Erratic Idle/Stalling on '98ti

[danimal17]

Ok... so I'm have the classic erratice idle problem at about 170,000 miles and really some input because as many of you know, it's getting very frustrating. The idle is shaky and this has been for a while now. The rpm's drop slightly, then rev slightly. Just recently, the car has been stalling when warm after stopping at a red light. Things I've tried: -Swapped out 3 different ICV's (all used, but working). Tested them electronically and cleaned them with carb cleaner. -Tested and changed throttle position switch -Tested MAF electronically -Inspected and changed 1 vacuum hose -Tested cam position sensor -Changed spark plugs -I have NO codes or CEL! Any ideas???

[anthony318ti]

Originally Posted by danimal17

Ok... so I'm have the classic erratice idle problem at about 170,000 miles and really some input because as many of you know, it's getting very frustrating. The idle is shaky and this has been for a while now. The rpm's drop slightly, then rev slightly. Just recently, the car has been stalling when warm after stopping at a red light. Things I've tried: -Swapped out 3 different ICV's (all used, but working). Tested them electronically and cleaned them with carb cleaner. -Tested and changed throttle position switch -Tested MAF electronically -Inspected and changed 1 vacuum hose -Tested cam position sensor -Changed spark plugs -I have NO codes or CEL! Any ideas???

How old is your battery. Does it rev up when the Efan kicks in? How does it idle with the AC on?

[danimal17]

I bought a new battery about 2 years ago. I didn't think to try the AC becuase I never us it anyway. It doesn't seem to be revving only when the fan comes on either. It could happen any time when idling, with the engine hot or cold. And the rpm's may go slightly up and down several times while sitting at a single red light.

If the AC makes me stall while idling, do you think it's my battery?

[spidertri]

Have you checked/replaced the intake boots?

[anthony318ti]

Originally Posted by danimal17

I bought a new battery about 2 years ago. I didn't think to try the AC becuase I never us it anyway. It doesn't seem to be revving only when the fan comes on either. It could happen any time when idling, with the engine hot or cold. And the rpm's may go slightly up and down several times while sitting at a single red light.

If the AC makes me stall while idling, do you think it's my battery?

After i bought my ti it used to do somewhat same but never stalled it was just a slight dip in rpm than up again or up and down again i checked everything than i tested the alternator while running and i noticed power fluctuated and as it did my motor acted as it id. Changed out the alternator and the battery and now my car is fine. But that is my experience on the electrical side as for the mechanical aspects I'm sure the senior members would have better advise and experience.

[danimal17]

Thanks for the reply guys. I will probably have to change a boot and check the alternator as well. One of my intake boots was cracked, but I swear it has been since before this problem started. So I took it off and totally wrapped it up with electrical tape until a new one is ordered. Still no change though.

How might I go about checking the output voltage of the alternator?

[anthony318ti]

Originally Posted by danimal17

Thanks for the reply guys. I will probably have to change a boot and check the alternator as well. One of my intake boots was cracked, but I swear it has been since before this problem started. So I took it off and totally wrapped it up with electrical tape until a new one is ordered. Still no change though.

How might I go about checking the output voltage of the alternator?

One easy way i do it is start the car disconnect the battery terminal + or - doesn't matter just take one of them off. Than key in your multimeter to DC and connect the com of the multimeter to the (-) of the car and the other to (+) car terminal see if it fluctuates. From my exp an alright reading should be around 13V etc etc but what we really looking for is power spikes where the voltage will just drop drastically. If your alternator regulator is kinda stuffed than it may stall the car after you disconnect the battery at that point may want to take it to an auto electrician for further diagnostics.

[danimal17]

Ok thanks.

Anthony, do you really live in Fiji?

[anthony318ti]

Originally Posted by danimal17

Ok thanks.

Anthony, do you really live in Fiji?

: ) Yep i live in Fiji. Have you been here? I live on the main Island Viti Levu.

[anthony318ti]

How are you getting along with your problem?

[danimal17]

No, never been to Fiji, but would love to go someday and probably wouldn't want to leave. It's just interesting to me that we're talking because I didn't even know there were 318's driving around there! I haven't really had time to check anything lately. I want to check the alternator like you said and am still thinking about how exactly to test the stuff Junk mentioned. One more thing though, have you guys ever electronically tested the O2 sensors? The Bentley manual shows how, but the pic in there of the sensor for the M44 engine is different than what mine looks like. It shows a connector with several pins that can be exposed and touched with a meter, but my O2 sensor looks more like a spark plug with no access to the wires.

[anthony318ti]

Originally Posted by danimal17

No, never been to Fiji, but would love to go someday and probably wouldn't want to leave. It's just interesting to me that we're talking because I didn't even know there were 318's driving around there! I haven't really had time to check anything lately. I want to check the alternator like you said and am still thinking about how exactly to test the stuff Junk mentioned. One more thing though, have you guys ever electronically tested the O2 sensors? The Bentley manual shows how, but the pic in there of the sensor for the M44 engine is different than what mine looks like. It shows a connector with several pins that can be exposed and touched with a meter, but my O2 sensor looks more like a spark plug with no access to the wires.

Lol yeah Fiji is such a small island nation who would think we have 318's here. But really we have heaps of 3' 5' 7' series but not many 318ti and 316i compact. Ill post something soon on the O2 sensor.

[anthony318ti]

Abit off topic but here is something i came across which would be nice to keep on file. http://wedophones.com/Manuals/BMW/19...g%20Manual.pdf

[anthony318ti]

DIY on replacement of O2 Sensor still nothing on testing. argh http://www.pelicanparts.com/bmw/tech...-O2_Sensor.htm

[anthony318ti]

98ti from my research have a 4 wire pre-cat o2 sensor is this the same as yours or does ours have tow or one wire coming out of it. Ummm testing them i know that a good sensor will read close to 0 ohms.