hello everyone, so i finally experienced what i hope isnt a major problem on my recently acquired 2003 S-type R. Last night just cruising around town, my car was driving just fine. I make a quick stop at CVS and when i turned off the car it suddenly starts beeping. now this was the first time this has ever happened to me so i was a little worried. i quickly turn her back on. and everything seems fine and dandy, i turn her off again, no beeping. so i keep it moving.. i get back to the car, turn the key, BEEEP BEEP BEEEP BEEEP BEEP! at this point all i wanna do is get back home. i Start her up. she feeels perfect.. right before coming to a stop at a red light, i feel the slightest of a jerk.. "Transmission Fualt" light goes on, i panic, pull over and when putting her a Park, a real hard Jerk.!!! put her back on Drive, it jumps again.. switch her to Reverse, even worse!! at this point, im as sad as can be. eventually made it home. went to sleeping praying for the best.

This morning i took her out for a run. The "Transmission Fualt" message is still displaying. MY check Engine light is on. The cars jerks real hard when swtiching over from Park to Reverse to Drive (worst jerk being the R) and when driving at Highway speeds the vehicle goes into Restricted Performance and wont allow me to go over 55mph. Starts slugging and lowers RPMs at anything over 55mph.. what has happened to my Jag??

as always, any help greatly appreciated.

 

Could it possibly have a failing battery? It sounds the most likely cause.

 

jagv8 - the battery? really?? i did make a thread about a month ago about not being able to access my trunk to due the battery draining and therefore the trunk release not working.. however, since then my car has never hesitated on starting...

i really hope your right though, i much rather have to replace a battery than anything transmission related.. any reccomendations on a good battery?? autozone is less than 10 minutes away.. thanks again for your help.!!

 

Do you have a multimeter?

Can you test battery voltage with the car off and the car running?

It may be a low voltage condition, or something else. If the battery voltages are good with both conditions, it's time to get the car on a scan tool and see what the codes it's thrown are.

Take care,

George

 

You'll struggle to detect a battery that's on its way out on any modern car. You need to check the lowest the voltage goes for (say) 1 millisecond during cranking and starting. Preferably, the lowest it drops at each module. You need that minimum voltage to be enough that each module is happy. I think that's about 9.8V but it will depend on each module. (This way lies madness.)

George - do you have another way?

The codes will be garbage if it IS a failing battery. We've seen that a LOT on here over the years. (Also on the .co.uk forum.)

The car will commonly start yet throw weird electrical etc issues with a bad battery. Again, we've seen it SO often.

Do some searches on battery and you'll see.

 

Well, with the car off he should be in the 11.9 - 12.4 v range.

With the alternator running, he should be in the 13.4-13.8v range.
(unless he's high cause the voltage regulator in the alternator is dead)

If any of those readings are off, battery for sure.

Voltage drop on start isn't much of an indicator. He could pull the battery out, and have it tested at any of the parts stores through their charge / discharge cycle tester.

These are just the basics.

Take care,

George

 

BINGO.....my unprofessional thoughts are a vacuum leak causing the tranny fault

 

How many miles are on the car?

 

i believe its my battery guys.. tried to turn her on and shes completely drained. Picking a new battery up first thing in the morning.. any suggestions??

 

I'm a firm believer in optima batteries.

I put Optimas in everything generally I prefer the yellow top because it can take more of a beating, but then again my car has an "upgraded" stereo.

it's not a 100% direct fit, you need to make your own tie down, I used perforated exhaust hanger.



Take care,

George

 

I referred to and meant Voltage While Cranking. That's what causes rogue lights and codes so often. And it's hard to check how low it falls during cranking. If you can't be sure and the battery isn't newish, just replace it. As an alternative, read any codes and if there's no pattern to them replace the battery.

Or.... keep seeing what happens and sooner or later you'll be left with a mess, such as a car that dies on the highway and strands you.

 

ok so today after work, i went to autozone to get a new battery. i wanted to be 100% sure that my battery was no longer good before dishing out $160 on a new one, so i stopped by my car to get my battery and have them test it.. they hooked it up to the machine.. turned some knobs, pushed some buttons, "GOOD BATTERY".. such a "GOOD BATTERY" that the autozone clerk recommended i DONT buy a new one.. he said all it needed was some charging.. he took my battery and told me to come back in 10 -15minutes to pick it up.

10-15 minutes later.. .. . i get my battery back, thank the guy, and head to my car.. put the battery in place, lightly clean both terminals, and tighten them in place.. I start her up... NO "transmission fault" message. NO jerking. No more "restricted performance" message... like it never even happened.. any thoughts.??

check engine light is still on.. but that was on before this incident. car has 98,XXX miles btw..

 

While you were at The Zone, should of had them read the codes for the check engine light.

 

Well if indeed the battery is OK then it has to be draining somehow or else the charging system is at fault. I agree with getting it scanned. My bet is whatever did the battery in will happen again.

Low voltage does do some weird things on newer cars. I had a Grand Prix I fixed that I had put a used battery in out of a parts car. I had it parked outside and went to pull it inside. Engine began missing and backfiring then the engine light came on. I hooked the scan tool on and it gave me a code for evap emission fault and random misfire. Pulled my hair out for several days swaping ignition coils, mag pickup even the fuse box since it had been damaged. All the while I had been hooking the charger on the battery since it kept going down. Decided to just go buy a new one. Started it up, held the idle up for several seconds and it smoothed right out and the engine light disappeared.

 

George, that's not a cable sandwiched between your Optima and the strap-hanger is it? Surely the pic deceives me!
-Zane

 

Not sandwiched.

Follow the strap hanger to the right, see the dark wedge? That's the tenson point of the hanger, that and the corner of the battery. There's at least 3/4" of clearance between the cable and the hanger. But yes, the cable goes under the hanger. (zipping up flame suit now).

Take care,

George

 

It's kewl
I was prepared to compliment u for the apparent slack in your battery strap, given u routed a cable under it......but it all makes sensewith the wedge. Didn't see that.

 

im back with an update fellas.. on my way home from work.. my car was driving just fine.. i get to a red light.. then BOOM.!! the car start rumbling from the back end.. "Engine Systems Fault"... "Parkbrake Fault".. "DSC not available" both the yellow and red warning lights were on.. and my car wouldnt go past 1500rpms.. about 6mph..!! i hit the emergency lights and pulled to the side of the road.. i turned her off and waited for about a minute.. once i started her again.. all lights/warnings were off.. i get back on the road.. 4-5minutes later... the exact same thing happens.. luckily, this time i was literaly right infront of autozone.. i pull over and head to autozone to buy a Code reader..

i connect the Actron OBD II pocketscan.. and it pulled up 9 codes!! they were..
- P0300
- P0303
- P0308
- P1313
- P1314
- P1316
- P0121
- P1058
- P1111

What am i dealing with here fellas..??

i was planning on getting my 100k service done on Saturday.. shes currently at 98,500 miles.. as well as getting a new Optima battery with complete disregard of what i was told at Autozone about my battery being "good" however im just really frustrated at this point..

as always, any help greatly appreciated.. thanks.

 

The P0300, P0303, P0308 are cylinder misfires sounds like you had a misfire on #3 & #8 cylinders could be a coil pack or a spark plug. You also have a P0121 TPS code that could be a bad connection on the plug. The P1314 & 1315 go back to the cylinder misfire. The P1058 I think should be P0158 it the H02 sensor circuit high voltage. The P1111 is a system check. I am attaching a OBD code chart http://www.gusglikas.com/images/Auto...tos/P20003.PDF

As for what to do I understand old or low voltage batteries could cause funny things to take place so checking it first would be a good idea. The cylinder misfire seems strange for both to fail at one time but is a possibility. TB or TB plug could cause the car to stumble and go into failsafe mode and that would restrict the performance of the engine. The H02 I think is a result of the TB & cylinder misfire. I would check the battery and the TB plugs first, clear the codes and see what takes place.

 

You never finished the job with the battery.

When a parts place fast charges your battery, it only gets a surface charge. That's enough to get your car started. But, there is very little reserve capacity.

Your next steps should have been:

1. slow charge your battery at a low rate
2. determine why the battery was not being maintained by the charging system
3. fix what is found in #2

Your charging system should be able to maintain your battery in a good state of charge. If it cannot, then the problems just keep on repeating themselves.