Need some SEARCH ideas for my crappy idle.

[siceclipse]

As the title says:

I been having really crappy idle problems lately. The problem is intermitent and just happens some of the time.

When I start the car it turns over and the RPMs go up to 1000 and then the car wants to die like its on 2 cylinders slowly making its way up to 3 cylinders and then when it sounds like its running on all 4 the ilde will go back to 1000 for about 5 sec and then down to 750 and stay there for the rest of the time im driving (when i come to a stop that is).

please give me some search ideas.

I have:

New Battery (on car)
New Alt from Mitsu. (on car)
I have a spare coil pack laying around (my car IS a 95 so its old as hell)
and i have a spare TB with all sensors in the garage somewhere.

thank you

Sorry!!

I forgot to add
I have semi new plugs in there and brand new MSD wires
and Bruce, yes i did i boost leak test.

 

[ndsti]

Check your IAC, it should read between 28-33 Ohms at ambient temp. Test the pins in this order; There are six pins on the ISC. They are labeled 1 2 3 across the top and 4 5 6 across the bottom. Measure the Resistance between pin's 1-2, 2-3, 4-5, and 5-6 Each pair of pins measured should read 28-33 Ohms Note: The values should measured with the car off and cool! If any of the "coils" (which is what you're testing) are bad then your ISC needs to be replaced. Commom problem with idle issues!

 

[Gromit]

As the title says:

I been having really crappy idle problems lately. The problem is intermitent and just happens some of the time.

When I start the car it turns over and the RPMs go up to 1000 and then the car wants to die like its on 2 cylinders slowly making its way up to 3 cylinders and then when it sounds like its running on all 4 the ilde will go back to 1000 for about 5 sec and then down to 750 and stay there for the rest of the time im driving (when i come to a stop that is).

please give me some search ideas.

I have:

New Battery (on car)
New Alt from Mitsu. (on car)
I have a spare coil pack laying around (my car IS a 95 so its old as hell)
and i have a spare TB with all sensors in the garage somewhere.

thank you

Sorry!!

I forgot to add
I have semi new plugs in there and brand new MSD wires
and Bruce, yes i did i boost leak test.

Based on what you describe, I think the 1st place I would search for is posts that talk about bad FIAV - Fast Idle Air Valve. On cold starts, the FIAV is primarily responsible for controlling the idle (although the ISC is active to some degree) & will keep it between 1k - 1.5k until the vehicle has warmed up. Then it drops to the normal range of 750 rpm +/-50 rpm & the ISC is the primary control.

Other idle control problems can be casued by a bad ISC, bad EGR valve, & bad engine coolant temperature sensor, to name a few.

There's a very big write-up in the VFAQ that talks about a whole bunch of idle control possibilities, although the topic title points toward idle surge.

Happy searching!

 

[andymoraitis]

If the motor does it when warm, I'd look into a leaking BISS o-ring or the ISC as mentioned above. Typically, the ISC will take over control from the FIAV once water temp reaches 122 degrees.

Keep us posted,

Andy

 

[siceclipse]

Andy,
I know for a fact i have a small leak at the O-Ring
i do have that second IAC to go in.

And to the above posts, this is mostly a "hot start" problem but its so intermitent that its hard to tell.
Also it is not "surge", its like the motor wants to die (sounds like a subaru) and i have to wait for it to come back to life (takes about 20 sec total)

thanks again for the help and remember im looking for terms i can plug into the Search
But ill take any advice i can get at the same time too.

thanks again.

 

[andymoraitis]

If you have a BISS o-ring leak, fix it and re-set the idle. I'd aso test the ISC as mentioned above and see if it's working. If not, the guys at http://throttlebodys.com have replacement ISC's on the cheap.

Fixing the known issues will make it easier to diagnose the issue and get ir resolved.

 

[siceclipse]

ok, im going with something on the throttle body.
Today before work i started the car and it went to 700 and then died.
tried it again and it struggled to stay alive a little longer but still died.
started it up a third time and it struggled for about a min before it went to normal 750rpm