I come to this forum following a phone call yesterday from my mechanic saying that they have tried two "used" TB's neither successfully and I might have to re-consider a "new" part from Jaguar. (Cough..cough)

MY QUESTION: Is rebuild the way to go and is ASI/ATE "forum approved"?

History: As best I recall, about 4 months ago I replaced a knock sensor due to a "gearbox fault". Probably unrelated. Shortly thereafter, I would get random occurances of "safe mode" (on some occassions the "gearbox fault" reappeared as well) which upon turning the car off and waiting briefly, would reset and the car would drive fine. I actually became rather complacent when the fault(s) would occur, feeling confident a short wait and restart would put me back on my way. Then about a week ago, it wouldn't reset. I limped it to the shop. I was told that codes indicated I needed to replace the Throttle Body. The shops normal sources didn't have any used or rebuilt TB's and new would be about $2200 from the dealer. I explained I wasn't going to do that. Later in the day, I was told they'd found a used one with a 6 month warranty - $1,000 - I said ok. On Friday at 4 pm I was told they've tried two used from same supplier and neither would work. I said I'd get back to them on Monday.

I have read a number of the threads/posts on this topic and it appears to be a pretty common problem. I have seen the reference to ASI/ATE rebuilds for $489, but I really can't tell if this is just crafty marketing? There are LOTS of sellers on Ebay with a wide variety of prices?

ASIDE: Additionally, now I've read that there is a TSB which includes my car related to TPS/wiring harness gold/tin issue. I guess I'll check to see if they found the P0121 code as well?
FWIW, I have printed several of the threads for discussion with my mechanic on Monday.
Thanks in advance for any thoughts, insight, comments. Cheers, Jeff

 

I had p0121 code...... Sent in my TB To ASI a few months ago. So far it's working great. Also it was a quick turnaround time. Lifetime warranty also....Good Luck

 

With all the plugging and unplugging done with swapping out three different throttle bodies I suspect that the poor connections issue was overcome, at least temporary. TSB 303-58 does, indeed, apply to your car. You should be able to find that with a search on this forum. Ask your tech for the specific codes read. Perhaps they will offer alternative solutions before you have your TB rebuilt.

. . . and welcome to the forum!

 

welcome to the forum and sorry to hear your cat is ailing!! Hope all works out.

 

Unusual to get two u/s rebuilt TB units from a reputable source.

Can we safely assume you are using a Jaguar specialist who knows about battery disconnection as part of the TB change procedure?

Graham

 

It is improbable that you exprienced two bad units, the problem lies elsewhere.

My throttle body was acting up, I thought, and I sent it to ASI/ATE. They are good - I had it rebuilt a couple of years ago, no problems since. There are wear items in the throttle body so they do give out over time. Don't buy used or new. Rebuild the one that came with your vehicle and replace all the hoses connected to it and the Fuel Pressure Regulator hose while you are at it.

However, here's what my problem really was - the large connector lost it's locking "tang" and although it felt as if it was seating correctly, it would slowly work loose at random times. As it did I would get all sorts of TB related fault codes.

Once I realized that was the issue, I simply made a set screw arrangement through the outer plastic shell of the connector to lock it to the trottle body and my problems stopped entirely and immediately.


The TSB regarding mismatched metals on the TB elctrical connction is theortically correct but hard to implement, I could not find the kit easily and it was very expensive when I finally did. With all the splicing needed to implement the fix, I just passed on the idea.

 

The battery question crossed my mind as well when I read an earlier thread of another owner's DIY repair and that the battery disconnect solved his situation.
This shop repairs other Jag's 'cause I've seen them there personally. I was referred to this shop by a good friend who works with CarMax and said they send their import cars to this shop with very good success. I've used the same shop for about two years now, so that's like 5 repairs.

When the coolant sensor failed and we first tried just to replace the sensor and it didn't work, Keith said we needed to replace the reservoir and sensor together. I thought this was crazy, but it worked, and of course cost three times as much. Apparently those sensors are we'll....quite sensitive. LOL Point is he apparently has "some working knowledge" of Jag specific issues. But as to the question, that certainly seems a possible explaination.

Now that I think about it, the window return started failing just before the 'resets' stopped occuring with restart. I know that's a sign of weakening battery. I don't know what part a weak battery would play in all of this???
Thanks for the posts. Jeff

 

@ Spurlee.....sounds like good information. With two good recommendations, I see myself going ahead with the rebuild to eliminate that question and working forward from there. That option is actually cheaper than the used part that was quoted to me. : )

 

That's often the case. I'm a big fan of rebuilding the unit that came with the vehicle rather than trying to match part numbers with eBay stuff. If you have the $400 and are going to keep the car you'll be happy with the decision.

 

It was probably the float, which is a captured part of the reservior, becoming saturated. I went through this a few months ago and devised a work around. There is a long thread dealing with the saga.

Good luck!

 

Can you ask them to tell you the codes they pulled from your car giving them the indication that it was the TB? As for the codes P0121 is a typical plug connection compatibility issue, a P1121 code is a throttle position sensor and that justifies the TB replacement/rebuild. As a side note ASI did my TB and it is working just fine with a lifetime warranty. You mention window memory being lost and that is typical of a failing or weak battery I would recommend that you get a load test done on the battery first. A low battery as mentioned will give you false readings and codes.

 

Feeling rather dumb for just dismissing the window memory as unrelated. I should be well educated by now that everything is potentially relevant!

Coming to the forum and sharing/learning....a step in the right direction for sure. Update to be provided Monday afternoon.

Cheers, Jeff

 

I spoke with Josh this morning. Initial fault code was P1121 (PPS). Not aware of the rebuild possibility, used was attempted. The used TB's gave TPS and TM codes and Josh said he spent 5-6 hrs moving the TPS from my TB to the used and other adjustments without success. He is in agreement that rebuild is best alternative and I'm to pick up TB and ship it to ASI with expectation that this will resolve this issue.

As for my battery, Josh had already addressed charge/load test which it failed. So it appears I need to replace the battery. I asked if he recommended Interstate. He said, "If we get a good one, it'll be great and last 4-5 years, but I've had poor experience with getting weak batteries possibly due to them being expensive and having been shelved for some time". I said how much more expensive with response of about $50.00. Now I'm perplexed. My recollection is that Interstate was/is highly regarded.

Anyone else familiar with this issue? I guess I'll have to search the forum now for battery recommendations while I wait for the TB rebuild. In any case, A BIG THANKS to everyone who took the time and commented/assisted with directing me in this problem.

Cheers, Jeff

 

I don't know where he is getting the Interstate, but they don't seem very expensive to me. A lot of members here have them.

 

A number of us have had good success with the vented Bosch battery available from Pep Boys. With the appropriate $20 coupon (usually found on their web site), you can typically exchange your old battery for a new Bosch for right at $100. I replaced our XK8's factory battery with a Bosch one back in late September and have had zero problems with it. One caveat - check all six cells for proper water level. I had to add a bit of water to all six cells to bring them up to where they should be. Going forward, I check the cells' water level at least every couple of months, and more often than that during our hot summers....

 

Or go to Sears. All you want is a good battery not one that is going to put you in the poor house. I got my battery from a local battery shop, it is the amperage load you need to be concerned with.

 

I just sent my TB to ASI for rebuild. FWIW, it fits perfectly in an 8 1/2 x 11 USPS Flat Rate Priority Mailing box. Added a small amount of foam packing curls and ready to go. At this point doesn't take very much to make my day and me happy.

 

I want to share that the rebuild process on my 2001 XK8 throttle body appears initially successful.
Josh with D K Hardee called this morning and said he'd installed the rebuilt TB and a new battery and completed a test drive. "She's running like new!" are GREAT words to hear from your mechanic.
Thanks to the forum I learned that rebuild is a viable option. I also learned that ASI does the rebuild for significantly less than the expense of a new part. Thanks go to ASI (Automotive Scientific, Inc.) for a reasonably priced rebuild with a return of about 7 days.
FWIW, I recall that under warranty (near 40,000 miles) I had the TB replaced. I'm now at 91K, so I guess 40k-50k is a TB lifespan.
Cheers, Jeff

 

I have a 2000 Jaguar XK8 and like many of you the throttle body has gone bad. I have 107, 000 miles on it and I am on my third TPS. I've noticed you've mention ASI. Please give me more information. I will try rebuilding instead of buy a new one--I've tried new from the Jaguar dealership and it only lasted 13 month, one month past the warranty. I then purchase a used one from Jaytran Industries with a 2 year warranty and almost every month I was sending it back until I just parked the vehicle. I like my car but $2500 for a TPS which last only 13 month is a bit much.
Please help.

 

COMPUTER ISSUE??? I had similar issue with my 97, TB error codes, ABS errors, no guts when you got on it. Tried 3 diff TB's, no help. Turned out to be the main ECM, as it is an issue with early year Xk's. Send it out to autoecu worse case is that you spend a diagnosis fee if that is not it.