Discovery II 2000. 13K since a rebuilt engine, everything replaced. Did not (my error) replace the coil packs, did so yesterday. New CPS, plugs, wires, upstream O2 sensors, now coil packs. Done with the help of my indy mechanic who is well versed in LR/British Leyland as he is the top shop to go to for your MG needs in my area. Truck has been absolutely great until.....

Went back this week as i was getting the P0304 code under normal acceleration, goes into 3rd gear, you can feel something like a missing plug, SES flashes, back off the throttle the engine smooths out and the SES on. If I accelerate slightly, truck will miss (used to call that "lugging" the engine) SES flashes and goes solid on if I back off and cruise about 40 mph. Will miss and buck crusing at 55 mph or higher.

We replaced the coil packs (still plan on getting Gerry's relocation kit later this fall), plugs and wires again, finishing yesterday, and drove home from his shop just fine, hot day, engine up to temp (188 degrees), no miss, no light. Purposely pushed it to try and throw a code, nothing happened. All set. YEAH!

But, (and that's a big BUT!), went out this morning to run a few errands before coming home to do the ignition key cylinder fix with the cylinder from Atlantic British, and Voila', the SES light is happily flashing at me and now causing the miss in 2nd gear and higher!!

My indy mechanic does not have the LR specific electronic diagnostic equipment, I am reading codes with a on board Scangage II. There is another indy mechanic who is a good friend, but prices are much higher. He has all the latest/greatest diagnostic equipment (I use him to diagnose problems with my ACE system, spot on ).

So my question is, will the LR diagnostic equipment tell me what is going on? I've just about tried everything that I can do, or really pay through the nose and go to the LR dealer in my town?

I know I'd have to put on a tie and wash the Rover for them to agree to see me, but hey I'm running out of options. The truck is my daily driver, looks great, wonderful condition, great engine, everything works, except for the $(#* SES light and P0304.

I ask the collective for any ideas.

Thanks as always!

 

From D2 WM:
LR test equip will say the same.
......

 

Try swapping the #4 and #3 wires and see if the misfire follows. My guess is it's the plug or the wire. They can be damaged when installed.

 

More times than not, this has been my finds while following in someone elses footsteps.

Did a... "runs like crap, since I tuned it up" ...redo on a friends pickup once. Three spark plug porcelains were broken and one wire was not fully seated on coil pack.

Usually, if a code developes after working in a particular area of the engine...something went together wrong. Go directly to the area of the miss, check plug, wire connections at both ends (or change wire as suggested) and such.

Brian.

 

Your temperature ilooks normal but are you having coolant loss and seems like over presurized cooling system?

 

Yes, I am losing about 4 oz every 7-8 days. I'm rather **** about stuff, so I know how much I add (I measure it). The overflow tank shows a loss, I open the cap, get a "whoosh" and the level rises in the tank. Then takes about 4 oz to bring it uncapped back up the the "cold" arrow line. Always check it in the morning after an overnight cooldown.

What am I to look for now, LR03NJ?

Alan

 

Do the kit later get a Head Gasket kit. If this thing happens, you might observe that you have white smoke upon start, or not. Loosen the cap and drive normal, following day when you start engine you will notice no white smoke upon start. (only if those things are happening) meaning some of the coolant goes in the cylinder over night because of pressure. You might not over heat coz cooling system is ok but overnight, the remaining pressure goes through the gap in the head gasket. Your SES will blink once in a while because of moisture inside cylinder which allows it to misfire.
Might be the case but this is just a theory I was thinking.

 

Gerry,

Didn't realize that "LR03NJ" was you. Trying to diagnose from my office at school. I have no white smoke at all, no smell from the exhaust, just 4 oz of coolant loss about a week, as many times I'll check it after about 3-4 weeks, and it will take about 12-16 oz to bring it back up. It will be down in the tank, then un-pressurized and the level moves up when I unscrew the cap, add the coolant, then back on with the cap.

Interestingly enough, it hadn't done this for about 2 months, then suddenly, right back at it. I had my indy mechanic change the upstream 02 sensors about 2 weeks ago and the miss and the codes went away, for about 2 weeks, then its back again.

I was thinking spark, since my coil packs have 100K on them since the last time I replaced them, I replaced them as well.

I will also isolate the injector by moving it from one cylinder to another, trade places, and see if the problem moves.

Really don't want to pull the head again but will if needed. Tired of throwing parts/$$ at it. It's really a great truck.

Alan

 

Cool, then it could only be the coil packs, cracked or just need replacement. With the injector, you should get some injector related codes somehow even when the O rings are worn. Then try injector cleaner for the time being. Then its relocation time! LOL!

 

Coil packs replaced last Friday, so perhaps the injector will show the issue. Going to the indy shop after school today. Will let you know the possible problems.