Idle Issues - Tune Up Attempt FAIL

[SLCE30318is]

So I managed to turn what I'm sure is a simple routine maintenance into a screw up.

The car ran fine for 2000 or so miles prior to me trying to do a tune up on the vehicle.

I tried following this guide to cleaning the throttle body and intake manifold.

http://forums.bimmerforums.com/forum/showthread.php?454501-Idle-Control-Valve-Write-up-ICV-clean-DIY

It looked different and I got to the point where I decided not to take off the intake manifold and just cleaned up the throttle body and ICV. I put the ICV back to where I thought it was supposed to go, and reconnected all of the hoses (after much squirming around back there to get it to fit back in).

Now it's idling erratically, I can smell gas in the exhaust, and the check engine light comes on.

I checked with some topics on here, and I suspect I may have a leak in one of the old hoses? Before I go out and buy new hoses, I want to make sure that I didn't just incorrectly reinstall the ICV.

Did I put this ICV back correctly?







Also, is there supposed to be something connecting to the this hole at the bottom of the tube going from the MAF sensor to the throttle body?

[deansweet]

What part of the country do you live in?
Maybe one of us could stop by and help you sort out where your leak is?
The ICV looks like it's insalled right. So that's the only thing you removed? The ICV and the hoses coming in and out of it?

[SLCE30318is]

I live in Houston, TX.

I only removed the throttle body and ICV, along with the hoses.

Thanks,

Ian

[deansweet]

That last picture where you have an unplugged 90-degree angle is supposed to go to the IAC unit on backside of block?
Where do you have that hose connected now? If you have done the mess under the intake delete then that hose can go directly from bottom of IAC to that plug you pointed out. Not too sure where you have that hose going now? If you have it going to the other port on bottom of intake body then you can siimply plug the other hole and it might help your poor idle. Problem is as I see it you have a massive leak with that open 90-degree elbow.

And if yuo are still using all the original PVC and coolant lines under the intake... when you started pulling them to do your maintenance ou may have cracked them? Mine were falling apart rather badly. I bought all new hoses for the 318is and the replacement collector that both the coolant and vacuum lines run thru under the intake failed after 6months so I completed the 'mess under the intake' delete and all is well thus far.

Hope this helps.

[SLCE30318is]

So I have the hose coming from the ICV going to the 90 degree hole that's closest to the throttle body.



I tried to plug it into that second 90 degree hole, but the hose doesn't reach that far. I don't remember if I had disconnected any other hose to that second hole (closer to MAF). I don't see any unplugged hoses left either.



Appreciate the help,

Ian

[keflaman]

There should be a plug (and it looks like there is) in the second hole. Look up "stomp test" and see if you can get the trouble code for your check engine light.

Don't be too hard on yourself. Like Dean said, there's all sorts of things ready to go wrong simply because of age and deterioration. If you plan on doing all the work yourself, you'll be intimately familiar with the car in a year or two.

[SLCE30318is]

Getting a 1222 code.

I'll look into getting mess under intake done to it. Looks like the next step is to just replace the hoses for now?

[SkidMark]

1222 is rich/lean code.. vac leak..   Skid

[Tgoode318]

I can see in one of the pictures of your intake hose looks Cracked I bet you that is why. Often times when you do work on these cars just taking the hose's off to do what ever your going to do can be the final straw that puts them over the edge and cracks them.  On our cars they are very brittle with age usually. A cheap way to check for vac leaks is to spray carb cleaner around your engine bay with the car on and listen for a surge in idle. When you find this surge you have found your Leak.  Usually by the time you are seeing 1222 you will have multiple leaks.

[SLCE30318is]

Hm I think you're right. As I was twisting and tightening it, I noticed it cracking all of the place. The carb cleaner test revealed that the leak is probably coming from the end that connects to the throttle body. I didn't get a surge in idle when spraying the hoses that I was messing with earlier, but I'll replace those anyways when the new intake boot comes in.

Thanks for the help everyone. Hopefully this gets resolved soon.

[DesktopDave]

1222 is a catch-all error code. Could be a lot of issues, but a vac leak is very likely.

I also see mild cracking in your throttle boot around the AFM and between a few pleats. A new boot is an excellent idea. I'd presume you need a few new hoses in there as well.

Mine has a plug under the throttle boot as well; I swapped it to the upstream hole when I did the hose mod and replaced everything with silicon rubber. Be aware that the ICV cannot connect to the spigot under the TB...that goes to the cyl head cover. The ICV hose must bypass the TB to function properly.

Those ICV hoses under the manifold are notorious for leaking, and an M42 was never known as the smoothest-idling engine.

[SLCE30318is]

So I replaced the ICV hoses today and tried it out. The idle started out the same, but after a few minutes it stopped surging up and down. It stays pretty steady at around 700 rpm but it still idles really rough and I can smell a lot of gas in the exhaust fumes.

There's no more check engine light, and the stomp test reveals 1444.

I also tried disconnecting the neg. battery terminal for a minute to see if I just needed to also reset the thing. It still idles really rough and burns rich.

The new intake boot should arrive tomorrow or Monday, I'll see if that fixes it once and for all.

[SkidMark]

1444 no codes... this is good!

[Tgoode318]

Like i said hopefully its just Multiple sources of failure in your hoses. The Ideal setting for an internal combustion engine is stoichiometric; Ie  one gram of fuel, 15 grams of air are required Any mixture greater than ~15 to 1 is considered a lean mixture; any less than ~15 to 1 is a Rich mixture (i.e exhaust smells excessively of gas or "rich". So as you can see small disruptions in the air intake can lead to quite drastic changes in this formula which means a rough running engine. The Dme for this time period is incredible sophisticated in the fact that it can adjust for these measurements in order to accommodate for small failures;  How ever after a certain percentage of disruption the dme can no longer compensate and will throw a CEL (check engine light). It sounds like you were able to fix your leaks enough that the Computer is able to mange the remaining leaks but it still wont be 100%. Hopefully Your new intake bellow Should Be the last piece of the puzzle! GL!!
-TG

[SLCE30318is]

Thanks for the suggestions and explanations guys, I really appreciate the support as I'm learning this thing.