Hi,

Can anyone advise me, I got this car few months back (80,000km)and it drives lumpy whenI accelerate usually from 80km/hr-120km/hr. I always use 91 Octane fuel,than twice now I had the check engine light flash amber it stays for a day and disappears. The problem is every timeI take it in for a check-up the check engine disappears. Also it emits a horrible sulphuric rotten smell in the cabin.I am wondering if I can get it scanned using an OBD-II scanner first. I filled up at the pump yesterday and used a gas treatment additive & whenI went thru thecar wash yesterday which cleans the undercarriage also and asI drove off I it started jittering, but an hour later it was ok. Any suggestions what this could be?.

Thanks

 

Could you please be a little more descriptive with your concern than "lumpy"?
The check engine light...was it blinking then stayed solid?
V8 or V6?
Possibly at catalytic convertor problem.
Give up some more info and I will try to help.

 

Hello,

Thanks for the reply, This is a V6. Yes the amber check enginewas blinkingat first few times than went solid, a day later itwent away again. Sorry what I meant by lumpy is that the car ride is choppy and hesitant , whenshiftingup usually from 80km/hr up to 120. My apologies I just cant find the right word to explain,but it shifts up not smoothly at all and continues tohesitatewhen you give it gas. Its as if not getting enough fuel or air intake. I was thinking it could be the air cabin filter as it emits a rotten smell at times also.Iknow you dont have much to go by specially the way I have worded it. Any suggestions or advise is much appreciated. Also an approximate cost to fix the problem.

 

Hi mrhayat,

Dont apologies, its ok to use those words as thats why we called them Tech guys and not us Just try to delibrate more so Jagtech or other techies can try to solve your problem [sm=signs003.gif]

 

You are definately right. Thanks for the support Jaguarnaut

 

Well, the rotten smell with the type of hesitation sounds like you have a coil problem. If the Ignition coils cannot make the spark plug fire, the unburned fuel goes into the catalytic convertor and will eventuall give off that smell.
I would also check the breather hoses at the back of the intake. Spray some throttle cleaner down there and see if idle changes. If so, they are leaking.
Pull the silver cover that says Jaguar off from drivers (LHD) side and look at the coils. If they have green or yellow labels on them they are old coils, new ones have black labels on them. If that is the case, I would replace the coils and all the plugs as they are probably fuel soaked.
Hope this helps,
If you need any more direction as to where these items are located. Let us know.

 

What advice FJT do you have on taking the manifold off to replace the other set of coils? I am going to do it myself, but I have not heard of anyone doing so. I am going to replace the whole side since I will have access to change the one bad coil.

 

If you are going there, do yourself a favour. Get the upper and lower manifold gaskets. Also get the lower breather hose and change it out while you are in there. It is a 13.00 part and stupid to not do it while you have manifold off.
I will post the procedure in the general tech forums later on tonight. It is not hard, but be careful to not overtighten anything or to drop bolts down the intake!

 

Ok. I'll check back later. Thanks!

 

Hi FJT,

Can you also please advise me with this car just recently the engine fan turns on after a 15 min drive, even though the tempraturegauge has always been midway. Also it takes 20 mins or so to get the fan torun the heater warm air.

 

I would say your expansion tank is leaking. In front of drivers side windshield where you add coolant, this is the tank. They crack pretty consistently.

See if it looks low. If so, fill it up and run the car. see if it starts to leak out underneath drivers side behind front wheel.

 

I will check definately.,Thanks FJT

 

I'm intrigued by the 91 Octane fuel rating.

All S-Types delivered in Australia have a 95 Octane sticker on the inside of the filler cap.

The lower octane could cause it to drive "lumpy".

Regards

 

Different ECM software combats the Octane level. Different parts of the US have different Octane level for premium. Some are 91, some 93 and I have seen a couple that were 95. Wyoming I think?

Anyway, I understand what you are saying, but premium grade fuel is what is recommended. 87 Octane.....now that would be an issue.
You are lucky you get that quality of fuel in Australia. Most of the fuel flaps on Jags in the US have the 91 octane rating.