e34 idling not smooth!!!

[kenny 88]

Hi guys!Just join this club not long ago.....1st time posting. need some advise from you xperts.Driving a e34 525i 89' and have been having this problem for some time, when idling got this funny mild kick from the engine which i didnt have when 1st got the car 3yrs ago. changed the idle valve, distributor cap(i think) but problem still there....is it a common thing??? Very irritating and mechanic pun don't know what is the problem.... Any idea what is causing it?????Thanks!!!

 

[E34EuroTouring]

Did you have spark plugs changed recently too ?. Or recently checked, if one or two plugs are foul, it will cause irratic idle too.

But I really think, your AFM may be very dirty or may need "internal" conditioning. First try to clean it with Carb Cleaner and also the intake elbow. Since your ICV is new, did you change some of your hoses as well. I found that small hoses to ICV can be filled with oil and needs to be replaced. These hoses are rather cheap from the dealer.

The other thing is to check for vacumn leaks. The vacumn hose from the FPR to the intake manifold can easily come lose or the previous owner might have just removed it!. There is also vacumn hoses out of the brake booster (driver side of engine compartment that had small hoses (less than 1/2 inch diameter). If these or the small check-valves are broken, replace them as well.

I would not recommend opening up the AFM if you do NOT have a spare. If you break it, the car would not start or would hardly run at all!. Too dangerous, just clean it well with Carb cleaner and clean rag. Put them all back and it could improve the idle significantly.
Good Luck.

 

[kenny 88]

Originally posted by E34EuroTouring@Oct 6 2005, 10:22 PM
Did you have spark plugs changed recently too ?. Or recently checked, if one or two plugs are foul, it will cause irratic idle too.

But I really think, your AFM may be very dirty or may need "internal" conditioning. First try to clean it with Carb Cleaner and also the intake elbow. Since your ICV is new, did you change some of your hoses as well. I found that small hoses to ICV can be filled with oil and needs to be replaced. These hoses are rather cheap from the dealer.

The other thing is to check for vacumn leaks. The vacumn hose from the FPR to the intake manifold can easily come lose or the previous owner might have just removed it!. There is also vacumn hoses out of the brake booster (driver side of engine compartment that had small hoses (less than 1/2 inch diameter). If these or the small check-valves are broken, replace them as well.

I would not recommend opening up the AFM if you do NOT have a spare. If you break it, the car would not start or would hardly run at all!. Too dangerous, just clean it well with Carb cleaner and clean rag. Put them all back and it could improve the idle significantly.
Good Luck.

Thks euro touring for yr reply and advise.

Currently using super 4 Bosch spark plugs which has improved the idling and many hoses has been changed during this 2 years but still facing the same problem.

One well known mechanic even says my throttle switch is faulty which i did changed a new one abt 1 1/2 yrs ago for RM150.00, and he changed it and charged me the same price for a used one......wonder what the cost for a new one now?

Tried fitting a new AFM last year but the engine idling was even worse, my mechanic was shock to see that happening, so put the old one back.

Sorry to trouble you my friend, one more thing is that when i start the engine in the morning the normally the rev is high and goes lower after a while for most cars......mine dont go down unless i switch on the a/c if not the rev can reach 1000rpm when i stop after driving a short distance. and when i off the a/c before switching off the engine the revs goes up again.....headache lah!!!! Hope u can help me here.....Thks again.

Maybe i should send to another mechanic for a check for this problem......any recommendation??? Heard that Antera in bt 14 Puchong is good but not sure where?

Better stop here.....too long leh!!


Cheers!!

 

[E34EuroTouring]

When your mechanic tried a different AFM, did he RESET the ECU by pulling the battery and connecting +ve to -ve terminals. Wait 10 mins then reconnect back. You need to drive the car HARD for more than 30 mins for the ECU to "learn" the variance of the AFM voltages.

Usually, the ECU adapts to voltage values very slowly. So replacing a BETTER afm without reseting the ECU will be *worse* as the adapted values are wrong in the first place. Yep, just like rebooting your Windows PC.

 

[kenny 88]

Originally posted by E34EuroTouring@Oct 8 2005, 07:00 PM
When your mechanic tried a different AFM, did he RESET the ECU by pulling the battery and connecting +ve to -ve terminals. Wait 10 mins then reconnect back. You need to drive the car HARD for more than 30 mins for the ECU to "learn" the variance of the AFM voltages.

Usually, the ECU adapts to voltage values very slowly. So replacing a BETTER afm without reseting the ECU will be *worse* as the adapted values are wrong in the first place. Yep, just like rebooting your Windows PC.

Thanks euro touring,

Will check with my mechanic again.

Cheers!!!

 

[moots]

Try cleaning the throttle body.I did this on my e30 and the idle improved tremendously.Remove it totally and immerse it in petrol if you have to.Clean out all the small orifices and sensing holes.

 

[kenny 88]

Originally posted by moots@Oct 10 2005, 12:32 PM
Try cleaning the throttle body.I did this on my e30 and the idle improved tremendously.Remove it totally and immerse it in petrol if you have to.Clean out all the small orifices and sensing holes.

Thanks moot for the advise.

how do i remove the throttle switch? is it easy to install it back?

will try to do it this weekend and will let u know the results!!

where can i get the gasket for the throttle body...notice mine is missing. can i use if i do my own gasket? please advise.

thanks n cheers!

 

[vjayprakash]

i once had a same problem on my previous E34 525i and i managed to solve it by changing a new rotor in my distributor.

Try it.New rotor is not expensive for Motronic engines.

Good Luck

 

[kenny 88]

Originally posted by vjayprakash@Oct 11 2005, 06:11 PM
i once had a same problem on my previous E34 525i and i managed to solve it by changing a new rotor in my distributor.

Try it.New rotor is not expensive for Motronic engines.

Good Luck

hi there!

l've changed my rotor and distributor abt 2yrs ago. lt did help but not for long...back to the same problem.

Will try to clean it this weekend when cleaning my throttle body.

Thanks n cheers!!!

 

[moots]

Originally posted by kenny 88+Oct 11 2005, 01:13 PM-->QUOTE (kenny 88 @ Oct 11 2005, 01:13 PM)

 

[bmwky]

Originally posted by kenny 88+Oct 10 2005, 12:27 PM-->QUOTE (kenny 88 @ Oct 10 2005, 12:27 PM)

 

[kenny 88]

Originally posted by bmwky+Oct 13 2005, 01:24 PM-->QUOTE (bmwky @ Oct 13 2005, 01:24 PM)

Originally posted by kenny 88@Oct 10 2005, 12:27 PM

 

[E34EuroTouring]

You can use silicone gasket rather than cut the paper. The idea is to seal the interface mount to the manifold. Apply sparingly from a squeeze tube and spread evenly then put the TB back and screw in the unit. That will be fine. You might want to check your vacumn tubes and replace them. A vacumn leak or stuck tube can lead to erratic idle.

Good luck.

Yes; Moots was right M20 engine is easier to fix and troubleshoot.

 

[kenny 88]

Originally posted by E34EuroTouring@Oct 13 2005, 11:33 PM
You can use silicone gasket rather than cut the paper. The idea is to seal the interface mount to the manifold. Apply sparingly from a squeeze tube and spread evenly then put the TB back and screw in the unit. That will be fine. You might want to check your vacumn tubes and replace them. A vacumn leak or stuck tube can lead to erratic idle.

Good luck.

Yes; Moots was right M20 engine is easier to fix and troubleshoot.

Thank a lot guys for all the HELP!!!!

Will attend to the fews suggestions posted earlier and will let u guys know the outcome yeah.

Anyone knows when is the next TT in PJ???? Would like to meet you guys.....maybe even for some HH drink, whichever one pun ok lah.

Have a nice weekend guys.

Cheers!! :yahoo:

 

[kenny 88]

Originally posted by kenny 88+Oct 14 2005, 11:31 AM-->QUOTE (kenny 88 @ Oct 14 2005, 11:31 AM)