I have a 1993 XJ6. I am getting no spark off the coil. The engine cranks. I get a FAIL reading on the VCM nothing else. I have replaced the Crank Sensor, Coil and Distributor cap and ICM. There is power to the coil. I only have 70,000 miles on this vehicle so I am assuming that all the parts are original (I bought it used). I feel like there is a battery drain somewhere because the battery goes flat very quickly. I have tried getting spark by jumping, no luck. Anyone have any ideas what could be wrong? I have an adapter for the OBD 1 port but the modern scanners do not power up to get a reading. HELP!

 

Your car is about a decade too early for this section of the forum!!

bob

 

Can you direct me to the right thread?

 

It's the xj40 section in "classics" . There are a lot or causes for no spark. Start with a good visual on all grounds and connections. I have had center button in distributor cap get stuck up out of reach of the rotor. Good luck

 

Hi William,

Welcome to the Jaguar Forums! It's great to have you with us!

I have moved your post from the forum for the X350 to the forum for the XJ40, which is the Jaguar factory project code for your 1993 XJ6.

The first thing I would suggest you check is that the tachometer is reading about 200 rpm while cranking the engine. If it reads 0 rpm, there is either a problem with the Crankshaft Position Sensor (CPS) or its wiring. It is not uncommon for the electrical connector to become fouled with oil and grunge, or for one of the pins to back out of the connector while the new CPS connector is being pushed into place.

The next think I would suggest checking is the battery voltage while cranking. If it sags much below 11 volts while cranking, the Engine Control Module (ECM) will not trigger the ignition to fire. Low battery voltage while cranking is one of the most common causes of cranks-but-won't-start.

To add to Jerry's suggestion, it is important that certain grounds are clean and free of corrosion or contamination. The most important ones are the two on the intake manifold, the one on the firewall behind the cylinder head (these three are referenced by the Engine Management System (EMS)), and both ends of the engine ground strap (which is the ground path for spark).

Please keep us informed, and when you get a chance please visit the New Member Area - Intro a MUST and post a required introduction so we can learn something about you and your Jaguar and give you a proper welcome.

Cheers,

Don

 

Did you change the rotor as well as the distributor cap? That is often the culprit.

Larry