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ibnyinc
10-09-2009, 01:31 PM
i just picked up a 1994 e34 540i auto and it has problems.
when at idle the car shakes i mean you rock when you sit in it.the check engine light is lit but will go out sometimes when i hold the revs between 1500 and 2000.

i heard about the nikasil/alusil problem and check the block and i have the alusil so thats one hurdle scared the .... out of me.

i also had a freind power brake the car with light revs and disconnected each coil for misfire but all 8 seem to work.

then i tried disconecting one sensor at a time to see if it makes any difference with no avail. maf, tps, idle control, tracktion control, map.

i am leaning toward the intake manifold gaskets leaking vacume but before i commit to the job and $ i want to rule out any other tests or sensors that can cause this.

anyone who has had this problem and solved it i would love to hear your solution or advice and if any one has a diagram of all the enigine parts location and or a repiar manual download for this car. it will be greatly apprieciated.
thank you in advance.

bdejong11129
10-11-2009, 10:23 AM
Try the good old car cleaner spray test. Spay the car cleaner all around the intake, DONT FORGET the pcv plate on the rear of the engine.

I had a consistant rough idel, CEL 1222, and 1232 code. It ended up being a missing vacuum plug on the pcv plate. Replaced it and it went away, no more CEL and the idle is solid.

ibnyinc
10-12-2009, 10:22 AM
thanks for your reply
i tried cleaning the throttle body and removed the foam insulater from the pcv plate and checked for the plug its still there and cleaned all around the plate with no change.

update on further testing that has been done.

took out each coil checked the ohms and they are all under 2 ohms so coils are good.
removed spark plugs and checked compression on all cylinders and they are all the same around 170-180psi good compression. the spark plugs looked old so i replaced them with bosch platnium quad head.

the engine seems to rev better without the sputter not like before. the enine feels smooth and strong when reved up but still shakes when idling.i checked motor mounts and they are ok.

yesterday i took it for a little ride afterthe cleaning and spark plug change and when i started the car the cel was off and drove it 5 blocks to the highway was on highway i noticed that the cel stayed off and car was running great. i was on the highway for 10min and all was fine. when i got off the highway and stopped at tthe light the engine idled perfect. after about 6-8 seconds the back of the car lifted a little like when you put it in reverse and felt a thump like something ingaged and cel went on and started shaking agian.

im thinking its something electrical or some sensor that the cumputer is picking up and trowing it in saftey or something its very strange the way it happens runs perfect and as soon as i stop 6 sec later and back to same problems.

anyone experience this before or have any clues what might cause this i will like to here your thoughts and sujjestions.

superblackman31
10-12-2009, 11:12 PM
my 91 e34 has had some serious misfires and the most irritating idleing issues ever. i changed plugs and after i changed the wires it runs smooth. the only other possibility is the air intake valve (loose or clogged). i have the check engine light come on maybe once a month now due to that. but i still have no problem driving from phoenix to san francisco with over 206k miles on it.

v8bimmer
10-14-2009, 12:15 PM
I had bad idle shaking too. I replaced the motor mounts and the guibo. Runs perfectly now.

ibnyinc
10-16-2009, 11:16 AM
i tried the 5 times in five second pressing the acclerate pedal to the floor with car off and ignition on but no cel flashing. am i doing it wrong or is there anything i can do to read the cel code.

jimoreno
10-20-2009, 10:51 AM
It takes some tries to get it to work properly. Make sure that the key is in the ignition mode (lights one but engine not running) and just do it quickly. The other way to read the codes is to get a tool, like a Peake reader. I have one question tough, Have you done a tune up to the car (oil, air and fuel filters, spark plugs, etc.)? Maybe you have a bad plug and thej fix is easier than it looks.
Good Luck!

ibnyinc
10-21-2009, 11:24 AM
i have an update on this problem and it seems from reading the forums that this is a very common problem with this model bmw.

i read one tread that this guy was having the same problem that i am having.
rough idle, car shakes, puff of smoke only when first started, cel.
the problem that he explianed that i knew it was the same as mine was a loud screaching niose comming from the back of the engine.
what he figured out was to take the dipstick out and the noise went away for him.
so i tried it.
started the car with the puff of smoke, started running rough, searching for the idle 500-1200, had to help it as it felt it would stall, after a minute it idled at 450-500, let it warm up shakeing about 10min and the screaching sound that i thought was the tourqe converter started.
i took out the dipstick and got a lot of suction from the pipe and the screaching stopped. i did it a few times and sure enough it was the pcv plate making that sceaching so i put my hand flat on the pcv and felt a little suction coming from the pcv plate.

as i thought before on my earlier thread i now feel after this test that the pcv plate needs replacing and since it is easier to take the manifold out i would do all the intake gaskets, throttle gasket, o-ring on the pipe from the pcv, pcv gasket and the pcv plate.

i found all the parts for $125 shipped and i am going to order them tonight.
here is where i need your guys help. do you thing that this is causeing all my problems and i should definitely do the gasket change.
also the manual does not have details on removing the intake and what tools i would need so if anyone did this job before and have info or pics, what to look out for, any advice before i dive into this it will be very helpfull. thanks.
i will post the out come of the repair as it will definitely come in use for someone else out there.

ibnyinc
10-31-2009, 06:23 AM
i got the parts in and started the job yesterday. i got the intake off and removed the pcv plate and went to install the new one but the new one is different then the stock one it has an extra plug on the back faceing the drivers side. i dont know if autohaus sent me the wrong one or thats the way they make the new parts. it looks loke i could use it with a plug should work the same i have to see what autohaus will say to do or what plug i can get from them to fit that size vent. did anyone that this job get the same pcv plate and what did you do to get it to work on the e34 540i intake. please let me know if you have any sujjestions

i tried to attach a picture of it i dont know if it will show as i am new here and dont know how its done yet but if the pic dont show you can go to this link to see the part and its the plug with the red o-ring. http://www.autohausaz.com/search/product.aspx?sid=vc3bw555ogzw4d4541512e45&partnumber=11-61-7-501-562

ibnyinc
11-01-2009, 11:21 PM
finished the job just went to auto zone and bought the assorted rubber plug pack for 2.99 and it fit perfect.

the engine runs new again i cant beleive that few gaskets and a pcv plate made such a differnce. idles perfect, no shake , no smoke when starting, no screaching sound, no cel, trans shifts smoother, fuel economy is good, power is back, better thortle responce. i could not be happier. had my doubts but was all worth it.

thank you all for your replies and help.

BOLTEYES-82
11-01-2009, 11:28 PM
mine was an idle control valve, after i had changed many other things on advice of many people doom & gloom merchants told me my engine was bad due to nikasil,

if you hear about nikasil issues be informed that a 1994 should have been alusil from the start and if not would have been dead unlucky if it wasnt warranty changed.

honestly before you do anything else check the idle control valve toothbrush and carb cleaner often does the trick but not alwats if you know a decent honest mechanic then ask him to check the resistances of the ICV against the spec.

or buy a second hand one an E36 M3 evo has the same unit use www.realoem.com its very useful

ibnyinc
11-02-2009, 06:29 AM
mine was an idle control valve, after i had changed many other things on advice of many people doom & gloom merchants told me my engine was bad due to nikasil,

if you hear about nikasil issues be informed that a 1994 should have been alusil from the start and if not would have been dead unlucky if it wasnt warranty changed.

honestly before you do anything else check the idle control valve toothbrush and carb cleaner often does the trick but not alwats if you know a decent honest mechanic then ask him to check the resistances of the ICV against the spec.

or buy a second hand one an E36 M3 evo has the same unit use www.realoem.com its very useful

the problem was fixed with the gaskets and pcv plate i dont need to check icv its working fine now purrs like a kitten.

BOLTEYES-82
11-02-2009, 09:33 AM
good for you man