A while back our 2004 started having a slightly rough idle and I'm looking for troubleshooting suggestions as to remedy this.
The car runs just fine but when I first come to a stop I notice the idle gets fairly rough for about a full second or two, then recovers to a slightly rough idle.
If you haven't changed out the intake manifold gasket yet, there is a TSB about it - EG045-07, the new gasket part number is 17171–22060. It's an easy swap and the part usually runs about $5. Get the gasket, a can of QD Electronics Cleaner and a can of Throttle Body Cleaner. Clean the MAF sensor, the IACV and the throttle body, replace the manifold gasket and top it all off by cleaning or replacing the PCV valve. You can do all this in under 2 hours for less than $15.
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If you haven't changed out the intake manifold gasket yet, there is a TSB about it - EG045-07, the new gasket part number is 17171–22060. It's an easy swap and the part usually runs about $5. Get the gasket, a can of QD Electronics Cleaner and a can of Throttle Body Cleaner. Clean the MAF sensor, the IACV and the throttle body, replace the manifold gasket and top it all off by cleaning or replacing the PCV valve. You can do all this in under 2 hours for less than $15.
Okay. I'll clean the sensors and TB today (short on time). If this doesn't remedy the idle I'll do the intake gasket next weekend.
Technically you're supposed to use special Mass Air Flow cleaner spray or Electrical Contact cleaner spray for the MAF sensor but I've cleaned many with Intake Cleaner spray with no ill effects.
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the 5 point is a special tool that I didn't even try to find, I just used my Gerber to grab the sides of the screws and twist them out. As for the gasket - I'm still waiting for mine to come in, so I couldn't tell you what needs to come off. I swear I have seen a DIY writeup on it somewhere. If you look up the TSB it should have step-by-step instructions. I live in Germany so everything takes longer to get to me.
Sometimes a slightly smaller bit will fit "well enough" anyway. It's worth a shot. Otherwise you can slot it with a dremel and use a standard screwdriver on it.
I've had that low idle issue for over a year. Delaer said a 700 rpm idle was ok. Well, it finally kicked off a CEL. Intake mani gasket was the cause. It is common as people have stated.
UPDATE: I replaced the intake gasket today as well as gave a good cleaning to the entire TB assembly including taking apart the Idle Air Controller (IAC), which was pretty darn dirty inside and had quite a bit of resistance in the rotation of the thingy inside that the magnet rotates to adjust the air flow.
Everything is back together but I now have a 1000 RPM idle.
When I first started the engine I threw a CEL and got a code of P0122. I drove around for a few minutes, then cleared the code. It has not yet reappeared.
Any thoughts on why I now have 1000 RPM idle?
Also, when I took apart the IAC and removed the black cover assembly where the connector plugs into, there is some type of what looks like a rotating keyed shaft in there. When I put the IAC back together, it *appeared* that this rotating shaft self-centered itself in the correct position of rotation by effect of the magnet in the cover assembly. Just a point of note that I'm not **positive** that this was correct. It's an assumption.
Um, a little glitch: What type of driver tip do I need to remove the Idle Controller? It's not a Torx or a Phillips. It's some type of 5-star tip - ???
I took my iac to the dealer and asked that same question, and he said it is a tool you cannot buy, and that removing those screws is not necessary to clean the iac. So I left mine as-is.
Quote:
Originally Posted by CMOS
.. had quite a bit of resistance in the rotation of the thingy inside that the magnet rotates to adjust the air flow. Everything is back together but I now have a 1000 RPM idle. When I took apart the IAC and removed the black cover assembly where the connector plugs into, there is some type of what looks like a rotating keyed shaft in there. When I put the IAC back together, it *appeared* that this rotating shaft self-centered itself in the correct position of rotation by effect of the magnet in the cover assembly. Just a point of note that I'm not **positive** that this was correct. It's an assumption. CMOS
Did you remove those 5-point screws to get at this? Not sure what you are referring to. When cleaning my iac I've never moved or rotated anything.
The only time I've gotten a high idle like that is when I forgot to re-plug in the harness after cleaning it.
The wife just went for about a 30 mile trip and the idle seems to have settled down right where it should be. Looks like the PCM was adjusting.
To answer your question - yes I did remove the funky 5-point screws. I used a Dremel tool to slot the screws so I could simply use a regular sized flat blade.
I'll see how it goes over the next few days but right now the idle seems to back to normal.
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