New Here, intermittent idling question, please help!

[mdeeo]

Hi there, I have just bought a Nissan Maxima 5th Gen in Dublin, Ireland, the engine is a 2 litre petrol, model just shows VQ on the rear of boot lid. The car has a full service history with Nissan. There is an auto transmission. The problem I am having is that when I put the car into D or R with my foot on the brake, you can hear the engine pulsing like it is intermittent, unusual feeling for an automatic, it is not like the car wants to get going, you can feel and hear this pulsing.

This becomes much more apparent when the steering wheel has been turned and the you can see the rev counter droppping and rising in line with the pulsing sensation, very strange. If I put the car in park position and do the same it seems fine, no rough idling. Even if I am taking off very slow or reversing very slow and especially when locking steering at the same time, the car makes this pulsing senation feeling. On the Motorways and main roads it is fine when moving along.

I checked the auto transmission fluid and it is all fine. Baffled with this. I brought the car to a local mechanic I know to take a quick look and he said it is just the sterring taking a load from the engine and nothing to worry about. However it is not a very pleasant sensation and this cannot be right. I have had several automatic BMW's and never experienced this sensation. By the way, no warning icons etc are displaying on the dash.

Any help or advice would be great if anyone has a clue what is going on here!

Many thanks and all the best,

Mike.

[tigersharkdude]

From the sound of it it sounds like ignition coils to me. I have 0 experience with the 2.0 though

[goody90q45]

At what RPM are you idling in PARK?
What RPM are you idling in DRIVE with the brake applied?

[mdeeo]

Thanks a lot, idling in Park at around 750 just below the 1000 rpm, in Drive with the foot applied to the brake, the car is idling at about 500 rpm, this is with engine warmed up. It was not doing the pulsing this evening and could not take it for a spin as the other half was heading out.. strange though, it almost happens every time just shortly after it has been started even after driving for a while and it almost pulses like crazy reversing or driving into parking spaces slowly.

It seems more apparent when car is on slight incline when parked, takes a while to happen when it is on a flat surface, well it seems that way! When the pulsing starts, you can hear and feel it, Rev counter keeps going up and down. Not sure if this is related but the fuel economy averages 18.9 to 19.4 mpg, not good with the fuel prices in Ireland. The economy does not change much either on long or short runs, just maybe by a mile! Sorry probably not a great description, hard one to explain.. cannot be how they are though.

Anyway unsure if this could be related.

Thanks again all, Mike.

[the converted]

It's probably your iacv being a little sticky. You can probably clean it out with some carb cleaner and see if it works any better. The FSM stuff for it starts on page 324. This is for the 3 liter, but I can't imagine that the 2 liter is much different.

http://www.nicoclub.com/FSM/maxima/2000/ec.pdf

[goody90q45]

The idle seems close to normal so it rules out where I was going. I'm no expert on your V6 engine but it does sound like a sticky IAC valve that needs cleaning. Just for kicks though, wiggle the MAF connector to see if you can duplicate the problem. Big swings in RPM at idle can sometimes be caused by a bad MAF or a loose/dirty MAF connector.

[loystock]

I'd start with cleaning the MAF sensor and connector; replace air filter, if dirty; and check for air intake leaks then go for IACV cleaning.

[mdeeo]

Thanks all for your help, I'll check this out later and see if I can figure out which is the main problem.
Cheers,
Mike