. This morning he called to tell me the battery was dead so he charged it and when he put it back in and rescanned it the code it had thrown was clear. He checked the plugs, the O2 sensors and everything including the compression, a leak down test and he tested all of the injectors and he charged the battery and everything looks to be in spec. He had the car running for over 30 minutes and it runs great BUT... it is still burning oil out of the tail pipe. He suggested that I change the oil to full synth or an oil that is good for motors that burn oil and maybe install a new battery considering it was dead this morning. He said low voltage could cause an injector not to fire. What I can't understand is this... I have been driving for over 35 years and I have never seen an engine that would go from not burning any oil ever to an engine that is constantly belching oil smoke yet runs perfectly. My wife picked the car up today for me and she said it is running great but it is still smoking but only about 15% as much as it was when we dropped it off. Could there be something else I should be looking at? This one has me stumped.

Fakie J Farkerton

iTrader: (51)

Pintle caps on the injectors need checked, and probably replaced.

The wizard has a thread on this that sounds pretty similar.

http://injector-rehab.com/shop/Nissa...intle-Cap.html

jgcable

The mechanic told me he checked the injectors and they are all fine.

JvG

You know what burning oil smells like. You mentioned that it smells like unburned gas, so it is.


One of your injectors is leaky.

jgcable

I never saw the car. My daughter had the problem yesterday. When she called me to tell me it was missing and smoke was pouring out of the tailpipe I immediately thought it was a BHG but when she told me it smelled like gas and that the coolant was full I immediately thought stuck or faulty injector. She took it to the repair shop. The mechanic that looked at it told me that it was bluish white smoke and that it was oil burning.. not gas.
The first thing he thought it was is a bad or leaky injector. That's the first thing he checked. That's what I thought too. He told me all the injectors both front and back are fine. He told me that if an injector was bad or leaky he would see it in the 02 sensor readings. They were perfect.
Here is a stupid question I guess.... could it possibly be a faulty or stuck PCV valve? He didn't mention anything about checking it and I do know that in the past.. if a car had a bad PCV valve it would cause it to burn oil or smoke through the tailpipe or even the crankcase breather.


Also.. he did mention that 2 of the plugs had some oil on them but not enough to cause a misfire.


This is what I think.. I think that she had an injector not firing correctly because of a voltage condition due to the battery possibly being on its way out. Because of this.. that cylinder loaded up with fuel and now that the battery is charged and its no longer missing what we are seeing is residual unburned fuel coming from the exhaust. I plan on dropping the oil and putting in a high grade.. possibly synth or at least a synth blend... into the motor and installing a new battery after I get it load tested of course.
I am also going to change the PCV valve.

Fakie J Farkerton

iTrader: (51)

And if that doesn't work check the pintle caps on the end of the injectors.
It's easy to miss a broken piece or two unless you're looking for it specifically.

CS_AR

I had broken pintle caps on cylinders 2 and 5. The intake plenum had to be removed to correct cyl 5. I bought a kit and refurbished all 6 injectors with new screens, o-rings, and caps. The kit cost $34. The injectors tested good before I refurbished them. The dealer completely missed the issue and declared my 73,000 mile engine to be bad. I had the car towed home from the dealer and fixed it myself.

Alaskus

Gotta link to that injector rebuild kit?

CS_AR

I will send when I get home. On mobile right now. I found on eBay from CS Performance.

Fakie J Farkerton

iTrader: (51)

Oh, NOW someone is interested in what I said.

CS_AR

To Fakie's point about pintle caps.

Here's a link to the injector kit seller.. Check with the seller to make sure the kit still comes with new pintle caps. I didn't see pintle caps in the picture so I ordered a bag of caps. Then when I received the kit it also had caps. I now have more pintle caps than I will ever use.

http://r.ebay.com/ctqj8K

Youtubes video about injector removal.

Note: After I remove the caps, I use penetrating oil and spray it around the injector top to help loosen it up so I can turn it in the rail for removal. One of the videos mentions WD40.

I use this approach for removing injectors.

https://www.youtube.com/watch?v=LcLVoURrMD8

Other reference videos..

I use a pair of vice grips to break the Phillips head cap screws loose.

https://www.youtube.com/watch?v=MhXwr1diD80

https://www.youtube.com/watch?v=hxrhkdob0B8

I do not reuse the Phillips head screws. I pick up some metric socked head cap screws from Lowes or Ace Hardware to replace the Phillips head screws. Notice in the picture that that Fuel Pressure Regulator (FPR) is new. If I go to the trouble to refurbish the injectors, then I replace the FPR also.




Here's a picture of broken pintle caps that resulted in uncontrollable flooding. Now that I remember it I had spark plugs that smelled like gas and they turned black quickly.

The dealer said: "oh the injectors are just fine -- you need a new engine".

Note: Since the injectors must have been bad for a while before I refurbished them, the catalytic converters were cooked and clogged up. Yes one problem leads to another. I installed a Warpspeed Y pipe to delete the upstream catalytic converters and replaced the downstream cat with a Magnaflow High Flow cat that I also purchased from Warpspeed.

The Wizard

iTrader: (43)

Yup, I'm in agreement with you guys. Sounds awfully familiar to my story of my fuel injectors

https://maxima.org/forums/4th-genera...ite-smoke.html

rexrodriguez

Im also leaning towards broken pintle caps

jgcable

So I got home tonight and I checked the motor out for the first time. I removed the PCV valve and I cleaned it out. It wasn't clogged but it rattles alot more than it did when I removed it. Anyway.. I started the car. I revved the motor. Not a drop of smoke coming out of the tailpipe. The engine purrs like a kitten as it has for the last 6 years. I am going to drop the oil on Saturday and put a synth blend in it along with some fuel injector cleaner. I am also going to get the battery load tested. What oil do you reccomend? Car has 130K on it. Its an automatic and its always babied and never driven hard. Mechanic mentioned full synth. I am thinking blend.
BTW.. I just changed the oil about 200 miles ago. The dipstick oil still looks perfectly clean. I wonder if I should even change it?

jgcable

I got the battery load tested and it tested bad. I replaced it. I also added a can of fuel injector cleaner and some STP oil additive. I started the car and it started to smoke out of the exhaust. It smelled like oil. Bluish smoke. Not a ton but it was DEFINATELY smoking. I took it for a ride around the block a few times and it seemed to start smoking less. I took it on the highway and opened it up to around 90mph for about 4 miles up and back to my house. When I got home there wasn't a spec of smoke coming out of the pipe. My daughter took the car to work.. no smoke at all. She drove the car about 40 miles that night and it isn't smoking at all anymore.
Go figure... I wonder what was wrong?

jgcable

This entire issue really turned into a mystery. The car no longer smokes and it runs great with no issues. Go figure? I wonder what it was that caused the car to suddenly start missing and spitting out ALOT of blue smoke out of the tailpipe? All I did technically was replace a battery that had a bad cell in it.

max-nutcase

Apples and oranges here but

I used STP oils add. on a mower, a few yrs ago, and put a little in it every time since..doesnt burn oil or smoke no more...rings maybe?..they usually dont crap out and all of a sudden n smoke....but im kinda stumped!

jgcable

Me too. I doubt highly that its rings because it got much better by itself PRIOR to me putting in the STP oil treatment. It literally went from a motor that has run flawlessly for the last 6 years to a motor that was missing and belching oil smoke like a crop duster back to a motor that is running flawlessly again. The only thing I did was replace the battery and put in a can of STP oil treatment. I also cleaned the PCV valve but it was already rattling when I removed it so it wasn't clogged.
I am totally stumped.

jgcable

Big problem tonight. After 3 weeks of flawless driving with no smoke or no issues at all the car suddenly started hesitating, gas smelling smoke started coming out of the tailpipe and the car eventually stalled and will not restart. I am having it towed to my house now. Any suggestions? I am really stumped on this one!

The Wizard

iTrader: (43)

Could be the fuel pressure regulator now...and/or the injectors as previously mentioned.

gen1

Check fuel pressure regulator.
Pull the vacuum line off and check to see if gas is leaking through the diaphragm.

jgcable

Would the fuel pressure regulator cause the unburned fuel coming out of the tailpipe in the form of smoke?

The thing I don't understand is if it the fuel injectors how do I tell which one if I can't get the car started? Also... I am doubting its the pintle caps because the car did the exact thing a month ago and has been running perfect since. If a pintle cap or caps were cracked or bad they wouldn't magically clear themselves up.

This is what happened tonight. Started the car up to go home from work and when it started it felt a little rough. As I was driving I started to smell gas really bad and I noticed smoke coming out of the tailpipe. The motor stalled and it won't restart. The check engine light is not on.

The Wizard

iTrader: (43)

A bad FPR will definitely cause what you described in post #19. Happened to me a few months ago.

jgcable

And just so I am clear on this... to check the FPR I disconnect the vacuum hose and if there is fuel in it its bad? Also... is it typical for an FPR to suddenly crap out and then just as suddenly work perfectly for almost a month and then to suddenly crap out again? The car has never experienced any issues at all ALTHOUGH... my daughter said it has been taking a few more cranks to start than usual.


Also.... all the things I am reading regarding a bad FPR is hard starting, stumbling, stalling etc...
This car experienced none of these symptom until it suddenly started hesitating and spitting out gas smelling smoke out of the tailpipe. The repair shop found nothing wrong with the injectors although he thought it was an injector issue. He said the scanner showed everything OK including the test on the O2 sensors. Its not losing compression and there is no BHG. He said it was possible that the battery had a bad cell in it and it was causing an undervoltage condition that screwed up one of the injectors. The next morning I replaced the battery (it was tested and shown to have a bad cell) and the car ran perfect with no issues other than my daughter telling me it took a few more cranks to start than usual for the few weeks. Suddenly, last night the car is doing the exact same thing again except this time it stalled and it would not restart. There is no check engine light. If the FPR was electronic I would think an intermittent issue might be present but as far as I know.. the FPR is mechanical. That would mean it either works or it doesn't work... right?


I am just trying to formulate a plan of action when I start working on it tomorrow.
1st step.. remove the vacuum hose from the FPR and see if there is fuel present. There shouldn't be. If there is... replace it.
2nd step.. remove the spark plugs and check to see if any of them show signs of a bad fuel injector. Hopefully if it is a bad injector its one of the front injectors so that I don't have to take the intake manifold off. If it is a bad injector should I rebuild them or replace them? I read where I can do a check on the injectors with my Fluke meter. The mechanic told me he already did that and they all tested out fine.


I suppose that's the only 2 things I could check at this time.

jgcable

When it happened to you... what were your symptoms prior to you replacing it?

The Wizard

iTrader: (43)

While driving, my max stumbled, then stalled and wouldn't restart. Had to have it towed home. Just what you said in post #19.

One day prior to this, my max stumbled a few times while driving but never shut off.

Your mechanic didn't rip off the manifold and actually physically check the injectors, right? I still think this needs to be done. And besides, he only tested them while you're idling, not under load, right?

Check those sparkplugs for how they look and how strong the smell is on each one. On my max, the strength of smell of gas correlated to the bad injectors.

jgcable

I removed all the plugs. They are all dark brown or black. None of them are wet. They all smell the same. They basically all look like plugs that came out of a car that is running rich. The only plug that looks a little different is the driver side rear plug (when facing the car). That one wasn't as dark colored. It was more of a dark tan.
I pulled off the small vacuum hose on the Fuel Pressure Regulator and no fuel came out.

Now what?

jgcable

Anybody? I was going to replace the FPR to see if that was it until I saw how much it cost! Cheapest I could find locally is $69.00
It looks like a $10.00 part.

jgcable

Replaced the $74.00 FPR, buttoned it all back up. It started right up and ran perfectly smooth. I took it for a ride and about 2 blocks later it started stumbling, missing and hesitating with white oil/gas smelling smoke billowing out of the tail pipe. It is not BHG. I already had that checked. Any suggestions? I guess I will need it towed to the repair shop because I can't figure it out and I need the car.

Fakie J Farkerton

iTrader: (51)

Did you check the pintle caps yet??

jgcable

No, I need to remove the intake to do that. When I checked the plugs none of them were wet or smelling like fuel. I don't think its pintle caps and I will explain. The car did the exact same thing 4 weeks ago. It went from running perfectly for the last 6 years to suddenly hesitating and blowing out a ton of whitish/blue smoke. The first time it happened the next morning it started up and ran perfectly for 4 weeks up until 3 days ago. 3 days ago it did the exact same thing again. It went from running perfectly to hesitating, stumbling and whitish/blue smoke billowing out of the tailpipe.
If it was pintle caps or O rings there is no way they could have repaired themselves 4 weeks ago allowing the car to run perfectly for 4 weeks up until a few days ago.

jgcable

I threw up the white flag and had the car towed to a local repair shop that was recommended to me. They got the car Monday morning. I spoke to them yesterday and they can't figure out what is wrong with it either.
They told me they started it up on Monday when it was dropped off and it was smoking and running like crap. They shut it down and planned on working on it on Tuesday. When they started it on Tuesday it ran perfect with no smoke at all. At this point they don't know what is wrong.
The last repair shop that had it a month ago couldn't figure it out either but it magically started running great and we picked it up and it ran perfect for a month.
I hope this is something that can be sorted out because the car only has 160K on it, it is in beautiful condition, new struts, new battery, new tires, new brakes, new exhaust. It has ice cold air and a BANGING radio in it. Factory sunroof etc... Its a great car. From what I have heard.. 160K is nothing for one of these cars.

njmaxseltd

iTrader: (19)

Just throwing out an idea here. It could be a failing MAF sensor. If it's providing an incorrect reading, say higher air flow, then the ECU could be dumping fuel into the engine causing the issues. See if you can find a used MAF sensor to try out for a while. Somebody on here might have one laying around for ya.

Typically the solder joints fail, you might even be able to fix yours if that's the case. Worth looking into it at least.

Fakie J Farkerton

iTrader: (51)

Has anyone ever fixed a 4th gen MAF?

jgcable

But wouldn't a failing MAF sensor that was bad enough to disable the car throw a code. The motor is throwing no codes.
When this happened a month ago it did throw a code. It was a cylinder misfire. The next morning the battery was dead. It was removed and replaced with a new battery and the code was gone and it has never come back.

DennisMik

iTrader: (2)

the majority of the times the MAF sensor doesn't throw a code. It is an expensive part to swap out on a guess, so if you can get a cheap one from a junkyard, that would be better.

If the engine won't start because the MAF is the problem, unplug the MAF sensor. The car should start but you won't be able to drive it.

When you replaced the battery, having it disconnected from the car reset the check engine light. But since the code didn't come back just makes the problem harder to understand.

jgcable

Not only did the code not come back when this happened a month ago but the car ran perfect for 4 weeks with no issues at all. It ran so good that I decided to treat the car to new struts and exhaust. Then.. suddenly.. with no warning the car did the exact same thing it did a month ago. Maybe the MAF is going. I would think that out of the 2 reputable repair shops that the car has been to at least one of them would have been able to figure it out by now. After all.. there are literally thousands of 4th gen Maxima's driving around town. I am constantly surprised at how many I see every day. When the car was stolen 4 years ago the police told me that black 4th gen maxima's are extremely popular as stolen vehicles because there are tons of them driving around its not easy to identify a stolen one so crooks use them to commit robberies.

jgcable

Also.. to be clear.. the engine does start. Its just randomly smoking out of the tailpipe and hesitating (missing).

DBear

Yep. There's a thread on here somewhere about soldering the connections, and I revived a dead one that way.

Fakie J Farkerton

iTrader: (51)

I opened one up that was bad years ago and it looked good. Heard that didn't happen on 4th gens really. Thanks.