My 97 xk8 convertible recently started running rough, difficult to accelerate, poor idle, and then would frequently stop from idle. Dealership diagnosed bad ecm unit. The ecm # is LJA1410AK a Denso product and the car vin is 007676. Found some repair/remanufacture companies via internet. Does anyone have any experience or opinoins on whether these repairs are worth the cost -- $575 to $625 with warranties of 1 year to lifetime. Dealer couldn't find part and wouldn't refer to repair company, so jag was towed back home. I removed the ecm. Is it plug and play if I do get it repaired? Comments appreciated.

 

Since you have the part #, search on eBay. Some ECMs are direct swap, plug and play. ECMs are about $100 or so online for secondhand. You may need an immobilization reset, but that would be no more than 1 hour of labor at the dealer. Worth a try. If it does not fix your problem, just resell the part.

 

I bought a TCM for my '97 on ebay recently, and so far it's working. That's not as big a deal as a ECM, but I think if all the numbers match it might be worth taking a chance. Either way you go please report the results here so others can benefit.

 

Thanks for the input. It may be awhile as the car is kept in Florida and I'm not there as much as I would like. What I've been told by some of the rebuilders is that they don't alter the programming so should be plug and play. but they won't honor the warranty if you install and short it out. Dealer wants $337.50 to install and reprogram. If I could find a $100 -$200 unit on ebay, I'd take the risk and install it myself -- though it might still not run. I'll post as soon as I've taken the next step.

 

Just disconnect the battery when you install it.

 

I had the ECM in '97 rebuilt, and it has been flawless ever since, which was about 2500 miles ago. There are no worries with disconnecting or connecting as long as you disconnect the battery first, as WhiteXKR mentioned. Also, there was nothing to have reprogrammed (just the usual window and radio station re-set due to the battery disconnect).

John

 

This might help -

The first 3 letters and following digits of the part number must match exactly. However, the letters at the end reflect software upgrades and are backward compatable. You can substitute a part with "later letters" (D,E,F for example) for one with "earlier letters" (A,B C) but not the reverse. This might help you expand your part universe search on eBay.

The above notwithstanding, I've had modules rebuilt with great success. One advantage is that you know, for sure, the part was specified for the car. Quality rebuilders offer a warranty greater than OEM in my experience.

 

SPIJohn and Spurlee, do you have rebuilders that you could recommend. I found one in Florida, ECUdoctors, and another ECMdepot. in Texas. I was thinking of using the ECUdoctors as they were very responsive in communicating info and called when they had not received my ecm after thinking that I had already mailed it, when I had not. I havn't quite decided whether to have it rebuild or try to find a used one on eBay or some other parts outlet. I like the idea of a rebuilt and knowing that I've got the part that came out of the car.

 

Are you absolutely sure about that? Can you please elaborate on this more?

If true it would be great, especially for the XKR owners, as there are a lot of XJ8 ECU units around starting with LNF1410, but only very few fro a XKR.

 

This was explained to me by one of the tech guys here on the forum. He and I were sorting through some issues with my XK8 and I was thinking about locating a used part. It was pointed out to me that in terms of compatabiity the prefix letters and digits must match exactly. The trailing letters represent "versions" of the part and are backward compatible.

Thus, in the situation here, his part number LJA 1410 AK must be replaced with LJA 1410 XX. It could be suffix "AL" or "AM", etc. but not "AB" or "AC".

Having said all that, I would NOT have expected the part ID to interchange between XKR and XJ8 models; that just dosen't seem logical! Perhaps someone with more knowledge can correct or confirm my understanding...

Rebuilders come of all types. Talk to them and get a sense of their knowledge and buisness. Unless you are in a rush, opt for having your specific part rebuilt and returned rather than the core/exchange method.

 

I already have a 2nd unit (always good to have), so it is more for others. That said I don't mind to test it out if someone has a LNF1410Bx ECU (used in NA cars), my car is from the LNF1410Ax series.

 

m_vrik, the rebuilder that I used was Automotive Scientific, Inc., a.k.a "ASI", located in Rogersville, TN. Their website is www.autoecu.com. As I recall, it cost me $385 for the rebuild with a 3-year warranty. These guys were very easy to work with; they answered all my questions over the phone before I sent my ECU to them. Got it back within about a week, just as they promised. I highly recommend them. Good luck!

John

 

SPIJohn: Thanks for the ASI contact info. I remember talking with them also. I think that my concern was that their cost of $385 was so much less than the $575 of ECUdoctors and others in that price range, that perhaps there was something wrong with their quality. I know that is crazy to think that just because you pay more that you will get a better outcome. Thanks again! I think that you just saved me $200.

Larry

 

Well I just got word that my ecm was repaired and being shipped out. I decided to go with Specialized ECU Repair located in Oakland Park, FL. The cost was $575 and tax for shipment to a Florida location. I will be traveling to Florida next week and installing the ecm at that time. I will let the forum know what happens - hopefully starts up, but we will see. The folks at ECU Repair were very good in communicating when my ecm arrived, repaired and shipped out. The repair summary was simply bad capacitors and corrosion which were replaced, cleaned and covered by a five year warranty. Turn around time was one day so they either weren't very busy or it's an easy repair. The reason that I went with ECU Repair was that I will only be in Florida for a brief time and if I need to return the ecm, I can drive to their facility. Keeping my fingers crossed.

 

Well I am trying to reinstall my ecm, but I have a new problem. When my xk8 was towed back from the dealer with a dx of bad ecm, they did not replace the ignition coil hold down bolts or ignition coil cover. I thought that it would be simple to just screw in the ignition coil hold down bolts but the top bolt for each coil seems to need the end of the wiring to be removed from each coil so that the bolt can be screwed down flush. How do you remove the wiring"plug?" I have tried gentle pressure with the end of a screw driver but was afraid of breaking something.

 

There is a small, c-shaped wire clip holding each connector on place. The two ends of each clip have a small bend in them.

These clips must be removed first...a small screwdriver applied to one of the clip ends will do it.

 

Thanks to The Coupe, your suggestion and viewing pictures of the ignition coil on the net helped me to figure out that my coils have a plastic lever that had to be depressed to disengage the wiring from the coil. Have all of the coils secured, coil covers bolted down, and the ecm installed. The jag started right up and seems to be running fine. I have driven it for several miles with no problems. Although, it cost $575 to have the ecm repaired by Specialized ECU Repair, I am very pleased with their service and would work with them again. Thanks for all of the help from the forum.

 

Hmmm...sorry if I led you a bit astray, but your car and mine are both 1997s and I definitely have the wire clips at each coil / harness connector.

Glad you got it all sorted out, though, and good to know that ECM repairs can work. We'll all be there eventually!

 

I appreciate your reply and it just made me look a little closer.

 

My 97 also has (had) the plastic latch. Unfortunately, most of the broke when depressed so I put a dab of HT RTV on the joint after pushing them on. No problems after 2 mo. but I'm not pleased by this quality issue.
RJ_____________
97 XK8 85K mi