Re: [bmw] 85 528e having a hesitation problem.

[ebainesjr@xxxxxxx]

Lee - two things to consider.

1. Get the Bentley manual.  Haynes is awful.

2. The idle surging issue may be the ICV (idle control Valve).  When the valve doesn't work, the engine surges to about 2500 RPM, then dies back to 600, then surges again, in cycles lasting about 5 seconds.  The car will run, but when you come to a stop at a red light the guy in the car next to you will think you're a real jerk for constantly revving your engine!  Check the electrical connections at the ICV (they broke on my '86 528e and needed to be resoldered). Also try cleaning the valve out, using WD40.  Over time the valve can get sticky with deposits -- cleaning it with WD40 allows the valve to move much more freely.   If this doesn't solve the problem, you can check for proper operation of the valve by applying 12 volts to the two leads -- the valve plunger should close with a definite snap.  The resistance between the two leads should be about 10 ohms (with electrical connector unplugged).  Please note - my car uses a two-lead valve; some others have three leads.  Check the Bentley manual!

Good luck,

-Chip
>  
> I have an 85 528e .[snip]... Sometime while holding steady the engine will lope
> from 1800 to 1000 RPM back and forth until I either let up on the pedal
> or floor it. I have changed the cap, rotor, in tank pump, all fuel and
> coolant sensors, main fuel pump, ECU, ICM and all fuel line that looked
> shot. 
> Lee 85 528e 157k
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