Hi all –

I’ve got a 2003 S-Type R with 89,970 miles

I’m new to this forum, and a new Jag owner. I’d stumbled into this car via a friend who was moving from WA, to New Jersey. She purchased the car in 05 with about 40K miles on it. Since that time, she’d lost her job, and didn’t have the funds to deal with the car properly. Other than a few “jiffy-lubes” the car has almost ZERO maintenance.

With that, the car is still in almost PERFECT shape. It started running rough about 4 months ago – and she parked it. Not having the money to take it to a real Jag repair guy, she had a “guy she met at Chevron” look at it. I later learned he was her “mechanic”, the same one who told her the engine was dead.

I offered to help her out, and deal with car as she was moving. At this time, I’ve got ZERO money it. last we spoke, she wants a few thousand to be rid of it.

I got to her place expecting to see a disaster. To my surprise the car seemed totaly fine, apart from a rough idle, and the check engine light. It runs smooth as glass at speed.

I get code P0304, Cylinder 4 misfire.

Not a big shocker, considering the lack of maintenance.

I was thinking of hitting all the obvious stuff first.

· Oil Change
· New Fuel Filter
· New Plugs
· Coil Pack(s)?

Is there anything else I should check off the list – anything obvious that I should do…. I’m thinking simple stuff that I might get lucky and just fix the problem by changing / fixing / replacing. My next guess would be to check for a vacuum leak – but that’s me guessing…. Truth is I have no clue, I’m just thinking take care of the obvious.

Thanks for any help / suggestions!
Dave

 

Plugs would be due at 100K so now would be easy to justify. But, chances are it's a coil. Not guaranteed to be #4 but again chances are that it is.

To avoid spending much, you could check the fuel trims at idle and at 2500rpm (in Park will do). You'd need a cheap OBD tool like the elm327 or any hand held that does live data. Good tools to own for any modern car.

You could also sanity check the O2 sensors. If they're giving good data and the trims are OK, about all that's obviously wrong will be that misfire. OK, that's an IF but you're in for hardly any money.

The engines are good but like oil changes (5W30 - any brand). Also, the fuel filter is likely due and they're very cheap. Air filter, same.

It could be an air leak but the OBD readings will show it if so and it's not likely you'd have just one code. (Possible.)

If you replace parts, genuine fuel, oil & air filters are not badly priced but there are cheaper.
Do not use the wrong plugs or coils, whatever you do unless someone like Brutal tells you to. I wouldn't replace them all right now (they're not cheap), as I'd be looking to get it running better. Then if I were keeping the car I'd probably do them all.

Wow, I have a relative somewhere near you, amazing!

 

yup - good call on the elm327. I notice you'd recommended that same tool in another thread so I got one on the way via eBay

I'll check the codes at 2500 once the reader arrives - and go from there.

From the limited amount of web surfing I've done, it seem very likely that its coil / spark related. But it’s the original fuel filter.... holy cow!

thanks again for the help!
Dave

 

I should also - mention....

At this point, I'm intending to keep the car. Its a VERY nice ride! This one is particularly clean.

I'm not sure what trim levels the -R shipped in, but this one is LOADED. I don’t think there is anything else they could have added.

This is why I'm thinking just swap out the obvious stuff.... kinda should be done regardless. Plus, if I do sell it (not likely), I'd want to be able to say it runs good.... for real.

 

I had the same code and symptoms in my '02 3.0 about 50k miles ago. Changing out the coil packs and plugs took care of it right away. Sounds like you got a steal!

If you look, you can find the Motorcraft coil packs you need on eBay for about $15-20 each IIRC. I would just look at the numbers on those you can see easily and order them. Once you have them all in hand, replace them all. Getting to some of them is a bear... but it can all be done on a Saturday.

 

Not an "R" nor even V-8, but same time/mileage as yours. Good checklist to refer to:

https://www.jaguarforums.com/forum/s...ad.php?t=49309

Too bad you're so far from the NC/SC border...there's a coolant line or something on those "R's" that Rick's been itching to have a go at!!!

 

Mine did the same thing with bad coils. At idle it felt like I had a bunch of kids kicking my car, but at speed it was fine. A couple coils later and it is back to 100%.

 

Welcome Dave! I traded a 2009 370Z for my R, and am quite happy with her, well that and no car payment! I see you have a C172, I am a controller as Cascade Approach and Eugene Tower. If you ever are down my way stop in and I'll give you a tour! Let's see some pics too.

 

Do be aware that the coils and plugs on the STR are NOT those on the V6 or the 4.0 V8. Plugs are Denso. Coils I don't know, never needed one so far. Also, I think they changed to yet another kind in about 2005/6 (probably 2006).

 

I agree!

 

I Got the ELM ODBII reader on the way. Picked up a set of spark plugs, fuel filter, fuel filter line removal tool, air filter etc.

I was going to get the coil packs as well, but ran into a problem at the auto-parts store. There were 2 different part #s shown as OEM. One with 4 prongs, one with 2. I had the guy spin the screen around to show me the photo. They looked almost the same - I and saw the details on the screen showing the 2 different parts. I was a little surprised the computer showed 2 options for the type R

Anyone know what part number is correct?

They wanted $70 each. Might need to look into the eBay option, though sometimes eBay parts quality makes me nervous


Thanks!
Dave

 

Based on this thread it sounds like there are at least two versions: https://www.jaguarforums.com/forum/s...ad.php?t=11506

 

Looks like these guys have them for about $44 a piece.

http://www.oemonlineparts.com/partlo...layCatalogid=0

 

You want the 4 prongers. And Advance has them for ~$50 each

http://shop.advanceautoparts.com/1/1...art-e1019.html

 

I guess I should have done some additional searching before asking....

Thanks for the links! I'll get them on the way

 

Order online from Advance and they usually have a discount. Also, search Amazon.com for the same part number, I was surprised how many auto parts are on there. A few thousand? Good deal!

 

Ya Advance always has some kind of deal of a % or $ off.

 

Well... after weeks and weeks and weeks of waiting I finally got in the coil pack(s) from back order. Even then, they didn’t have a complete set, so I only ended up with one.

Since I only had one, I swapped out the coil pack and spark plug in the suspect cylinder, #4.

My understanding is the cylinder order (but not the firing order) is.

CAT
4 8
3 7
2 6
1 5
FAN

I swapped out #4, passenger side, closest to the firewall.

It was a very easy change, only took about 5 min. Attached in a photo of the plug that came out. I don’t know much about plugs, but this one looks nasty... I belive it is the original plug. It was dry, there was no evidence of any kind moisture on any of the parts.

With the coil and plug swapped, I expected some change.... I got nothing. Its running EXACTLY the same. Maybe I swapped out the wrong cylinder? It’s still super rough at idle, smooth’s out as I give it gas (unless I pound it, then I get restricted performance until I lift off the gas). Check engine light is still on. Still the same code. P0303 Cylinder 4 misfire.

I got the ELM reader off EBAY, but it was DOA, so I ordered a new (better one) from a local vendor. Once I have that I will capture the fuel trim data at 2500 and reset the codes.

Any other obvious stuff I should check?

thanks
Dave

 

You have the wrong layout of the cylinders

This has been covered so many times but hey one more......

front
2 1
4 3
6 5
8 7
rear

It's in the Vehicle Specifications, well worth getting from here, and in JTIS - ditto.

 

hmmm... I guess I got the order wrong. I'd done some research via the forum and found this link:
Automotive Forums .com Car Chat - View Single Post - Misfiring?

this is what I thought was correct.... I'll check it again and see if there is any difference

thanks!
Dave