1994 F 150 4.9 timing information wanted

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bonanzaman@gmail.com - 21 Jul 2006 03:03 GMT

I've got a 1993 F150 with a 4.9 inline 6 and I';m curious about the
timing.

When I look at it with a timing light its above the 12 degree mark and
when I advance the throttle, it goes up a little then stays at the 12
degree mark.
What should the timing be and how can it be set?

Thanks

Dave

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monkeyboy - 21 Jul 2006 08:51 GMT

>I've got a 1993 F150 with a 4.9 inline 6 and I';m curious about the
>timing.
[quoted text clipped - 7 lines]
>
>Dave

Isn't ther a vehicle emission information control decal under the hood, core
support area. That has your timing info on it as for checking and adjustment
This procedure is for Distributor Ignition systems only. EI low data rate and
high data rate systems cannot be adjusted.
4.9L/5.0L/5.8L/7.5L DI Remote Mounted ICM Computer Controlled Dwell (CCD)
(System H)

Procedure 1994 4.9 truck
1. Place transmission in PARK or NEUTRAL, A/C and heater in OFF position.
2. Connect an inductive timing light, Rotunda 059-00006 or equivalent.
3. Disconnect the single wire in-line SPOUT connector or remove the shorting
bar from the double wire SPOUT connector.
4. Start the engine and allow it to warm up to operating temperature. To set
timing correctly, a remote starter should not be used. Use the ignition key
only to start the vehicle. Disconnecting the start wire at the starter relay
will cause ICM to revert to start mode timing after the vehicle is started.
Reconnecting the start wire after the vehicle is running will not correct the
timing.
5. With engine at timing rpm if specified, check/adjust initial timing to
specification.
6. Reconnect single wire in-line SPOUT connector or reinstall the shorting
bar on the double wire SPOUT connector. Check timing advance while varying
engine speed to verify distributor is advancing beyond the initial setting.
If it is not, refer to Section 2A, Quick Test.
7. Remove test instruments.

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dave - 21 Jul 2006 13:25 GMT

I mis-Typed the title, it's a 1993 4.9 F150.
Is the 93 and 94 the same procedure?

No there isn't a sticker with this information.
Yep, it's the distributor type ignition system.
Do you have the actual timing specifications?

Thanks
Dave

> Isn't ther a vehicle emission information control decal under the hood, core
> support area. That has your timing info on it as for checking and adjustment
[quoted text clipped - 25 lines]
> Message posted via CarKB.com
> http://www.carkb.com/Uwe/Forums.aspx/ford-truck/200607/1

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aarcuda69062 - 21 Jul 2006 14:48 GMT

In article
<1153484756.167875.281720@i42g2000cwa.googlegroups.com>,

> I mis-Typed the title, it's a 1993 4.9 F150.
> Is the 93 and 94 the same procedure?
[quoted text clipped - 5 lines]
> Thanks
> Dave

Base timing on all EEC-IV distributor ignition systems is 10*
BTDC.

Make sure that you disconnect the spout connector and not the
octane adjustment plug (they look identical)
IIRC, the spout circuit is a yellow wire w/green stripe.

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dave - 21 Jul 2006 19:19 GMT

Are these connectors located on the distributor?

Also, currently the timing seems to jump a little, kind of like there
is a loose timing chain.
Just a brief bleep of 5-7 degrees. What would cause this?

thanks again

Dave

> Base timing on all EEC-IV distributor ignition systems is 10*
> BTDC.
>
> Make sure that you disconnect the spout connector and not the
> octane adjustment plug (they look identical)
> IIRC, the spout circuit is a yellow wire w/green stripe.

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lugnut - 21 Jul 2006 20:01 GMT

>Are these connectors located on the distributor?
>
[quoted text clipped - 5 lines]
>
>Dave

It is normal for the timing to jump at idle. It is the ECM
changing the timing as it has been programmed based on a set
of inputs that in simple terms flip-flops back and forth
looking for a value that cannot be found as in the EGO
sensor. The ECM wants an ideal number but the sensor(s)
cannot/will not provide it. For instance, the ECM may be
looking for a value of 0.5vdc. The sensor(s) is such that it
flip-flops between 0.4-0.6vdc. This keeps the system
constantly tuning itself for optimum efficiency. In some
cases, if the ECM has detected a hard fault such as a value
that is not changing properly or within a designated range,
it will go into limp mode where the timing will only change
according to a predetermined failsafe table of parameters.
When you pull the SPOUT connector located over near the
cruise control unit on the left fender liner it will be rock
solid. Your 4.0 does not have a chain. It has timing gears
which rarely fail. There are better explainations but, they
are going to get much more technical if you are ready for an
automotive engineering lesson. Someone here will probably
be able to provide more than you ever wanted to know.

The 4.9L six may be one of the most bulletproof engines
ever produced even if it's performance is not up to the
demands of many drivers. After having several of them over
the years, I went to the V8's about 15 years ago when they
started raising the interstate speed limits. I find the
5.0L gets both better performance and fuel mileage at the
highter highway speeds.

Lugnut

>> Base timing on all EEC-IV distributor ignition systems is 10*
>> BTDC.
>>
>> Make sure that you disconnect the spout connector and not the
>> octane adjustment plug (they look identical)
>> IIRC, the spout circuit is a yellow wire w/green stripe.

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aarcuda69062 - 21 Jul 2006 20:37 GMT

In article
<1153505943.323769.53350@p79g2000cwp.googlegroups.com>,

> Are these connectors located on the distributor?

No. They are/have been located in various parts of the engine
control harness, though often very near the distributor or
ignition module if remote mounted.

> Also, currently the timing seems to jump a little, kind of like there
> is a loose timing chain.
> Just a brief bleep of 5-7 degrees. What would cause this?

Failing stator, failing ignition module, failing PCM, crossfire
between ignition wires, distributor cap carbon tracking/damp cap,
but if you haven't pulled the spout connector, it's meaningless
unless you think it relates to a specific symptom or problem.
It's not a loose timing chain since the 4.9 uses gear on gear to
drive the camshaft.

> thanks again

My pleasure.

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dave - 22 Jul 2006 02:00 GMT

You pretty much hit the nail on the head with your information!!
The timing is right on spec with the connector disconnected.
It looks like I have a high voltage leak in the distributer as I
getting the jump in timing with rouge pulses looking like its a cross
fire from another terminal on the cap.

I'll look into it in the morning.

Thanks!!

Dave

> In article
> <1153505943.323769.53350@p79g2000cwp.googlegroups.com>,
[quoted text clipped - 19 lines]
>
> My pleasure.

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