Misfire on 2 and 6, occurred at hiway speeds, limped it home now fails to start. Removed both o2 sensors, no start, swapped coils no start. Weak injector pulse, pull plugs on bank 2 after a few no start cranking, plugs look dry. Can smell fuel, fuel pressure 50 psi at rail.

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2004 S-Type 4.2 (added by GGG)

 

Gonna perform a compression test next to verify engine condition. Tracing injector circuits next with load testing. Coils look ok and no oil in plug holes. Plug gaps seem to be around .050 to .055. MAF sensor looks ok, blew out with air to make sure no bug wedged in there.

 

Welcome to the forums Randys_Jag,

I've moved your question from General Tech Help to S-Type forum. This is the place to post technical questions about your model.

Please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some information about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice about posting to the forum.

Graham

 

Curious as to why you removed the O2 sensors? You're not helping it start.

Also, why you'd swap coils around in a no-start?

Check the battery / power thoroughly.

When was the fuel filter last changed?

 

Removing upstream o2 sensors on a no start illuminates exhaust system as a problem.
As previously stated, misfire on 2 and 6, swapping coils tests to see if misfire jumps to different cylinders..
Changed fuel filter last year, under 6k miles ago.
Gonna hook manual fuel gauge to fuel rail tomorrow to verify correct pressure and volume and fuel rail pressure sensor reading.
checking for correct voltage and grounds at injectors tomorrow also.
Dry plugs after extended cranking and testing along with noid light flashing dimly indicates dropping voltage while cranking.
Lincoln LS vehicles had coils shorting out and zapping the pcm and at the same time blowing up the coils.. didn't see that here..
Expect fuel issue due to dropping voltage to injectors while cranking. Possibly a ground issue due to more then one cylinder being dry and all injectors share the same ground circuit. Sharing my diag results and a seasoned Jaguar tech would know of a common issue with vehicle.

 

Where did you find that?

Your car's PCM electrics etc have essentially nothing in common with the LS.

 

+1 on checking battery voltage across the terminals with the ignition in the OFF position. Use a voltmeter to determine the voltage; it should be a minimum of 12.6 volts.

Use a smart phone with the Torque app to communicate with the PCM through the OBD port via a Bluetooth interface. Fuel pressure should be around 3 bar with the ignition ON prior to engaging the starter motor.

 

If you can't see the immense similarities between the 04 Jaguar and the 04 Lincoln LS you may want to get some glasses. The drive trains are SO similar in many many ways. Some of the issues the LS was having in the field were repaired with Jaguar parts given to me directly by Ford engineers.
. As far as removing, not disconnecting, the upstream o2 sensors. If the exhaust is restricted enough to almost totally kill any engine performance , by removing the sensors and testing, opens the exhaust up enough to allow the engine to run. If engine still fails to perform or run, reinstall sensors and move forward in diagnosis. Simple test easy to do, rules exhaust out as the problem.

 

That avoids what I actually posted and you are in serious danger of misleading others and for all I know yourself too.

The LS and 4.0 S-Type have plenty in common but your car is a 4.2 - and the PCM and associated electrics etc are dramatically different.

 

Obviously common sense isn't a strong point where your from. I think I can figure this puzzle out on my own.

 

Not sure who this is responding on my concern, but dude, you need to get a life and maybe enroll in an auto class at your local college so you know something about mechanics.

 

@Randys_Jag, what is the battery voltage across the terminals with the ignition in the OFF position when checked with a voltmeter?

Use a smart phone with the Torque app to communicate with the PCM through the OBD port via a Bluetooth interface. Fuel pressure should be around 3 bar with the ignition ON prior to engaging the starter motor.

 

*you're

Also, you ended a sentence with a preposition.

Moderators, I'll save you the trouble and put myself in the timeout corner.

 

you thinking the misfires killed the cats? Do a quick compression tests with the o2 sensors in and out.

weird u could drive home but now wont stop. Almost seems like fuel pump was going and now its gone. So definitely check fuel pressure w gauge if theres a port to connect to.

can you get gas out the valve thingy?

 

The AJ33 and AJ34 engines do not have a schrader valve on the engine fuel rail.

 

I'm a little confused about a plugged exhaust system causing a no-start. I could see this causing low power and/or rough running. But even if plugged solid, I'd expect the engine to run briefly at idle before struggling and then stalling or backfiring.

 

I agree. I would think it would at least pop off and die as the exhaust stroke tries to push out spent gasses but he brought it up so I suggested a way of finding it. Ive never had that condition so I really don’t know if its likely or what the engine does with a blocked exhaust. I do know that if the exhaust is too small that you have no power on the top end but that’s about it from my knowledge on block exhausts

 

You'd wonder why someone would join a forum and ask for help then make an effort to alienate those who are helping.
Takes all sorts I suppose.