92 300CE Problem; starting and running - PeachParts Mercedes-Benz Forum

blueeagle289 · #1 07-01-2010, 02:00 PM

My 92 300CE is affected negatively by moisture. After a hard rain, it may be difficult or impossible to start, and then after starting -- if there has been a recent rain, it may start to run rough and then stall after reaching normal operating temps.

What connections or unit can cause these failures, which are linked to wet conditions only?

Thanks for any ideas or solutions. Ben Carter

mbdoc · #2 07-06-2010, 08:15 AM

Ignition issues including; cap, rotor, wires, & coil are the most common problems under those conditions.

blueeagle289 · #3 07-06-2010, 09:04 AM

Thanks for the tip regarding coil and wires etc; I will recheck these areas more thoroughly.

Ben Carter

rocky raccoon · #4 07-06-2010, 01:46 PM

problem with damp starting and running issues is a cracked distributor cap. May be very hard to see. Look carefully and also look for carbon tracking inside the cap.

blueeagle289 · #5 07-06-2010, 02:51 PM

I think I have a solid state electronic ignition, but if there is a distributor cap -- where is it on the car? I know there are several electronic modules just behind the battery, but which one controls the spark -- The Engine control module, or another one?

Thanks for the help ..... Ben Carter

Jer · #6 07-06-2010, 04:12 PM

All 103 engines have distributors. The distributor is at the front of the engine behind a black plastic cover. Very easy to replace. The KE Jetronic fuel injection control is one of the boxes you see behind the battery. The EZL ignition control is a flat module on the driver wheelhouse. The ignition timing is controlled electronically via this module. That's the only "solid state" part of the ignition system.

blueeagle289 · #7 07-06-2010, 07:17 PM

This is my quandary; I cannot figure out where the electronic ignition element or module is.

My engine on the 92 300CE is a dual OH cam engine and may have a totally different ignition system from the 103 engine.

Where is the distributor on the 104? or where is the electronic ignition module?

Thanks for all the help ..... Ben Carter

Jer · #8 07-06-2010, 07:47 PM

In the case of engine 104.980, the distributor is on the exhaust camshaft. The early 104 engines used distributors and KE fuel injection until HFM and LH Jetronic came out, at which point the ignition went to coil packs. The EZL module, as far as I know, is still mounted on the driver wheelhouse like on the 103.

blueeagle289 · #9 07-07-2010, 07:28 AM

Where is the Distributor physically, looking down on the engine (104) looking at it from the front ?? I have no idea where the exhaust cam shaft is on that engine and need a better locational instruction to find it. The engine does not have coil packs like my ML320.

I need more specific help to locate this module, or the electronic ignition module if there is one. Thanks again.

Ben Carter

Jer · #10 07-07-2010, 10:11 AM

The exhaust camshaft is on the left side of the engine, the side with the exhaust manifolds. The distributor is covered by a black plastic cover at the front of the engine, between the engine and the fan. The exhaust camshaft drives the rotor on the distributor. See the attached PDF for the location of the EZL module N1/3.

Ferdman · #11 07-07-2010, 06:46 PM

Ben, recommend replacing the distributor cap, distributor cap O-ring seal, distributor rotor, ignition wires, spark plugs and the coil. I would go with Bosch cap, Bosch rotor, Bosch coil, Bosch F8DC4 spark plugs and Beru ignition wires. Use a light coating of anti-seize compound on the spark plug threads and torque properly. Apply dielectric grease to the ignition wire boots to facilitate future removal from the spark plugs and the distributor cap terminals.

The ignition control module (EZL module) is mounted on the driver's side inner fender. Infrequent maintenance/replacement of the ignition components mentioned above can result in failure of the ignition control module. A new one costs around $2,500 ... so you want to avoid that possibility.

blueeagle289 · #12 07-08-2010, 02:14 PM

I have the EZL module on the driver's side inner fender and modules behind the battery which include the "engine controller" and the "injection system module" (in addition to the EZL). Also, the OVP unit is located there and at least one other subsystem/connector of considerable size.

I need to know exactly where I might have a connection problem that appears when damp or when the car reaches operating temperature. This is interfering with starting and running both. Does anyone have a thought about this?

Ben Carter

slk230red · #13 07-08-2010, 02:30 PM

Quote:

Originally Posted by blueeagle289

I have the EZL module on the driver's side inner fender and modules behind the battery which include the "engine controller" and the "injection system module" (in addition to the EZL). Also, the OVP unit is located there and at least one other subsystem/connector of considerable size.

I need to know exactly where I might have a connection problem that appears when damp or when the car reaches operating temperature. This is interfering with starting and running both. Does anyone have a thought about this?

Ben Carter

Crankshaft Position Sensor that connects to the EZL.

Have you replaced the distributor cap and rotor yet?

blueeagle289 · #14 07-09-2010, 08:05 AM

I think the crank shaft position sensor could be my problem. I had the same difficulty with my 99 ML 320 and just replaced that.

Where on my 104 engine is the crank shaft position sensor?

slk230red · #15 07-09-2010, 09:41 AM

Quote:

Originally Posted by blueeagle289

I think the crank shaft position sensor could be my problem. I had the same difficulty with my 99 ML 320 and just replaced that.

Where on my 104 engine is the crank shaft position sensor?

If you don't know where it is, try tracing it by starting at the Ignition Control Module.