need help with my 1993 infiniti j30 idling is acting up?

[infinitiboyj30]

when the car is warmed up the car idles very low below 1,000rpm. this happens when i have the car in drive and i apply the brakes and go to a complete stop while im driving. anytime i apply the brakes at a stop the idle goes real low? also when its warmed up and its in park the idle sometimes goes up and then down on its own? i had 2 fuel injectors replaced and the rest cleaned and infiniti said the rest of them were fine and not to change them so i dont know what it can be? and my battery was checked out and was good. i just ordered ngk plugs i was thinking it might need new spark plugs is why its idling so poorly. there are no lights on in the dash so i dont know what it can be....
Modified by infinitiboyj30 at 6:17 PM 2/5/2009

[Infinitiguy19]

It could be a whole slew of things, do you have any more service history?

Off the top of my head it could be:

AAC ValveFuel injectorsFuel pumpAlternatorpossibly more

[infinitiboyj30]

It could be a whole slew of things, do you have any more service history?

Off the top of my head it could be:

AAC ValveFuel injectorsFuel pumpAlternatorpossibly more

i had 2 fuel injectors replaced and the rest cleaned because infiniti told me there fine.i changed all the belts including the timing and water pump.

[Jakw]

Eh, just start cleaning stuff. You getting any codes? When I first got my car, I cleaned the throttle bodies, EGR tubes, MAF, ran some Seafoam, checked for old vacuum hoses, etc. Plugs are a good idea. Air filter, um...the stuff Paul said. Even if none of these are the problem, your car will probably run smoother, and it at least eliminates the possibility.

[Gerardjg]

How low is real low 600 ish is correct with air off, but do clean everything.

[infinitiboyj30]

it idles below 1,000 rpm whenever i go to a full stop thats when the idle goes down. it goes down whenever a put my foot on the brakes and when i let go it goes up barely.

the car exhaust system also has 3 tiny holes in it and i see some smoke commin out of them.

it idles over 2,000 when i go to cold start the car and then when it gets warm it drops to the correct mark but then i go to throw it in reverse or drive and it drops.

[driverdriver]

Your base idle may need to be reset. Very common on J's driven through the winter(especially with major temperature fluctuations). I'm not sure exactly what is involved, but I had the dealer do it a bunch of times for a nominal fee when I use to drive the car year round.

[infinitiboyj30]

i think your right but how do i adjust it myself? should i just tell a shop to adjust the idle on my car?

[Gerardjg]

i think your right but how do i adjust it myself? should i just tell a shop to adjust the idle on my car?

Download the Manual here http://phatg20.net/index.php?o...id=49

EF EC Chapter gives step by step procedures

[Infinitiguy19]

On Q45's and I assume the same for J30's you never need to adjust the idle, when ever you are forced to do so or do so as a temporary/half *** solution it means that the intake tract id dirty and in need of cleaning, which to do a complete job unfortunately involves removing and cleaning by hand each individual piece.

No BG or any other intake cleaner will clean it as well as you can by hand, they are only meant for in between times when the intake isn't badly dirty and extremely easily cleaned.

Seafoam is a temporally solution because there are no cleaning additives just snake oil, read the MSDS for further proof if needed.

[driverdriver]

The way a master infiniti tech explained it to me, even if the intake tract is clean the MAF is working properly up here (In Canada) when it gets cold (and it gets mind numbingly, rubber tires frozen to the pavement cold) windchill and the outside temperature affect the base idle. I couldn't remember if they set it higher or lower. In the summers (we get a lot of off great lake humidity) a similiar thing happens and they have to adjust it again. I remember when I drove the car year around my J had to have an adjustment at least once a year (usually in the dead of winter). My buddies '95 300zx went through the same thing. The Canadian Nissan/Infiniti dealers actually had their own TSB for it.

[infinitiboyj30]

I just replaced my spark plugs and still the same bullsht idle issues so that wasn't the problem! I'm so pissed off at my car and the old plugs I replaced were still good. I noticed when the car is warmed up and I go to stop the idle goes down to sticks under the 1000 mark but when I turn the heat on the idle will go up to almost 1,000 so what can this be?

[J30inthe sun]

I had some problems with my idle fluctuating wildly @ 95 -100,000 miles (97 J30) & it was the Throttle Position Sensor that went bad as well as the Idle Air Control Valve needing cleaning.

See here: zer...light

Good luck!

You may want to have your Idle Air Control Valve cleaned out if you have higher mileage ... say over 90,000.

[infinitiboyj30]

How low is real low 600 ish is correct with air off, but do clean everything.

j30 idles normally like almost right at 1,000 when i have the heat on and its in drive or when its in park. but when i turn off the heat and i got it in drive and my foot on the brake it drops 2 sticks below 1,000? Also it stays below 1,000rpm when I go for a full stop but when its in park it goes up to about 1,000? I changed my spark plugs to oem ngk laser platinum,pcvs,fuel filter and still no help with the idle issues....and my old plugs were still good and the same oem ngk laser platinum is what the mechanic told me so I'm waisting my money here trying to fix this issue so I dunno what more to do

there are no lights on either so i dunno whats wrong with it...

here is a pic of how my idle is when my car is in drive and im holding down the brake now i dont think this is normal:http://i94.photobucket.com/albums/l117/ ... 005992.jpg