BimmerFest BMW Forum banner

E36 rough idle until warm

5K views 17 replies 6 participants last post by  ZeGerman 
#1 ·
Hey guys! New here! My names Brandon from Green Bay Wisconsin and I just picked up a 98 e36 4cyl

My issue with the car is when i come out in the morning to start her she take a bit to start and runs really rough almost like not on all cylinders and almost sounds like a knock coming fr the motor but this all disappears once the car gets warmer. It's done this for a bit now and I just put a new cam sensor in hoping that would fix it...

Hopefully you guys can help me! Thanks guys!!!
 
#4 ·
not necessary to bump....

anyway, would need a little more information, such as have you done the following??

replaced plugs with the proper units?? (no bosch +4)
cleaned the idle control motor (iac) and throttle plate??
proper grade fuel??

any check engine lights on?? (verify the self check status when you key up, all ofthe lights should come on)

if you have an obd2 scan tool or even a code reader, check for pending codes. record them and check those out.

verify there are no vacuum leaks, check the intake boot and vac lines for cracking/softness,

how many miles on it??

since you just got it, i would suspect that these above ites are questionable, so i would also suggest a can of seafoam through the intake.

there are some other 4 banger specific issues that may be present, but i am unaware of them at this point, however, this is a good start to get the basics out of the way.

i'm sure thre will be others to chime in on this later.






df
 
#6 ·
cleaned the idle control motor (iac) and throttle plate??
My 1996 E35 Convert with 116K miles has the same problem, so I thought it would be best to add to this thread as opposed to starting a new thread.

Anyways.

Curious, how difficult is it to get to the Idle Control Valve on a E36 with the E52 engine?

My 1996 E36 Conv also has a poor idle (low rpm and rough), have been reading up on possible causes. Seems like the ICV is next on the list. Have already ordered a new hose and the connector that often breaks. Are there any other consumable/breakable items I should procure before ripping into this?

FYI - I changed spark plugs today, went with the four-prong NGK plug. The ones I pulled out were Bosh two-prong units and probably the original units. Car seems to run better now, well except for the crappy idle.
 
#5 · (Edited)
Yeah, since you just got the car, you basically have to go through and check everything since the whole car is a big unknown. I'd pay particularly close attention to any and all vacuum lines, spark plugs, spark plug boots, and make sure there's no oil in the plug wells from a leaking valve cover gasket, as well as make sure you don't have any cracks in the intake boot. If all that stuff checks out okay, we'll have to delve deeper.
 
#8 ·
The plugs you want are cheap. THey are the NGK BKR6EK. They are such a FAQ that many of us long time poster's have the product number memorized.
 
#12 ·
The bosch +4 platinum plugs are also a known issue with these cars. Yes, the plugs may look 'perfect', but they are the wrong plugs for these cars.
 
#13 · (Edited)
A slow start and knocking sound sounds like a plug/coils issue to me. The plugs are timed in a sequence with electrical bursts from the coil pack. If the coils are not snug, in the wrong cylinder, or faulty, this issue can happen. You can have a slow start, no start, and/or a bad idle. Since you checked the plugs already, check the coil pack. Sounds like some bad misfiring going on.
 
#16 ·
I saw the title of this thread and thought to myself: "torn intake boot". And yeah, by the time you hit 120k, all of the shocks, struts, and bushings are usually pretty well shot. I replaced the suspension and bushings on my car at around 100k, and while the shocks were still working fine at that mileage, the bushings were totally gone. Like GONE, gone. If yours are the originals, they're probably on their way out if they haven't failed already. Unfortunately, when you replace the bushings, you'll have to get another alignment.

Glad to hear that you got your E36 sorted out, though. Should be a lot more pleasant to drive now.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top