I ready WhiteSTR's post and was just wondering what area would you use the cleaner-around the sensor/throttle? Appreciate the advice, very new to Jags.

Happy New Year!

 

Before you go under the hood, invest $3 and put some dry gas in your tank and top off your tank at a gas station that you do not normally use. You may save yourself a lot of hassle.

 

Hey Cincinnati well i took it to my local Jag repair shop, good guys, tell you whats wrong and explain what it does, so mine is the sensor but being the Jaguar way you just cant get the sensor that tells the car how much to rev up or gas to give,sorry forgot exactly but you just cant buy the sensor alone,you have to get the whole throttle body so its $879. plus labor. So my car will go in for that and while its in there im going to change the front brakes which will be another $695. the saying is true isnt it: You dont have to be rich to buy a Jaguar, but you have to be rich to keep it running.

All the best!

 

hey Jeffg. thanks for the info, quick ? though what exactly do you mean "dry gas"?

 

YES IT CAN!! I put the Mina cold air intake on my 04 XJ8 and after spending $$ at the dealer, they discovered it was the cold air retrofit causing the problem. Luckily I had saved all the original parts and converted it back to stock and no problems since. These cars are very sensitive to changes and can give all kinds of problems when doing so. I do have the Mina exhaust with no problems. Seems to be more issues with intake as opposed to exhaust.

 

Hi,
"Dry Gas" was a common term (and product) used in every car in the good old days to inhibit condensation that collected int he underground tanks at gas stations.

Today it is harder to find, but if you read the labels of most "gas treatments" and look for one that states that it contains a "moisture inhibitor" you can use it. At Walgreen's Drug Store I found a Gas Treatment by Gumout that cost $1.99 that worked fine. I now use it every 3000 miles. Better than a $800 throttle body.

Best of luck,
Jeff

 

Ok all, I am having this issue too...the engine just sputters alittle and the idle is around 1500 in park and 1000 in drive. The DSC and Engine Systems Fault error comes up. This started a week ago and I put name brand fuel in (92 grade) and I noticed if I let the car sit over night it would run fine for about 3 minutes then it would go back into the Engine Systems Fault error. The other day I put some "dry gas" in and let the car run at idle for about 4 hours and when I went back to it the car was still at high idle. I turned the car off and immediately turned it back on and it ran just fine. As a matter of face I took it on ride all day about 100 miles with turning it off and on as I stopped places. The next day went to turn it back on and it was immediately back into Engine Systems Fault again. What are my options here?

Thanks,
Stan

 

hey Jeffg thank for the advice,i actually went to kragen and picked up something that has the moisture inhibitor. luckily though since i took it to the shop and they cleaned the codes and fiddled around with it it hasn't happened again,its been about 400miles since but its a bit nerve racking knowing that it may happen but got my fingers crossed. Aappreciate the knowledge.

 

You really need to put your car details in your signature.

Staying in high idle tends to mean something either kept it out of closed loop (e.g. bad O2 sensor) or an air leak. Which is more likely depends on your car details.

 

Forget the air flow sensor. If you disconnect the plug of the Throttle Position Sensor and then turn the key to "ON", but DON'T START IT, You will see those same warnings. In a lot of cases the problem is with the wiring and The Jag JTIS CD will call for a wiring check first. Try this. On the side of the throttle body, you will see a plug with 4 wires and it is towards the drive's side of the the throttle body. This is it and try unplugging it, look for corrosion. Plugging and unplugging it several times can fix the connection problen if the corrosion isn't too serious. CHECK THE WIRING FIRST. Squeeze the plugs lock inward to unlock it.

 

Jeffg, I took a variation on this theme and got a bottle of Gumout Complete Fuel System Treatment. It removes moisture/water in addition to treating valves and injectors. My mechanic worked on the MAF, checked and cleaned contacts on the throttle body (replacement was next) and did everything else to diagnose and solve the "Engine Systems Fault, DSC not available, Park Brake Fault" issue.

My 2004 XJ8 was in the shop for two whole days ... we know that's never good. This was after it went into limp mode 6 to 8 times within just a few days (twice on the freeway!). Everything ran fine when I picked up my car this past Friday evening. I racked up a few miles that evening and to my utter dismay, it happened again! It took me about an hour taking the streets home. What made this all the more disappointing is that this Jag certified, former dealer mechanic has been working on my cars for the last 17 years. I owned an '89 XJ6 and a '99 XJ8. Of course they had their issues, but nothing like this. So why was this problem still lingering?

Jeffg, that's when I read and re-read your post. So about midnight I took the trip down to Wal-Mart's automotive ...put in a bottle of Gumout and then topped off at the local 76. BTW, it happened once more on the way to the service station. Well after putting in some pretty extensive driving over the weekend, I'm starting to feel confident about my ride again. Thanks so much for sharing your experience!

 

The Gumout worked for a little while, then everything came back with a vengeance. Whereas before, when the problem was intermittent, it got so bad that things went into full on "limp mode". I had to drive for miles down a busy thoroughfare all the way home.

It's been problem free for a couple of weeks now; but it took replacement of the Throttle Assembly ($250) and Throttle Body ($850) and $400 in labor to get everything squared away. It was a real pain in the you-know-what. After owning 3 Jags, it was enough to make me start looking around for another brand. I got over that. Good luck to anyone else who encounters this problem.

 

That should say, Throttle Pedal Assembly ($250). Thx

 

I know this thread is old, but wanted to say thanks to everyone for the good info in it. Replaced the broken Coolant Reservoir, cleaned the Throttle Body and MAF with CRC products, replaced Air Filter, epoxied corner of Air Filter Housing I broke, will add the $1.99 Gumout when the fuel tank is lower, and am sticking to Premium fuel from now on. So far so good with the "Engine System Fault/DSC Not Available/Parkbrake Fault"

 

The problem for me was the grade of gas. The computer was sensing a timing problem and sending a signal to the computer that there was an engine fault. As soon as I put the new highest grade gas in and it reached the fuel injectors, I have not had the problem now for some years.
The other signals sent to the computer are triggered by this also.
I would not let the dealer spend all this money, when he simply assumes that you are doing what the instructions require and he goes from there.

 

Can anyone tell me where the MAF is or a picture as this happened to me today and an going to clen it first.

 

If you got the warning that this thread is based on, forget the MAF, that is not the problem. However it is between the air cleaner and the throttle body and it has the wires connected to it. Be careful as it is easy to break the air cleaner lid.

You real problem is that moisture got into the throttle body plug. It is the four wire connector on the side of the throttle body. Push in on the lock and disconnect it. Use something like WD-40 and spray the 4 pins that you see and spray the inside of the plug. Connect and disconnect this plug about 4 times and you are good to go. I find that I have to do this chore as routine maintenance now. A dealer will want to change the throttle body and that costs big time. It can be done yourself and this web site lists rebuilders.

 

The throttle body has two position sensors in it, they have to check each other .. if the signals is out of spec, you get the code. Since these sensors have moving parts, they wear out. The sensors are not available as spare parts, but rebuilders can get them. If you send the throttle body to one of them, they can make it like new for about $500. It is also very easy to change this part, so for $500 you can solve it. Cleaning the MAF is not going to fix the problem. As was said, the other issue is bad connections at the throttle body. The sensors operate at low voltages and current, meaning any tiny resistance in the connection will lead to a fault. Clean them up first if the problem pops up.

 

I'm having the exact same problem. For me, both TB sensors were bad. Had to buy a brand new TB. Fortunately I bought one on eBay for under $500 and took to an independent shop. From what I understand, it's really a crap shoot. I would try everything everyone has suggested. The only realy way to know unfortunately is to get it to throw a code and get the code read at a mechanic shop...

 

Can a non mechanic do this like me? and if so can you give me specific instructions on how to perform this and location?? Thank you I just don't want to spend all my money on a Tb now that it's xmas time....and I'm broke...