Hesitations and Stalls

[Hollowbelly15]

My 99 Maxima has been through alot already and I've had numerous issues before that I've tried to take care of. It seems that every time I fix something, another part fails.

Anyways, this time the issues are getting worse and worse so here they are:

-When the engine is cold, it stalls when I shift into reverse
-Occasionally the engine will stall as I slow down to make a turn/approach a red light or stop sign
-When idling, there's a shudder or hiccup
-Occasionally when cruising at highway speeds, there's a big hesitation and the car lurches and then returns to normal

So that's the big stuff. I pulled the codes and got these: P0100 - MAF or VAF: circuit malfunction and P1320 - Intermittent misfires

Recent work includes new plugs I put in, cleaning my K&N air filter which had gunked up my entire intake, and cleaning the MAF and throttle body.

Any help would be greatly appreciated, I'm a college student and really need the car to operate.

Thanks

[loystock]

P0100 is a hard fault and cleaning the MAF sensor will not fix it. You have to replace it. A refurbished one may fit your budget. As for the P1320 it could be the ignition coil, condenser (capacitor), harness, etc. You can do a basic power balance test (disconnect one ignition coil/plug at a time and listen for engine response. You may need a new coil and swap it one at a time until the problem is identified. There are numerous threads about this issue and I have done several write-ups. Do a SEARCH.

[Hollowbelly15]

Stupid MAF, what of those symptoms will replacing it fix? Anything in particular?

Also, thanks for the info on the other code, I'll see if I can do that soon.

[loystock]

The problems you are seeing maybe related to MAF sensor and/or misfire. A defective MAF sensor may also cause the engine to run in 'limp mode' (speed limited to <3000 RPM). So replace the MAF sensor and go from there. If you're lucky, the misfire may even go away.

[Hollowbelly15]

Do you know of any specific place I can find a refurbushed MAF sensor? I've been looking but I don't know what sites are reputable.

[loystock]

NAPA or if you want to go on-line, Rock Auto. The price is @ half of a new OEM sensor.

[Hollowbelly15]

So I got my new sensor in the mail today and installed it.

I started the car and shifted into reverse while the engine was cold and the car didn't stall (good sign). It didn't do that all the time with the old sensor so it'll take a couple of days to make sure that issue has been fixed.

I am going to start testing for the misfires now, thanks a lot for all the help. My family needs the car to use after my dad's '01 Max got totalled by some s*** so it'll be nice to have a good working car.

[loystock]

I'm glad to hear that. Please let us if you need additional help.

[Hollowbelly15]

So the stalling problems are gone thank goodness. I still have the shudders at idle, though. Could that have anything to do with a too-low idle speed or would that be caused only by a bad cylinder?

I searched for how to do a power balance test and only found other references to it, do you have a direct link to how to do it?

[loystock]

A basic power balance test involves disabling one cylinder at a time (disconnecting coil/plug/injector) and observing the engine's response (if no change - bad cylinder component like plug. coil or injector; if engine seems to stall or stutter, the cylinder is good). The dealership has more sophisticated equipment to detect even subtle changes in engine response.

Here is one thread on P1320 issue - post5326944.html?hilit=p1320#p5326944