'90 caravan elec. problem

[buffaloroad]

It is official: if you turn the key on and the check engine light doesn't come on then you have no spark....sad to say the van is dead again. Can I jump to the ignition module (wherever that is) and get it going again???? Can I jump anything and get spark, maybe bypass the auto shutdown???

[yogi_123rd]

To give you a clue:

The 3.0L has a hall effect distributor.
The 3.3L has an electronic ignition and camshaft.

Basic Computer controlled inition systems:

In the modern engine, the spark to each cylinder is controlled bythe computer. All systems use a Crankshaft Position Sensor (CPS). This is used as a timing signal for number one cylinder and used in determining the engine speed (rpms). If this sensor fails, no spark.

A second timing signal is generated from either a Hall Effect distributor or a Camshaft Position Sensor in an electronic ignitions system. The computer must see both signals in order to send a signal to the coil (or coil pack module) in order to send spark to the cyclinder.

Typically in this case, the computer sets a catch-all malfunction code of "no timing" when there is a problem in either sensor.

A Hall Effect distributor has a lobes with magnetized tips instead of cam lobes. As the lobes pass a stationary magnetic pickup sensor, a timing signal is produced that the computer senses. These systems typically use a single high voltage coil for all cylinders.

With an electronic ignition module, the timing signal usually comes from a camshaft position sensor. These systems typically have a multi coil pack in the ignition unit. Each coil in the pack is wired to two opposing cylinders (one on a compression stroke, the opposing one on an exhaust stroke). In many electronic ignition systems, a single computer signal is used to run these two cyclinders. When the coil discharges, electricity will take the path of least resistance. The cylinder on the upstroke with the compressed air-fuel mixture fires rather than the cyclinder on the upstroke exhaust cycle.

The MIL light that is not coming on sounds like a burnt out bulb. To check for a burnt bulb, turn your ignition on. All your indicator lights should light up.

[buffaloroad]

Thanks, but I've got the 2.5 and I've already replaced the coil, the dist. inductor (I'll call it that...), and all the sensors except the fuel pressure and the fuel inj. (single point)....everything else is new....at this point I just want to jump past whatever is wrong and get it running....it is a $500 rig with 230k on it, I can't spend $300 on it......the dome lights stopped working a while ago and I see that that fuse is blown.That fuse also powers something to do with the ignition, so now I want to by pass the short and just wire to the ignition, whatever and wherever that is and see if it will run.....