Any tips on cleaning EGR and IAC? - Toyota Nation Forum : Toyota Car and Truck Forums

badappex · 10-11-2007, 05:14 PM

I've got the common symptom of driving on the highway 40+ miles then as I reach a stop, the car starts to sputter as RPMs dip to 500 or so. Car doesn't have a check engine light or anything but reading similar posts on this forum it seems I should clean out the egr and possibly the idle air contr. Any tips on removal, cleaning and what to look out for from someone who has done this?

The car is a 99 I4 with 66k.
Thanks.

hooRAH · 10-11-2007, 05:47 PM

Its fairly easy.

I get tired of trying to disconnect the coolant lines that run through the throttle body, so what I ususally do is I unbolt the throttle body but leave the lines connected. It lets me move the TB just enough to be able to get at the back side with a rag.

Make sure you get all the small vacuum ports on it. I don't usually take the IAC motor off, I just spray some cleaner into the passages through the TB, let it sit, and then blow it out with compressed air later.

For the EGR, just remove the valve, spray some carb cleaner in it, and blow it out with compressed air.

While you're at it, you can check the EGR modulator for holding vacuum. Good luck!

badappex · 10-11-2007, 06:21 PM

Thanks.

When you say remove the egr valve, does that include the metal line running into the block? it seems some 10mm nuts facing downwards, are holding the valve.

hooRAH · 10-11-2007, 06:34 PM

yeah there should only be 2 of them holding on the valve. The metal tube is part of the valve.

badappex · 10-12-2007, 11:35 AM

So i do need to clean out the metal portion of the valve? Or is the main concern with the valve itself?

Sorry for the multiple questions but I did a search and only found vague instructions on this.

greggf · 10-12-2007, 12:59 PM

For the IAC sometimes it helps to connect and disconnect the IAC wire connector repetitively while spraying carb cleaner into the IAC port (small hole before the throttle plate). This is done with the engine running. This allows the valve to open and close for better cleaning.

moocow · 10-13-2007, 02:25 PM

Would a dirty EGR also cause rough idle on starting the engine, also happens more frequently on cold starts, tends to idle rough and low RPM's for a few seconds then the engine just dies. I have to hold down the pedal to keep it alive until the engine is warmed up.

greggf · 10-13-2007, 03:34 PM

Quote:

Originally Posted by moocow

Would a dirty EGR also cause rough idle on starting the engine, also happens more frequently on cold starts, tends to idle rough and low RPM's for a few seconds then the engine just dies. I have to hold down the pedal to keep it alive until the engine is warmed up.

That is typically IAC valve gunked up.

moocow · 10-13-2007, 07:33 PM

Can you give me any pointers on where it is exactly, and how to clean it out? I am looking in my service manual but its not showing the specifics, I have a general idea where it is and what it looks like but I can't be sure unless I can confirm it from anyone here.

moocow · 10-14-2007, 03:09 PM

ANyone?

moocow · 10-14-2007, 08:03 PM

Ok I located the part, so I undid the black hose from the airbox, and unscrewed the three bolts that held it on the throttle body. I used some engine degreaser to clean it out since I had no throttle body cleaner but it worked just as good. I didn't spray it in the throttle body, just the part where the cable pulls the lever to open up the airway... whatever its called - the circular shaped brass colored thingy. I started the car and no weak idle anymore.

I didn't clean all of it though, I don't have an air compressor to really spray down the square holes and stuff...

badappex · 10-18-2007, 12:18 PM

Sounds like it did the trick. I cleaned out my egr valve and connecting rubber hoses. I left the lower metal line running to the back of the block because I couldn't see a a away to grab with a wrench. Car still stumbles after a long drive at idle.

I will try to clean out the IAC a little better and see if that helps.

Any other reason why the car stumbles? Spark plugs, vlaves, timing?

1996camry · 10-18-2007, 12:40 PM

96 camry le 4 cylinder le 5sfe engine..has the same problem like u...cleaned out egr and the idle helps..but still feel a little rough idle when i am doing a long drive (stop at dead stop) ...rough idle ocure..but cold start doesn't see rough idle but when the engine get normal hot temp gauge...it starts feel rough idle....

i haven 't clean my IAC yet but i'll do in the next two weeks..to see the rough idle go away..keep posted if u cleaned IAC helps rough idle on your car... i think a lot of people have the same problem rough idle..

moocow · 10-18-2007, 04:51 PM

Oh nevermind, the idle problem came back today, guess I gotta take the whole IAC out and clean it out real good. Its kinda tough to get it out, with the two bottom hoses at the bottom, I can't seem to slip flat pliers in there to undo the clamps.

ekopel · 10-18-2007, 05:33 PM

I know i need to clean my IAC...but I am relectunt to take it apart at the moment cuz im not that familiar with it. If someone did a write up (maybe pics?) It would be very appreciated! P.S. anyone know if there is a writeup on these forums for 1mz valve cover seal replacement? or is it just that easy?