Hi I live in Virginia and I bought an XJ8 (x350) that has a hard time starting and then runs rough until it reaches normal operating temperature. I've replaced the MAF, the coils, the spark plugs, the thermostat, and the 4 fuel injectors on the passenger side. Wondering if Crank sensor or cam shaft sensors need to be replaced. Once the car is warmed up, it runs fine. Thoughts?

 

Welcome to the forums Speed 2004,

Throwing parts at a Jaguar soon gets expensive and you have built up quite a list. My first thoughts from your description would be a suspect temperature sensor. However, having the codes read to see if there's anything relevant stored or pending is the first logical step in troubleshooting powertrain issues as it can help target possible causes and eliminate others.

Follow this link https://www.jaguarforums.com/forum/x...-x350-x358-28/ to the X350 forum for help, advice and information. The 'HOW TO' thread at the top is a good place to start for information on regular issues. You can also use the US Mid Atlantic Region forum by following this link https://www.jaguarforums.com/forum/us-mid-atlantic-65/ to find other members in your region.

Please read the guidance for new members ( https://www.jaguarforums.com/forum/n...ned-up-241802/ ) which answers many of the most frequent questions about getting started.

Enjoy the forums.

Graham

 

Welcome aboard…

 

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Hello,
I hope you soon Zero in on what the problem really is and get it Fixed. It's not fun throwing money at a car that refuses to respond to your attentions.

Welcome to the forums form ElinorB.
(';')

 

Welcome to the Forums.

 

Welcome to the forums.

 

Welcome to the forum Speed 2004,

Good to have you with us.
Enjoy the forum.

If you haven't done so already you should add your car details to your signature to help others to help you.

 

Which temperature sensor? The coolant one? The air intake temp sensor is built into the MAF.
I don't mind replacing parts since the old parts are pretty old and probably need replacing. The car has 189,000 miles.

 

The coolant temp sensor?

 

welcome to the forum

 

Were these in response to my post? If so, a QUOTE helps makes things clear.

Jaguars have 'low volume, high flow' cooling systems for rapid warm up which is designed to reduce emissions and comply with requirements in the various World markets.

You should notice elevated RPM on cold start which soon drops to normal as the coolant warms up. This is controlled by signals from the coolant temperature sensor to the ECM. If the sensor is faulty, starting can be difficult and some relevant codes can be set.

Graham

 

Thank you for your insight, Graham.
According to my OBD II scanner the ECT this morning when the car was cold read 55 degrees F. The temperature this morning in Virginia was was 32 degrees F. The car started but ran rough sitting at idle. It didn't warm to normal operating temperature for 18 minutes. Replacing the Coolant temp sensor would be a cheap fix.
The car was outside all night, not in a heated garage or anything. Does that 23 degree difference between the ECT and the ambient temperature seem suspicious to you?
Thanks

 

See my post from 3:42 pm.
Thanks

 

That IS odd. I'd expect to see true temperature readings to be reported from ambient at startup through to normal when warmed up. An incorrect initial temp will inevitably cause incorrect fuel trims and is likely to account for the rough running. Even so, 18 minutes is a very long time to warm up and there could be a thermostat issue too.

We were 34 deg F last night in the north east of England. It's getting colder but haven't seen freezing point yet this year.

Graham

 

From one Virginian to another: WELCOME!!!

Dwayne