Hello,

My 1999 xj8 is my weekend driver and gets out every now and then. Last weekend i changed the battery (car sat dead for a few weeks) and drove about 60 miles no problem. The car sat a week and the temperature has been dropping.

I started it yesterday and it started right into restricted performance mode and once i put it in drive and pulled out a little the check engine started flashing. The car idles rough and i moved it a little around in my driveway and got it to idle normal right before shutting it down (still was RP and CE flashing). Although the RPMs drop low when i take my foot off the gas on idle and come back up to ~700.

On my OBD reader I am getting: P304, P1313, P0351, P354, P0356, P1000. I did a quick look under the hood and all the air hoses look good.

I changed my coil packs and plugs about 1.5 years ago. Any help and suggestions is appreciated.

 

Flashing check engine light = active misfiring coils causing potential damage. Focus on cylinder 4 mainly but also Cylinder 1 and 6 - check coil connectors.

 

DO NOT operate the vehicle under conditions that cause the MIL to flash as catalyst damage is occurring.

Find and correct the misfires or you'll be facing DTCs P0420 and P0430.

 

Also try posting in the forum for your car, which is an X308 series. This forum is for the car that followed yours, the X350 and is totally different in virtually all respects,

 

thanks all i will check out - i reposted in the correct 308 section.

 

If there is an actual problem -- you will get the code on startup. If sensors pick up misfires you will get the flashing CEL .... this is an additional warning.

My advise in the other thread was for clearing .. for lack of better terms. When the car gets confused with low voltage/ battery chage .... both of my 02 have had this happen.

When you have an actual problem -- hard code that comes up on start. This will have to be addressed. Clear the codes ,,maybe more than once. Start the car and if the CEL is on ... turn the car off and check the codes. What happens after you run the engine for any length of time --- other codes will come up. You want the first one.

When the car gets confused .. the RP is on at start. It does not come on seconds after start-up ... that is what it should do if it has an issue.

Sound like you may have to check some things out ..... was there any moisture aroudn the coils when you pulled them

 

Thanks - I will try reclearing a few more times. I switched around the coils, cleared the codes prior to turning the car on (read no codes), made sure the battery was fully charged up, and still getting same sluggish start up, jumps right into RP. I did notice the car was reading RP even before starting it up. The coil packs were dry.

I am going to use my multi meter to make sure the correct volts are traveling to the coil packs.

I just remembered my last oil change they had put a tad too much oil in and sucked it out. My cold dipstick currently reads full so I am not sure if that could have played a roll

 

I can't say I remember the cars ever giving me a bad coil code or coil circuit code. But -- don't really look .. know what it is on startup and just clear them out.

The cars do have the Throttle Body sensor issue -- they get dirty. That's why I said to push the pedal 50 times. I have had the RP come up -- typically on moderate power pulling from a light. The car will lose power and shake ----- Sometimes just restarting it will reset everything. But if you are in a location where you have to drive the car a bit to get into a safe spot the codes will increase and normally one of the misfire codes is now hard and the CEL will be on. I know that my issue as there will be a TB sensor related code.

You have to keep clearing the codes so no RP comes up before restart ... sometimes that's it ..... other times it takes another attempt.

It sounds like you may have an actual problem if the coil code is hard and first --- you may have to pull the plug. Make sure nothing wet. It will most likely be a waste of time -- but you need to do the simple things. Follow the service direction. Check all the wires and connector at that coil.

Both of my cars are basically untouched ..... One I bought new and it has had very little done to it in 70k .. the other is a garage queen with 30k -- even less done to it. What I'm getting at is ..... I know other than an animal or something .... nothing has been moved around or damaged fixing or replacing parts. When you work on old cars it's not uncommon for something else to get damaged .. the parts are old.

 

Codes are still sticking to 1,4, and 6. pulled and swapped the boots and still staying. Cleared the codes and tried turning the car on a few times and it runs for 1-2 seconds and jumps into RP.

I did have some mice in my garage the last few months, but don’t see any issues with wires under the hood. I have not tried to check power at the harness at the plug connections, how would i do this with my multi meter?

 

Check the wiring looms for damage and see if the plugs at the injectors are correctly seated.

A pin test, which is outlined in the Workshop Manual, can be accomplished to check the performance of the wiring and connections.

I know you replaced the battery, but what is the voltage across the terminals with the ignition in the OFF position when checked with a voltmeter?