2004 Disco Misfire Problem

[Menace2U]

37K miles. I am original owner. Throws 0300, 0305, 0308 so engine is regsitering mis-fires specific to #5 and #8 cylinders. SES light is on and blinks. Can idle and drive but with loss of power. Idle is rough-ish. Symptoms started last week about 10-15 miles after I filled up tank with supposedly 93 octane at a gas station I normally do not use. I had driven the car the day before for 5 hours straight at 65 mph with no issues. Drove fine before and right after fill-up then started throwing the SES light with noticeable loss of power.

Since 5 and 8 are served by same coil, I assumed bad wire/plug. I did the night test and saw sparking from the #8 wire. Put test light on the plug and saw very weak light on cylinders 5 and 8 compared to other cylinders so was pretty sure its plugs/wires.

So, new champion plugs in there now and new Magnecor 8mm wires. Since I removed intake, I decided to put 2 new LR coils in there also along with new intake gasket. Did this all yesterday and fired it back up to get the exact same symptoms and throwing the same codes. Put test light on 5 and 8 and same weak spark.

Let me repeat, as of yesterday, brand new champion plugs, brand new Magnecor 8mm wires (properly routed and wired), brand new OEM coil packs (both of them - came in LR box so they are not aftermkt).

Vacuum is steady at 18 and does not vary at all at idle (so likely not a valve issue). Had battery unplugged for 5+ hours during intake removal so that should have cleared the ECU. Have cleared the codes many times via OBDII scanner but they come back as soon as I try and rev about 1500 rpm. SES light flashes and then stays lit until I rev it and then it flashes and will continue flashing if I drive it any short distance.

Only thing else that I can think of that is common to both 5 and 8 is the ECU ignition signal. But I don't think I can test that.

Is it time for the dealer? I still have warranty but knew the dealer would want money for the new plugs/wires (OEM wires alone are over $200 from the stealer) and I wanted magnecors in there so it was cheaper to buy those parts and do myself. At this point, I am not sure what else to check.

Any ideas?


AndrewT

[Rovin4life]

Andrew you completely screwed yourself.

LR warrantee pays for everything whilst in warrantee. I mean everything. If we feel it needs plugs and wires and new gaskets we put those on at no cost to you.

seriously dude you wasted a shit load of time. if you are completely out by time then you still screwed yourself by putting the magnacors on they are going to start ripping those parts out and installing everything land rover to make sure that you didnt cause any problems. something you will have to pay yourself.

five bucks says you installed them backwards as well. five and eight that is. the only other thing is to check to see if they are secured tightly.

looking from the top and working the way down from the passenger side it goes as follows.

8 5 6 1
2 3 4 7


oh and by the way you didnt need wires or plugs. you wasted a shit load of money by listening to guys who dont do this for a living. I do. unless its one wire number or alot of misfires on more then five wires then no you dont need wires or plugs.

[Menace2U]

Wires are not reversed. Same symptoms now as before. I did originally only replace #8 wire and #8 plug - had same issue. So I then also replaced #5 wire and #5 plug - had same issue.

So, I assumed bad coil. I have the coil diagram and used it and triple-checked while installing new wires. Other people helped and we are checked the work. Its doing the same thing it did before. I decided on Magnecor's as I was taking the intake off and it made sense to do them at the same time. Plugs are simple and cheap - so I don't see that as a waste either.

If they replace wires - fine - I'll take the Magnecor's back. Don't see how stock wire original, stock (LR OEM) #8/5 wire replacement, and then magnecor replacement would all have same issue if its the wire alone.

Sorry - I don't think this is wasting my time. I have seen very shotty dealer work and prefer to do work I can myslef as long as its not too much money and something that I feel comfortable doing. For plugs, wires, coils - this is fairly simple stuff so nothing is wasted IMHO. I worked on my friend's disco after mine and found his #5 wire pinched under the intake from prior dealer service. We had to loosen the intake to get it out - that was a failure just waiting to happen. So, when I see that kind of work - it re-inforced why DIY can be a good thing.

So - you posted about how I wasted time but have no other ideas on what might be wrong??? Its not crossed wires - that I know.

AndrewT

[Rovin4life]

Andrew you wasted time by not going to the dealer.

shotty or not you dont pay for it. plus any tech would have looked at both misfire 8 and five and said a coil without even wasting time on on the wires.

why, because on disco twos there is not ground to the body. instead it grounds thru the coil. hence 5 and eight are on the same coil and ground thru each other. Thats something we know from our training at land rover. Not something you will get off the internet unless someone like me gives out the information. You fell into the most laughable trap most DIYers fall into. Its the herd mentality. if one guy says it works then it must. Yet when professionals like me see the problems we shoot for the answer the first time. We dont use a parts shotgun like you used. we use our experience in cases like yours. Why cause when we screw up at the dealership we repair the vehicle again at no cost to your and we dont get paid for our screwup.

If I were you I would have brought it to the dealer got it diagnosed and then look at the job they did. If they made a mistake like getting a wire trapped then yes head right back to the dealer and get it repaired for free. Remember all of this for free. Hell chances are you could have gotten a rental care for free.

instead you wasted time, money and alot of head ache by diagnosing something yourself without the correct information dealers have.

when you do this for a living you have to be right. or else.

[Menace2U]

Rovin4life,

Did you even read my first post?? So far, you have posted nothing I didn't already know.

I had already diagnosed this as potential coil issue and replaced coil packs (both of them). Still have same issues.

I already knew that 5 and 8 share the same coil and they utilize the LR 'wasted' spark principle. I also know they share the same ECM ignition signal on pin8 in ECU Connector 5 (C0638).

This was a parts shotgun? WTF is that? I wheel this and don't have an issue buying some parts I can always use as spares if needed. Plugs and wires are always good spares to have when out on the trails so, if my originals were fine, I can use those as back-up. And it cost a little over $100. Good insurance if you ask me.

Who cares about shotty dealer work??? I do. Because its my truck. They do some half-assed work and then I deal with the issues later when it lasts 15K miles and I am out of warranty. Plus, you end up spending all your time driving to the dealer which is 45 mins for me each way - and then hassling with them on rental cars even if they agree to give one or hassle about if they will cover your truck because the coil is bad and you put in aftermarket floor mats that supposedly void your warranty. BTW - the other truck we worked on had more shotty dealer repairs than just the pinched plug wire. The SAI pipes behind intake plenum were just hanging there and unsecured as they were supposed to be. Also, the coil packs on the other truck were attached with one screw to the bracket and also dangling loose. Good dealer service there. Maybe those guys missed that day of training???

I'll use the dealer when needed. But the less the better.

So go read my first post and enlighten me with your LR-trained intellect. So far, I am less then impressed. The only thing you seem to know for sure is to take it to a dealer and hope for the best.

Thx for the bump though. Post something useful or don't post at all. I need input not criticism.

AndrewT

[roverthen]

Rovin4hood, you are a complete ass! Since you took the time to insult Andy, I am taking the time to shout this out and let you shine jackass.

Every advice you give starts or ends with taking it to a dealer or shop. You are a complete idiot. You truly sound like a mommy's boy. Haven't you heard of people wanting to fix something instead of taking it to someone else?!

Do I pretend to know it all? NO. I do however try and try until I succeed. One day when I am on an expedition, in a remote area, I will be able to get myself out of trouble with the knowledge I picked up.

In case you don't get it by now 'robbing for life', this is not about money, not about warrantee, not about being a mechanic. Get a clue. You should find some place where you will be praised for your stupid remarks and comments. I heard that the Honda Element Club is looking for people like you!


Andy, I applaud you for trying to solve your own problems, even if you do have warrantee. Most people on this site get that. Rovin for jackass doesn't. What the heck does this guy do exactly? He doesn't own a Land Rover.

[DiscoAmigo]

Try checking for a short circuit between the coil and ECU. Do you have a RAVE CD? Mine shows for the 5 and 8 cylinders--connector C0156 pin #1 (red wire) at the coil pack, and connector C0638 pin #8 (red wire) at the ECU. Good luck

[Menace2U]

Thx for the good suggestion DiscoAmigo. Yes - I have Rave CD and knew the pin# on connector 5 to the ECU. Did not see the reference to the coil connector pin # so I can check that link. Seems odd that there would be physical issue with the wire but can't hurt to check. Unless maybe that wire near the coil plug got brittle/worn from the engine heat.

Again - Thx for the good idea.

AndrewT

[rmuller]

Rovin4life -- This is a technical repair forum for do-it-yourself'ers ... if your advice is going to continue being 'go to the dealer', do not bother posting.

[Menace2U]

Originally Posted by DiscoAmigo

Try checking for a short circuit between the coil and ECU. Do you have a RAVE CD? Mine shows for the 5 and 8 cylinders--connector C0156 pin #1 (red wire) at the coil pack, and connector C0638 pin #8 (red wire) at the ECU. Good luck

Just checked. The wire has continuity so it looks like that is not the problem.

AndrewT

[Menace2U]

As best as I can tell, this is something to do with the ECU. Can't think of anything else to check as the obvious items have all been covered.

Called dealer this AM. They said to drive it over - will get a loaner car since 37.5K service is due. I told them SES light is on and flashing - are you sure I can drive it??? Asked five times. They said drive it over - no problem. I even told them what codes I pulled from OBDII scan - that its underpowered, and that I am likely dumping unburned fuel down the mis-firing cylinders right into the CATs. Drive it over they say. They then went on to tell me that steady SES is trouble but blinking SES is fine which is the opposite of what I thought to be true.

Anyway - I tried. Will see what they can find.

AndrewT

[rmuller]

Originally Posted by Menace2U

They then went on to tell me that steady SES is trouble but blinking SES is fine which is the opposite of what I thought to be true.

From the owners manual:

If ‘Service engine soon’ illuminates, and the
vehicle drives normally:
•Contact your Land Rover retailer to
schedule a service appointment at your
earliest convenience - YOU MAY STILL
DRIVE THE VEHICLE.

If ‘Service engine soon’ flashes and/or the
vehicle does not drive normally:
•Avoid high speeds and seek immediate
assistance from your Land Rover retailer.

You should be taking it to Paramus... this is just the beginning of the sign that you're dealing with idiots

[Menace2U]

Originally Posted by rmuller

You should be taking it to Paramus... this is just the beginning of the sign that you're dealing with idiots

Calling you now to discuss. Already talked to Abe. Looks like the way to go.

[Rovin4life]

[quote=roverthen]blah blah blah I dont do this for a living so if this doesnt work oh well. By the way jackass I do own a land rover. was going to buy another one but didnt feel like shopping around for another motor.

if you do this for a living working on cars its different. You have to fix the car or else dont get paid. Thats what I do. I work flatrate. And I have to fix the problem their is no dealer to save me. Maybe techline to give me some ideas but those guys are so new they absolutely suck. So I use what I got and diagnose the vehicle.

by the way Roverthen do you know any of the subtle differences in evap systems or secondary air or other little things on a disco two. Trust there are enough subtle thing things that can screw you up.


by the way heres a really scary thought, lots of shops are losing their top techs due to flatrate. As they cut times further and further our paychecks get less and less. Thats right the same guys you want working on your car make less and less each year. So they leave for greener pastures. Needless to say the replacements come from the domestics. Not bad but they arent educated in all things rover. Takes at least a year for a guy to be a well developed rover tech. And to top it off lots of jaguar land rover shops want to cross train guys. So they know a bit of both. But how well they really are is up in the air. personally I think it costs us everytime they misdiagnose because they arent familar with rover. Sure warrantee is fine cause its free but cash tickets are up in the air.
Trust me air suspension diag on RR is easy. But to a novice they can get sidetracked with the codes. Best way to diag one of those is clear the codes and soap it. But guys waste tons of time looking for codes.

oh and their are guys that do shotty and shitty work. usually they dont last long. but you feel the pain when they screw up royally.

[roverthen]

Originally Posted by Rovin4life

If you think I am an Asshole. So be it. I dont care one bit. I just fix Rovers. Dont run em. Dont play in em. I fix em. And if I dont fix em right. I get in trouble.

Remember this crap?

Originally Posted by Rovin4life

In case you don't get it by now 'robbing for life', this is not about money, not about warrantee, not about being a mechanic. Get a clue. You should find some place where you will be praised for your stupid remarks and comments. I heard that the Honda Element Club is looking for people like you!

Here it is again.

D-o y-o-u u-n-d-e-r-s-t-a-n-d ?

read it 50x more........and when you respond again with your usual rant I'll just repeat myself.