G3Karl

iTrader: (1)

my 92 gxe will either want to idle ~1500 rpms in neutral/park or ~800 in neutral/park. Anyone know whats going on? Seems like there is some sort of "something" that is making it switch between these two points. And by the way, it does not hunt up and down between 800 to 1500 rpms. It will hold steady at one or the other.

LvR

Irrespective of temperature? - Clean IACV and see if it sort the problem

burhan92SE

clean ur MAF with maf cleaner.

internetautomar

iTrader: (30)

1500 should be when the engine is cold
800 should be when it is at operating temperature.
There is no middle really.

G3Karl

iTrader: (1)

O.K. I did not mention that this happens regardless of engine temp. When the car is fully warmed up and driven for awhile I can pop it in neutral/park and it will idle ~1500 rpms then eventually drop to 800 rpms after a minute or two. No hunting at all. I will swap the maf and see what happens. I have a spare one on there now and will put the original back on.

G3Karl

iTrader: (1)

temp does not matter. I will swap the maf first then if that does not work clean the iac valve.

maximaman1313

check your throttle position sensor harness...

My car will idle 1500 when its fully warmed up, and if i wiggle the harness it gets back to normal. I fixed it since, but a bad connection on the TPS will cause this problem. The rubber piece on the harness by this time in the cars age is cracked and broken off and corrosion sets in on the wires inside the harness and become green... pull the harness of the TPS and clean it good with electronic contact cleaner and a small wire brush. I would also take a small nail or needle and bend the pins inside the harness so when you reconnect it to the TPS it makes better contact.

maximaman1313

ya because its steady at 1500 or 800, i say bad tps connection.

like others said, clean the IACV, but honestly I would think that it would give more of a fluctuating idle than an idle thats either 1500 or 800...so I got my money on the tps harness connector

fattamax

where is the TPS harness because I have a condition like this as well. My idle is around 500 and the car almost bogs down, but when I am in neutral or park the RPMs are like 1500.

burhan92SE

check the codes first guys if there is any, before jus swapping out stuff...

infinitiblast

iTrader: (2)

So I will join in on this discussion, my car has started doing the same thing..but I am 5SPD. When I come to a stop the car takes forever to come back to normal idle...it did this for a few days. Then it started having fluctuating idle up, and down same as the OP regardless of Temp of the car.

I have done the following.
1. Replaced the IACV with a known good unit
2. Checked, and replaced any cracked vacuum lines
3. Cleaned the MAF with cleaner.

Now my car when you start it be it cold or hot, both fans kick on automatically and the car idles at a minimum of 1500, if I unplug the IACV it goes higher...and the IACV screw does nothing to lessen the idle I can close it all the way down...and it will still idle at 1500.
I am starting to think its my temp sensor....but I dont know? I am getting no codes....

Greeny

iTrader: (43)

^^^^
Yep, coolant temp sensor, or more then likely corrosion and/or a loose connection at the cts.

infinitiblast

iTrader: (2)

^^^ Do you think this was affecting my idle before as well?

Greeny

iTrader: (43)

It's possiboo..

maxitech

iTrader: (7)

maxinout93

Every time I unplug my tps it is full of green stuff. I will get some electronic cleaner and see if it helps out when I clean it again.

maximaman1313

need something solid but small enough to try to scrape some of that green crap out...

I ended up rebuilding a JY harness and spliced it onto mine.

That green stuff is bad, and kind of hard to completely get rid of. get what you can out, and put a lil bit of contact grease to help prevent more corrosion and make a better contact.