Hey Maxi heads,

Quick Rundown: 182-187 PSI compression, no overheating, smoke is not blue, car runs good

Where do I begin... I bought a 'non running' Maxima last year. It has been a lot of work, but I'm at the point where it drives (I replaced timing kit, waterpump, front 3 fuel injectors, evap equipment, evap canister, knock sensor, and put new spark plugs in it)

Now that I've solved the last evap code (evap canister stuffed + vent valve stuck), it seems to have all of its power back. Weird, I know - this shouldn't cause a power loss, but the knock code would. I have been casually driving it on and off to fix the emissions codes. It still has knock code P0325... However, this is also the first time I've had a working battery in it and it has seen several days of start cycles logged into the ECU. It had an overnight battery drain before, and I would drive it one day then not touch it for a week. Every time it sat it was to the point where the alarm would go off when I jumped the vehicle. Pretty sure it never did any kind of learning procedure. Maybe that's what I can tribute to having the power back...


I have changed oil several times since chain job because of the amount of shredded material in the oil pan. I run TCW-3 in the gasoline (Premium). MMOA in the oil (Trying to flush her... the EVAP canister was 100% full of charcoal! It had been driven like that for a while, judging by the electrical tape that's over the CEL)


Anyway, now that it's running correctly, I flogged her a couple times. Plume of smoke. It's bad. Smells like rich gas. It is NOT black/blue. It's white-ish. Compression test revealed 182-187PSI in each cylinder. No overheating.

Could the rear 3 fuel injectors be leaking bad enough to cause a plume of smoke on acceleration? I would think that it would smoke at all times with unregulated fuel getting into the cylinder.

Another thing, rear spark plug wells leak oil. I removed the old plugs to judge signs of wear. None of them revealed an oil burning situation, but it was hard to tell with that amount of oil that poured all over the plug. I don't think this could cause plumes of smoke on acceleration... you would have extra oil in the cylinder when you change your plugs and it may cause spark to jump, causing other issues...

I would assume oil rings in the cylinder if it were blue and/or oily smelling. I have owned/seen/repaired blown oil rings before (Well, stuck and broken oil rings). This doesn't seem to be it.

Any help guys? I was almost at the finish line, and now the fog's rollin' in

 

My only guess would be a small fuel leak. Could be that the lower o-ring is slightly pinched so when you accelerate the fuel pressure allows the fuel to push past the o-ring. Or the pintle cap could be functioning wrong. Hope this somehow helps.

 

White smoke that smells like gas is unburned fuel. I've been there, three years ago. Refurbishing my injectors solved that problem. Unfortunately, too much fuel had been going on for a while and the cats became cooked and clogged. So the money I saved by refurbishing my own injectors helped to pay for a Warpspeed Y-pipe so I could delete the cooked and clogged cats. Now it runs like a screaming banshee.

Also check the fuel pressure regulator if you haven't already.

 

Based on the symptoms you've described, I'm inclined as well to say "bad injector".

I'll go so far as to also say that the likelihood that it's #5 is high.

 

Thank you all for the input!

I was discouraged for a moment. Off with the intake! I will replace those injectors and replace the valve cover gaskets... Lets see if its #5!

 

I say it's a bad injector. Probably one of the rear ones. I would remove all three rear plugs. one of them might smell gassy, or appear wet.

Be sure to replace all the rubber fuel hoses while you are in there any way.

The egr pipe is also more accessable once the uim is off. As is the knock sensor. Also the heater hoses. Use the opportunity to make repairs and preventative maintenance when the uim is off.

 

In the middle of this exact process. word of advice be careful with the valve cover bolts, i torqued to spec and still broke the first 2. i am glad for this delay though because i decided to do a full tune up while i have it apart, spark plugs, ks, injectors

 

Sorry to hear Violator! That's tough luck. What are you doing in there?

I ordered my UIM/VC gasket kit last year... time to use it.

I'll service everything you guys have mentioned. Then to do the emissions-ready drive cycle.

 

Valve cover leaks, it ruined my alternator and after putting in a new one it's time to fix these oil leaks I don't wanna replace another alternator. I also have nwp spacers and it's nice to have an excuse to paint the valve cover and uim, and a midlife refresh on everything else while I got it apart would be nice. I've actually heard good things about the eBay injectors so I bought a set for $55, even if one fails in the long run I could replace it 10times over before it costs as much as the oem

 

Bummer! My VQ was sludge mountain before I tore it apart for timing chain service... (I didn't do the cam chains/tensioners, so VC's did not come off. Worked well)

What are NWP spacers?

I bought these fuel injectors

They were on sale for $42 or so... but half of them wouldn't fire! They had different colored pintles, different colored o-rings... kind of mix and match. Luckily CS_AR is sending me some fuel injectors to use! What a guy!

I wish we could run the plastic engine covers found on the 2000+ Maximas (I think those are the years...)

 

We can swap the whole 3.5 vq35 in with the cover if you really want. nwp spacers are performance gaskets for the intake manifold. They cool air intake by up to 40degrees by blocking heat transfer from the exhaust manifolds to your intake, giving some good low to mid range power along with the fact they eliminate the need for gaskets. The gain has been dynoed to around 10hp, almost as much as a ypipe but it doesn't take away from low end power.