No Spark on '93 320CE
 

Need some help here please....

Car is refusing to start, despite turning over same as always.

Haven't got very far, but confirmed there's no spark.

I'm suspicious of the immobiliser, because of the quality of the installation wiring, but diagrams for these are dealer only. I'm trying to trace 12V power from the ignition switch to the Engine Management Unit, but I can't see a wire on the wiring diagram that goes between them.......

Anyone know if you can still read the fault Codes with a non-firing engine? I'd appreciate some advicce on reading the codes too, I understand this model is not an OBD type?

Thanks for "listening".

How have you confirmed no spark? From the coil, or did you take a plug wire off? Those EZL systems are pretty reliable, so you might have a tune problem if you are loosing spark. The ignition module isn't something that goes out much. I would check the coil, and the crank sensor. The crank sensor it eh green single wire plugging into the ignition module. If you have an ohm meter, you can ohm it out, though not a very reliable test, but it is something you can do to rule it out. I believe it should be between 600 and 1200 ohms. You have to check the ohms by pulling it off, and put one terminal of the ohm meter to the center poll, and the other on the side.

By the way, the EZL (ignition system) is pretty much separate from the ECM. Post what happened to have the car before you the no start problem.
Is your car a federal, or a California model? You can read codes, it is very easy. I will check the post later
GVB

That chassis should not be EZL, but rather HFM/SFI... which means you want to check your OVP relay.
Do a search on it and see if you have the old part#.
If so, change it and also look for a blown fuse on top of the relay.
The OVP is power feed for ignition and fuel injection on HFM systems

It is an EZL system, in 93 they did not have what you are refering to an EFI system. It is a CIS-E system with an EZL ignition system.

My bad, CE, sorry

No, it is an HFM system, exactly the same from 1993 - 1995. I should know. I had one.

Sorry , but 104.992 engine was full electronic with distributorless ignition . waste spark ignition w/3 coils /over and MAF ....with OVP power feed to ECU.

For Original poster, here is the part you will need if you find the OVP to be the cause.

http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1M30LAGSC1T40R0NIU&year=1993&make=MB&model=300-CE-003&category=P&part=Overload+Relay

Got mixed up w/ model,
some did, some didn't

GVB

You are wrong - the 320 was only ever fully electronic.

Cars are a technical subject - lets be technical - to all the guys/gals out there, if technical is not your thing, then I suggest you don't mess - a survey I saw somewhere suggested that 30% of all car faults was because of ill prepared persons messing with cars.

Regards

I do not believe GVB falls into that category.
He stated his model error and if you read any of his postings, you will see he is familiar with Benz workings.

Exactly.

After reading most of his posts, I'm willing to bet he works as a Mercedes technician, either at a dealer or an independent.

Well, if you want my opinion, it is more like 70% of the time, especially when a mechanic not familiar with Benz works on a Benz. You would be surprised how many different Benz are out there, one year can vary as much as 3 different systems. In the late 90's they started to standardize though. Has gotten much better.

I joined this site for information on WVO and such, but reading all the posts I just had to jump in a give some advise. I have been a Mercedes Tech for about 15 years, all independant. You ask me, the dealer techs are way too narrow minded when it comes to diagnosing.