So long story short, I was leaving the bank a little while ago and when I started my car there was a really REALLY rough idle upon startup. It was so rough I could feel the engine shaking and idle was so low I almost thought the car was going to stall. I turned the ignition off and started again and it did the same thing. I thought to myself wtf, and backed out of my spot and started driving. I stopped for a second and idle was normal, as it was the rest of the way to my destination. I stopped at the mall on the way home and the car started and idled perfectly fine and havent had any sign of the rough idle again........ yet... Anybody have any ideas what is causing this, and how I can fix it. When this occurred I was parked on a slope with the front of thcar facing uphill, also there is no cel currently on. I knida think it might have something to do with my rear engine mount

 

How long has it been since your last tune-up ? Sometimes a dirty fuel system, air cleaner, spark plugs, etc.........can cause problems. Try some fuel system cleaner in the tank, clean EGR passageways and intake, replace plugs with NGK's, replace air filter, check all vac lines for leaks, and finally look under the "DIY" section for other tips.

There could be a coil or injector on the edge. It's best to eliminate the simple stuff first.

 

Hmmm...it's fall, that time of year again when these damn additives are put in gasoline. It could be the winter gas causing this issue as you described.

 

thats not winter gas!!

get the codes ckd even though no light of CEL,,just in case

first thought is clogged egr system,,have you removed the intake manifold and done that service yet? needed every 75kmiles

age of plugs? correct ngk if recently installed?

but the description matches several clogged egr port and passage symptoms

what year and mileage?

 

Sounds like some Intake Manifold and IACV Wants Cleaning... Best Tune-Up I ever did to My Car.

 

Have not removed intake to do egr cleaning yet. Will this cause engine damage if clogged?
Not sure of the age/condition or brand of plugs installed, havent checked since I bought the car.
Its a 2000 and currently has 196,000 miles, I purchased it back in March with 182,000. Havent had to do much to it besides rear brakes, front wheel bearings, oil changes, and a 3x3 with dw-1. I did recently clean the tb tho

 

I had an issue like that about 2 months ago, turned out to be a bad sensor. IAC sensor I believe. Reads the temp of the air coming into the engine. Works with oxygen & gas mixture. Located in back of intake manifold. Cost me $30 & 5min to change it.

 

Hey Jra8858, considering the mileage and not knowing the previous owner's PM, you have nothing to lose by performing a basic tune-up, along with new NGK plugs. The EGR passageways definitely should be checked as they really do get "gunked up" and can cause idling problems.

Do the simple stuff and go from there !

 

Dirty EGR ports was the first thing that came to my mind upon reading the first post.

 

Ok I will start with performing the egr cleaning procedure and take it from there. It seems as though most people say clogged egr/tuneup, or dirty/faulty iacv so thats where I will start. When I have some free time to work on it I will report back with my findings.

 

here is the cool part- its a crossover labor job!
remove intake manifold for egr cleaning- TB is attached to it
remove TB and flip over- there is the IACV cover-
its a rod with an air slit that rotates as needed = constantly adjusting micro airflow for idle
remove rod and clean slit- also clean where it works,

clean air plate on both sides and edges

 

For the Record you will need like 5 Bottles of Carb Cleaner to Leave the Manifold Spotless... Buy the Autozone Branded works very good and it wont leave a hole in your pocket.

If I recall is like 1 Bottle for TB and IACV
and 4 Bottles for EGR Passage and Manifold Overall.

 

wow yours was clogged!!,,most get by with 3 cans for intake manifold
doesnt need to be spotless
as soon as you start the car the crud process begins

tb air plate, use carb cleaner and old toothbrush if needed,,that you want clean as possible
open throttle to get rear side of air plate, and its edges all around the diameter

 

I did all that becouse I think the Autozone stuff isnt that Abrasive so I had to use a Little More Anyway they had this special like 3x1 so I bought 6 hahaha I have 1 laying around the Garage..

I basically dissasembled the Type-S manifold in all its 3 pieces and Leaved everything looked like it was New... The EGR Passages was very simple and fast to clean it only had like this Crust on them I tought they were Clogged but It was Actually the Crust that attaches into the Upper Manifold Cover Gasket so they werent clogged at all.. But the EGR Plenum (Where the EGR Port Starts to Widen in the Manifold) Was Hilariously full of Crust It actually tooked a full Can and alot of Brushing to leave it fully clean...

 

Hi, I figured I should update everybody on my situation. Well turns out I was a little low on coolant. Filled her up to proper level and not have had any more rough idling at all for over a month!!

 

Where is the iacv exactly located?

 

On the bottom of the Throttle Body.