I think this can probably be solved pretty quickly since I have noticed a lot of smart people on here.

My friend has a 90 Maxima with a VG30E with 170000 on the clock

Is misses very consistantly at an idle like every half second.

At first I thought it was the fuel pump since I can sqeeze the fuel line nearly shut with 2 fingers in front of the filter.
But I am starting to wonder wither thats it at all now because it could be so may things.

I told him to take it on the highway and stomp on it. He said it missed for a sec then it accelerated nicely.

It is a very consistant miss hot or cold and the weather doesn't change it.

Thanks in advance guys
andy

 

Same thing applies here.

Things to do and try with SOHC engine:
- Check timing
- Change distributor cap/rotor/spark plugs/wires
- Use 91 or better octane gas
- Run fuel injector cleaner with every oil change
- Ohm check injectors
- Change air/fuel filter (since you are doing all of this)
- Clean throttle body and AAICV
- Check ECU for codes
- Replace PCV valve
- Inspect (and replace if necessary) vacumn hoses

Any of these things will cause your problems. Fix all of them, and you will be in the clear.

Good luck and keep us posted.

 

One quick way to see which cylinder is missing is to pull plug wires one at a time and see if the idle changes at all. If you find one that doesn't affect the idle, chances are that cylinder isn't firing. Just helps to narrow down the problem. Goes in line with what DARHAW said about injector ohming...this way you may only have to check the one, instead of all 6. All of those things he said are good maintenance type items to check or do on a regular basis. Besides, he has an excellent looking max, so he must know what he's talking about...

 

Thanks broncoguy.

 

Thanx for the quick replys guys I will try to do all these things

 

I still have not received my service manual but would like to know more about ohming the injectors. How is this done, what reading should I see? Also cleaning throttle body and AAICV, how, where with what? I figure these are easy & cheap to do before I start replacing parts randomly. Mine was missing pretty good at fast idle this morning when I first started it. Filled tank for second time, put in techtron injector cleaner, checked gas mileage, she came in @ 28 mpg mostly highway, I like that!

 

I wouldn't bother ohming them unless you have some indication that you have a problem. It's not hard, just not necessary to do on a regular basis.
But, if you need to, just remove the connector and put one probe on each contact. Correct reading is between 10-14 ohms. Anything outside that, and your injector is headed for trouble. Be careful removing the connectors, since the plastic gets brittle with heat and age. Also make sure you remove the little retaining clip before you pull on the connector. The clip looks like a large staple, and slides out easily with needle nose pliers.

Again, I wouldn't mess with it unless you need to.

 

As for the aforementioned things to replace, the price of all of those items combined should not exceed $120.00. Again, you really don't need to all at the same time either. One of the things that you really want to check is the distributor cap and rotor. Although it is a high-tech engine, the SOHC still uses the tried-and-true distributor based ingintion. Since this is a highly overlooked item, it is very possible your distributor contacts are pitted. Price for new cap and rotor: $36.00 from Autozone. Actually, the most expensive item on the list are the spark plug wires. If you check them with an ohm meter and neither wire reads highter than 20K ohms, you won't have to replace the wires.