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Jaguar Engine Interferes with iPhone4 Ack!

OK. This is just a weird problem. Here’s the background…

I have a 2005 Jaguar XJ8L with about 52,000 miles on it. Great car. Love it.

I have a new iPhone 4. Great device. Love it.

The combo of the two… Not so good.

When talking on the phone in the car NOT in speaker mode and NOT using a headset (I hate using either), I hear an annoying clicking from the phone and it sounds to people on the other end like I’m “talking into a fan.” Another person described it as “being attacked by a swarm of angry moths.”

In any other car the voice quality is fine. In MY car with the engine OFF the voice quality is fine. In my car with the vehicle on and all the electronics running, but the engine OFF, it’s fine.

The minute I start the engine, the call quality goes down the tube.

If I switch to speaker or headset the quality is fine again. The problem only happens in that car on that phone using the normal handset mode.

This problem didn’t happen with my iPhone 3G or any other cell phone that I can think of.

I’ve already resigned myself to just using the headset, but I still want to figure out the root cause of the interference.

Apple already replaced the phone for me and it made no difference.

My next step is to go to the Jaguar dealer and ask them to replace the car. No, not really. However, I AM going to go start one on the lot that is the same model and similar year to see if it’s just an iPhone vs. XJ8 thing, or if it’s just MY car.

Weird huh? Any thoughts?

GOOD! Hang up and DRIVE!

I wish all phones did that. Then I wouldn’t have been rear-ended in plain daylight while sitting at a stop sign by a girl on her cellphone.

At least you got her number.

Most likely, one or more of your COPs (Coil-On-Plug) is marginal. When they start to fail, they generate a lot of electrical noise. They can do this for a while before any misfires are detected.

Thanks for the productive answer. My concern is less about the phone and more about what the heck is my engine doing to create that type of interference. Thanks.

If you have been paying attention to the news, you’d note that the iPhone 4 is plagued with reception problems. This has been confirmed by Consumer Reports who does NOT recommend the phone because of this issue. I’d wait for Apple to come up with the fix and likely recall of the phones before losing any sleep over it at this point.

It’s not a reception problem. I can use the speaker on the phone and it’s fine. I can plug a headset into the phone and it’s fine. The only time it happens is if I’m NOT using either of those audio mechanisms. Also, holding the phone or not makes no difference and case or no case makes no difference.

It wasn’t her fault, it was yours. For being stopped in front of her, at a stop sign, while she was on her cell phone(because she’s important D: )

Turn off the phone and drive. If you need the phone park and talk.

I would agree with the coil concept, as my radar detector is basically useless when I have a coil going bad, but that would not explain why your phone works in speaker mode or with a headset. I still think it has to do with the current iPhone bug which occurs when holding the phone a cetain way, which you would be unlikely to do with a headphone or speaker.

OMG!!! I cannot believe that someone else is reporting the same problem that I have experienced. I have a 2005 XJR and while driving it I experience a fast tapping noise on the phone. I know, I get it… Someone tapping and telling me to get off the phone. I even experienced the problem after exchanging my iPhone4; however, my partner’s iPhone3G doesn’t experience the problem. I tried to explain to Apple that I felt the iPhone4 was more susceptible to interference but they wouldn’t buy it considering how many millions of phones they have sold and all of them mostly being used while in the car. They say they have never heard of the problem. I guess they haven’t driven in a Jaguar. Well, at least I am not the only one having the problem now. If I turn off the ignition the problem goes away.

In the old days you could tell if your spark plugs needed attention if the engine started interfering with the radio. At 52k miles they shouldn’t be worn that bad but worth pulling them and checking condition and gap. Coil(s) would be next suspect if coil on plug arrangement, otherwise wires.

There was a notice sent out a month ago saying that the owners of their cars that have recently purchased the iPhone 4, need to place it in the trunk of their car to improve reception quality, while driving.

The engine interference will affect all iPhone 4’s in the cabin of the car due to the electrical patterns created by the engine in operation.

They aren’t saying that its a problem with the car, because every other phone works fine in the car, and the iPhone 4 is obviously the problem, not their car, since their car was built several years before the iPhone 4 was released on the market.


oh man that’s too hilarious. Looks like they rushed the 4 out too soon, yet people are still going nuts trying to get one

Ugh… SO frustrated!!! After 20+ hours of Apple support both online and in store, THREE new phones (yes 3), wiping out my software, replacing the sim card, I finally stumble across this post. Wish I or one of the many geniuses had thought to research online first. Least now I know what it is… Question is when/how are they going to resolve it?!

Steve Jobs will say ‘Your holding it wrong. Don’t hold it that way.’

I’m guessing that there might be two “problems” that just happen to have fallen into alignment. First, the antenna in your iPhone really is not what any RF engineer would prefer. They’d probably like to have something bigger. (and clear of your head). (and not inside a steel cage) So your signal is likely marginal to begin with. Second, your Jag appears to be emitting energy in the same band that you are trying to communicate on and the energy is somehow feeding into the phone through the antenna and getting into the RF amplifier. Presumably hooking up a handset or the speaker alters the reception pattern enough so the phone still functions.

Why not try rolling down the windows then starting your Jaguar and letting it idle? Walk away about 50 feet and call an helper who will report voice quality. Walk toward the car asking “Can you hear me now?” and try to map out the area where the phone misfunctions. Poke your head and phone in through the windows. I’m guessing that the phone might work perfectly well every place except some places in the cabin.


I have to agree with Caddyman. It would be a better world if cell phones did not work in any non-emergency vehicle that is powered and moving. There are too many folks out there who are incapable of multitasking. Trying to stay out of their way when they try to do anything – whether driving or buying groceries – while talking on a cell phone is becoming increasingly annoying. What we need is a social compact. Cell phones are fine, but only when you are in a fixed location and are out of everyone’s way.

Thank goodness I added “Jaguar” to my googles. I spent all day yesterday, talking to so called Apple and AT&T experts. No one had ever heard of this problem. Mine in a 2004 XK8. Exactly the same problem. Has anyone tried to replace coils? Does anyone know whether this will work?

I have seen claims in some Jaguar forums that it is the proximity sensors inside the car that are causing the problem. I haven’t found any confirmation of if it’s the coils like I thought or if it’s the sensors. Apparently, the new Jags don’t have this problem.