unsprung

This morning, I found the car was running extremely rough after a cold start. The car started to sound like it wanted to stall when the RPMs were below 1000 and it kept jumping between 500-800 afterwards while parked. When driven, it seemed fine except when coming from idle at a light and applying only a small amount of gas resulted in studdering again.

When I got home, I ran some Seafoam through the brake booster and there was plenty of white smoke, none too noticible coming from the exhaust manifolds. Because there was a noticeable putt putt coming from the engine, my dad and I then checked the 3 lower spark plugs and the upper left plug and found nothing wrong with the plugs or the wires (couldn't pull the wires on the other 2 so we just skipped them). We then ran some carb cleaner through the PCV valve (after we took it off the manifold) and sprayed plenty of carb cleaner into the IACV while revving the engine. This seemed to help as the RPMs settled when idle and the putt putt died down a bit.

Tonight, after leaving it untouched for 6 hours, I started the car again. The start was a bit rough, acting like it wanted to stall, but it passed. It began at 1500 RPMs and I let it sit for ~5 mins. The idle wasn't as rough as earlier in the morning, but you still felt some of it. In addition, there was white smoke coming from the muffler all throughout and the muffler sounded like it was vibrating / clanking when it was under 1000 RPMs.

So far, my guess is the cylinder's might be causing the white smoke when I start up but the plugs seem fine (haven't checked compression yet). I think the IACV was a bit clogged and the carb cleaner might have loosened up some of the gunk. My tank is running close to E but I don't think the fuel pressure is causing the stalling-like behavior. At this point, the only major thing wrong is my front motor mount has to be replaced and my timing belt & oil are due to be changed. A clogged cat is another possibility as it hasn't been replaced since I've owned the car and the heat shield already fell off. Any idea on what is keeping it from running (especially starting) like normal?

VEvolution

do you feel a performance loss? "putt putt" and shaking muffler are a strong possibility that an injector is no good

unsprung

I'll probably check the resistance of the injectors as well then if those are signs they might be failing. Any other ideas on what else it could be?

Wiking

Time to service u horses. Plugs wires cap - and if only cold: TPS

After that, clean all connectors: 2day job, mind u. Then check the sensors and run selftest.

Find some help & links to hlp here ↓↓↓↓↓↓↓↓

VEvolution

wiking, im having trouble testing the sensors. i dont actually have too much electrical experience. i have a multimeter that can test for ohms,volts, watts.. but whenever i test something(like a penny), i get a million different random readings, and alot of times they drop to zero. what would be a good way to learn how to use this tool? i did some reading on it, but its all so confusing

Wiking

I do agree. For some reason confuzeans have overrun the logic... ohms volts amps. volt x amp =watt

I'll add some to that:

Start from a penny: u should get near zero ohms uSing ohms scale. There are (typically) multiple resitance measurement positions, but testin a penny, all resistance positions should be near zero. (Accurate near zero measurement is for the expensive gauges only). Now try your resistance other edge: moist u finger and see some readings, your skin resistance...(Change resistance scale to get more/less decimal points)

Test the batt in the evening: Voltage scale. One on pos, one on neg. Should be around 12.5V. Next One on pos, another on engine. Should be around 12.46V Next One on pos, another on chassis, strut end nut. Should be around 12.46V (Change voltage scale to get more/less decimal points). If difference is much greater, then your gnd wiring is no good. Put engine running, and repeat. Note: do not use resistnace scale or u blow the multimeter.

Do this in the morning, and u see difference, and may figure out if any system uses power too much -or- batt is bad and cannot hold. Keeping batt terminal off, zooms only on batt.

Nature trip:

Turn to millivolts. Now next take a copper strip, connect it to a clip, place into u mout, near tongue. The other probe on u gold or mercury filling. See how much voltage your batteries produce, and how much mercury and lead, tin inons u swallow daily. Feel dizzy? Go and get plastic fillings like I did...

Ret to maxima:

To figure out how much amps goes during nightwatch: Close all systems but alarm. Take batt pos off. Swap to amps scale, reposition multimeter wires to amp postion and common. Put one on batt, one on batt cable. Now u should be reading amps. Should not be but 0.06 or max 0.1amps. Otherwise there is a malfunctioning device drawing power from the system. U can go 'hunting' by taking fuses one by one, and inserting one gauge lead to each side and see the amount of current flow.

unsprung

Here's a slight update (unfortunately no progress as of yet):

I dropped by the mechanic's a few days ago and he said it COULD be a fuel pump issue. He checked my IACV and found the adjustment screw was all the one down. How it got down that far on it's own, I don't know. Anyways, he set it higher, around the middle, but that hasn't seem to fix anything major. While I was there, I also got my front motor mount changed so I can slowly fix the things that I know need fixing. I also had him pull some codes and everything came back Code 55 (fine).

Right now, this is what I'm looking at:
- on a cold start, it starts up @ 1500 RPMs and when it dips below 1000 RPMs one minute later, it starts to shudder and fluctuate a bit for 10 secs before it jumps back up above 1000 RPMs. It does this about 2-3 times before it evens out a bit and stays below 1000 RPMs with slight studdering.
- it drives without any real noticeable problems until I idle at a light too long, in which it studders a bit. When I start driving again, it feels like there's no power at all.

For now, I'm considering the following as possibilities:
- TPS (connector to it was ripped and two wires on the inside were exposed; I've sinced wrapped the boot in electrical tape)
- clogged cat (a last resort, really)
- oil change (but I don't think it would cause some erratic behavior)
- injectors (though codes didn't say such)
- cone filter (could use a cleaning)
- timing belt tensioner (it's close 70000 miles since it was last changed)

Any ideas?

rawmax1

My car was doing the same thing also. I did an injection flush it ran fine. Then I took car into shop 4 days later to change axle it ran rough and would not start up afterwards. I hate to come on your thread like this but no one answered my thread, and I am kind of lost. At least yours is still running. Since we have the same prob I figure the solution they give you might help me.

Wiking

TPS works only with cold engine and cold engine runs ok =not TPS. After warmup, O2 sensor takes over
- replace O2, measure first

MAF
- replace, measure first

Others, no.

You speak of no connectors cleanup, why? Computers do it all, if the signal is 0,5V amiss because of oxidation, its wonderful if any noise under da hood...
click: http://www.cardomain.com/memberpage/748507/14

unsprung

Wiking:

Your guess is it's an electrical issue? I've been waiting to order a new multimeter for testing but I might just drop by a local electronics store and pick one up to use for now.

Wiking

Buy one 10$ multimeter, then not worried if u lose that. Or a better piece with autorange.

I'd guess 90% problems in maxima are electronics, this or that way. I would start like this if I was unsure:
plugs, wires, cap; clean ECU/TCU connectors, other connectors, groundings. Then test sensors one by one, then self diag. I've tried to explain what I found out on my web pages.

LMaRiE91MaXiMa

question: i heard white smoke ALMOST always signifies a blown/cracked gasket...is this true?

Wiking

Steam is white. Cooling liquid leaks could produce steam; head or intake seals. Then the coolAnt level drops gradually; rough idle no.