> Yea, runs poorly in neutral, also...same thing.
> On Thu, 10 Nov 2005 11:46:19 -0800, "Randy G."
> <frcn@DESPAMMOcncnet.com> wrote:
>>Does it run poorly in Neutral like in Park?
>>Geronimo <email@example.com> wrote:
>>> Its an 89 740 GL sedan, non-turbo, B230 F engine. Jetronic L
>>>system. I am not sure I have it timed right. It idles rough
>>>(erratic RPM....500-800 RPM), it has a strong miss every few seconds
>>>(when the RPM dips).....but only when you have it in park! When put
>>>into drive--- sitting still--- the idle RPM is perfectly stable,
>>>roughness/missing is completely gone. And when moving, the miss is
>>> Went and spent a lot of $$ for new dist. cap & rotor, new plugs,
>>>new spark plug wires. Now I notice that it is only running badly when
>>>in PARK, so it wouldn't have been any of those parts! If not timed
>>>right, can this cause the ign. control module to maybe set the advance
>>>way off for PARK, but set it correctly when in DRIVE?
>> __ __
>> Randy & \ \/ /alerie's
>>'90 245 Estate - '93 965 Estate
>> "Shelby" & "Kate"
The ignition timing on that motor (if it's adjustable at all) needs to
be set, with the engine FULLY warmed up, as an ECU monitors the coolant
temperature, and gradually retards the ignition from an advanced
condition that exists with the coolant anything but fully warmed, this
allows the engine to run 'nicer' when cold.
The same ECU also monitors the status of the neutral start switch, very
slightly advancing the ignition timing if a gear is selected, helping to
prevent stalling while the engine is idling in gear.
I'm not sure if the ignition timing on the B230F is picked up from the
camshaft via a hall sensor in the distributor or the crank shaft via a
position sensor 'reading' the flywheel, if it's the later, AFAIK
can't actually change the timing, but, if you rotate the distributor too
far either way, then it's quite possible to have the ignition firing
sparks off, when the rotor arm is actually not close enough to a spark
lead, to actually get to a plug properly, hence causing a slight or not
so slight misfire.
Just my 2 pennies worth,