idle is around 1500, anyone else?

[bmw_pwr]

hello guys, i just bought 318ti today, first bimmer, was verry happy, but cus im a student, i dont have too much money, so i bought a as is so i can fix myself, so here it goes, i start the car, the idling is fine, 800.. and when the car gets hot, it goes to 1500, and drops to 1200, goes to 1500 and drops to 1200.. and it gets anoying as im in the lights, and the car is idling already high, and it dropps, revs and it drops, any ideas what that can be???

[xxxJohnBoyxxx]

Originally Posted by bmw_pwr

hello guys, i just bought 318ti today, first bimmer, was verry happy, but cus im a student, i dont have too much money, so i bought a as is so i can fix myself, so here it goes, i start the car, the idling is fine, 800.. and when the car gets hot, it goes to 1500, and drops to 1200, goes to 1500 and drops to 1200.. and it gets anoying as im in the lights, and the car is idling already high, and it dropps, revs and it drops, any ideas what that can be???

That is called a hunting idle. The first thing is check for vacuum leaks or a cracked intake boot from your MAF (Mass Air Flow) Sensor to the throttle body. You will most likely find a leak that needs to be fixed. If there are no leaks then next I would clean your ICV (Idle Control Valve) which might be causing your car to hunt for the correct idle. It needs to be removed and cleaned with throttle body cleaner and a Q-tip. Once that is cleaned well re-install it and you should be good.

If these two items are not the issue then we will need to dig deeper and look for another issue that could be much harder to find.

Good luck, John S

[cooljess76]

+1 what John said. You can check for leaks by spraying brake/parts cleaner on and around the intake boot and all of the vaccum hoses while the car is idleing. Soak that intake boot really good, try to get up underneath it as well. If you hear the car rev up, you've found your leak. Save a little brake cleaner just in case you don't find a leak, then like John said, remove the ICV and give it a thorough cleaning. The two other things that I'd check if the brake cleaner trick doesn't work are the CCV(crank case vent valve and the actual port towards the back of the valve cover where the hose attaches. These two things are known to get clogged over time and cause idle problems. Unfortunately there's no real way to check or clean the CCV without destroying it. They usually become so brittle that when you go to take it apart or remove it it falls apart in your hand. Sometimes you can hear them hissing when they're starting to fail. Follow that hose to the valve cover. There's a port on the back of the cover that the hose attaches to. This port sometimes gets gunked up with crud/sludge and restrict airflow. It will also cause your idle to increase. You can stick a q-tip or something in the port to clear the air passage, but I wouldn't recommend doing so because it's just going to fall right onto your cam and likely work it's way into the engine where it might cause other problems. The best way to clean this port is to remove the valve cover and clean it. This involves a little more work, but it's always nice to take a looksy at your cam/valvetrain. You'll need to order a new valve cover gasket and spark plug hole gaskets(I think they're sold together as a kit). First try the two things John and I mentioned. If those don't work, try the crank case vent valve(CCV) and the crank case vent(valve cover air passage). Best of luck, keep us posted.

[bmw_pwr]

sounds good, i will be doing that today, hopefully wont take to long as i have never done those things, i am good with cars(but engines..) haha :P so if u have a pic to show what the ccv is and how to do that stuff step by step it would be exxxxxtremely helpfull,
wish me luck and thinks for the help..,
ill keep ya guys updated.

[bmw_pwr]

btw, i saw the mass air flow hose, the one goes in a huge curve, is cracked, nnot sure if all the way through, but i can see its cracked. ;( should i change that?
i think i should.. well that could be the problem.. way i go do the stuff..

[cooljess76]

Originally Posted by bmw_pwr

btw, i saw the mass air flow hose, the one goes in a huge curve, is cracked, nnot sure if all the way through, but i can see its cracked. ;( should i change that?
i think i should.. well that could be the problem.. way i go do the stuff..

If you can see cracks, I can almost guarantee it's time to replace the boot. Sometimes you can't even see the cracks as the splits are sometimes hidden in the ribs of the boot. Any leaks downstream of the MAF will cause funky idle problems and possible misfire codes. Here's a diagram showing the CCV and valve cover orifice that I mentioned. The CCV is a black plastic disc just aft of the intake manifold(#16 in the diagram). Follow that hose to the valve cover and you'll see where it connects. It's that orifice that becomes clogged with gunk:

http://www.realoem.com/bmw/showparts...62&hg=11&fg=15

Here's your ICV, it's #9 in the diagram and it attaches to your throttle body:

http://www.realoem.com/bmw/showparts...02&hg=13&fg=15

[pdxmotorhead]

I bought one at the dealer was 28 dollars....

Dave

[bmw_pwr]

sooo, this is what happened, i take my car to go get some brake cleaaner, stop at my neighbor to show off my new car, i see some intense leaking underneath coming from the exhaust.. so i was like.. what is that.. and as i pulled out of the driveway, my brake paddle was being funny.. so i puled up and smelled the fluid. like a good detective( he went north!!!) i mean, brake fluid, and it was leaking a lot, so i said, here we fuzing start the problems... jacked the car up.. guess what i find.. a brake hose dripping.. grrr.. allright, let do this( never done a brake hose b4..) so i go buy a new one, partsource right beside my house, walking distance.. so i buy a female one side, and male other side(inner flexible brake hose) come back look at the broken one, and the new one, went back, 7 min walk.. this is not the right one, he ensures me it was, but i forgot to tell him it was the inner, so i go back to the car, i killed myself trying to take out the broken one that was rusted as hell, and what do i find.. both female ends, go back to partsource.. they didnt have it.. grr so i buy another one that is for another car, but i am not stranded at home the whole weekend.. so on monday im getting the good one and changing back to the factory one.. haha so i dint get a chance of doing my idle problem, looks like its gotta be for tomorrow.
but lost in all that dance with my car 6 hours.. i know i suck, i almost gave up at one point.. but no way in hell im letting Canadian tire fix anything for me again.. haha

[xxxJohnBoyxxx]

Hey look at the bright side at least you were in a driveway and not hauling balls down the road to a red light with cars in front of you when you hit the brakes only to find out you have no brakes. That would have been a very unhappy ending for your new car. I bet you will find the idle issue is on that cracked hose from the MAF sensor to the TB.

Cars driven on salty roads are a bear to work on since the whole under body is usually rusted from all the salt. You have started off on a hard project like a rusted brake line which is no fun, you have passed the test and are now a DIY'er and you can tackle those projects now and save money by doing it yourself You need to get a Bentley Manual since it will help you with a lot of projects. You can purchase one or look for a free PDF download on the internet since there are a lot of bootleg copys out there. If you have a problem finding a Bentley manual PM me


Good luck, John S

[bmw_pwr]

so, i did the brake cleaner thing, it didnt rev or made any diff sound.. but i did disconect the MAF sensor, and the idle went down to 800ish, a lil bit rough tho, bit i am guessing it is the maf sensor..
plus, while i was doing the brake line.. i noticed the sway bar(goes from one side to the other side of the car and is holding the car) "i think" rear driver side is cracked and rusted to hell, that is not good, and just wondering if thats fixable.. plus the front driver also(there is a connector that goes from one side to the other side, around the engine, and is held by 2 rubber brackets( really bad with terminology(and English)) that bracket has been broken, with the piece of mettal moving freely, ill take some pics to show ya guys..
till then, i worry bout school..
Marcos

[mohaughn]

Those are common rust failures. You will have to have the rusted out metal cut out, and replacement pieces welded back in. If you are lucky, it is just the front sway bar mounting point, in which case, they sell those as a straight replacement part that can be replaced. Worst case, the metal behind that bracket is also rusted and that is a much more involved repair.

For the rear, if it is just the end links, those are replaceable. Same thing on the actualy body side brackets. If they are rusted, they need to be cut out and new ones welded back in.

[bmw_pwr]

so i been playing with the idle...
i cleaned everything, even the lower and upper intake magnaflow(i think thats whats called).. so the car is going from 300 rpm and then after goes to 1500 again, and then goes to 800, stays for a bit revs to 1500.. grrr, so fustrated, changed all the damn hoses and everything.. so i cleaned the ICV, throtle body, changed the mass airflow sensor to 3 diff ones, no luck, today i just picked up a ICV from a 318i 94 from junk yard, it looks a lil bit diff.. but well see what happenes...i also got the mass iar flow.. the tube, mine is a lil rough.. and got a throttle body from the 94 too.. ANY IMPUT, please help me figure this thing out.. this is driving me insane.. the hunting idle is making me crazy, and there isnt many things i can think of i can do to fix it... maybe injectors? anyone think that might be the casee??

thankss

M.G.

pss, some pics from my car..

[dave45056]

What year is your car? And did you ever replace the air intake hose (the one goes in a huge curve)?

[xxxJohnBoyxxx]

I don't think injectors are the issue. It is very hard for us to diagonis issues over the internet. We will keep trying. The ICV should have been removed and cleaned with cleaner a a q-tip, did you do that? Also the new one should match the old one that you are replacing...Make sure you clean that on very good before installing it. If it is not cleaned it will do the same thing you experiencing now, hunting idle

Originally Posted by bmw_pwr

so i been playing with the idle...
i cleaned everything, even the lower and upper intake magnaflow(i think thats whats called).. so the car is going from 300 rpm and then after goes to 1500 again, and then goes to 800, stays for a bit revs to 1500.. grrr, so fustrated, changed all the damn hoses and everything.. so i cleaned the ICV, throtle body, changed the mass airflow sensor to 3 diff ones, no luck, today i just picked up a ICV from a 318i 94 from junk yard, it looks a lil bit diff.. but well see what happenes...i also got the mass iar flow.. the tube, mine is a lil rough.. and got a throttle body from the 94 too.. ANY IMPUT, please help me figure this thing out.. this is driving me insane.. the hunting idle is making me crazy, and there isnt many things i can think of i can do to fix it... maybe injectors? anyone think that might be the casee??

thankss

M.G.

pss, some pics from my car..

[bmw_pwr]

yes, i am replacing the air flow hose (the big one that goes in a curve) tonight.. right now actually. And the ICV i cleaned it about 20 times with carborator cleaner with a Q-tip. The thing inside is not quite loose.. although it moves around when i shake it hard.

The car's year is a 1995 318 TI. It has an M-42 engine on it.

P.s.: Whenever i disconnect the air-flow sensor, the car idles normally.. but slightly lower than the normal. Also, i pretty much changed all the hoses from, the air-flow intake. Going back to the car right now.. any input would be reallllly appreciated, and any questions.. just ask and ill tell you what's going on to help diagnose this machina.