Hi all...frustrated here. Poured over the forums before deciding to post.

1999 XK8 with a start then die issue. I have replaced the fuel pump...nightmare job...replaced relays, replaced fuel filter...another fun task, installed a replacement throttle body, and a new battery.

Car starts and runs for about 3 seconds or so and sounds smooth. Then gets rough and dies. Below is a link to a video I shot:


Please watch if you can and advise...

Thanks in advance

 

You must be frustrated. Way more knowledgeable folks will jump in and help but that error message incorrect part fitted, reminds me of a string someone posted about installing a rebuilt throttle body. They got that message too. One in a million, but why not: is all ok around your throttle body? Wires connectors etc.

Can you get it to run longer if you feather (pump) the gas pedal?

Can you capture any fault codes?
John

 

Check out these two video's posted on YouTube dealing with the throttle body. The first is an overview of the throttle body assembly with very good general information and procedures that need to be followed when dealing with the throttle body, and common problems encountered during installation of a re-manufactured throttle body.

The second video is of an owner, who like you, has had his throttle body re-manufactured, and had problems on the opposite side of the spectrum in respect to the car's idle; too high in his case, too low in your's. His practical solution may be what needs to be adjusted on your car. By following the first video's procedures when dealing with throttle bodies in general, i.e. hard resets between each step, and the second video's adjustment, you may be able to get your car up and running. Good Luck, this problem has plagued you far too long.

First Video Link:
Second Video Link:

 

Frustrated is an understatement!

Regarding the throttle body...watched them and thank you for the reference.

I am suffering the same symptoms as with the re-manufactured one I removed.

All wiring and connectors seem fine and when I hit the gas, nothing happens.

The "Incorrect Part Fitted" message was present from day one...meaning from the day I got the car and put in a new battery. Upon starting this morning...a small miracle...that particular message was no longer displayed. Quite clearly someone else has been screwing with things.

I did pull the codes and here is what I got:

P0351, 0352, 0354, 0355, 0356, 0357, P1367, P1637, P1642 and P0706

Hard to believe coil pack failure with the car running smoothly.

There is definately something up transmission wise because sometimes it will unlock and allow me to move the shifter...usually on initial startup, but after its running, its locked in place.

And naturally there's No power when I moved it back and forth in the driveway.

Here is another video from this morning at about 7am:

 

 

I would say reset the codes and see what comes back.

Gus
www.jagrepair.com

 

Thanks Gus...I did and they all came back...same codes less one coil misfire

 

Have you re-assembled your shifting console. I ask because there is a ground strap in there that maybe did not get re-connected. Likewise check for ground issues at the electronic components you most recently worked on. I remember a post not too long ago about gauges not working; it had to do with a transmission switch of some kind, or switch near the transmission, in that tunnel, I will see if I can find the post, and if it applies to your situation with the gauges.

 

I am sure you already have, but have you done a "hard reset"?
The one with disconecting battery and connecting the + and ground cables for 30s or so.

I am just thinking about if the changed throttlebody have a "zero throttle value" that is lower than the throttlebody before and that after the few seconds of high idle after start the drop to normal idle makes this throttlehouse close the trottle to much.

I think that is something the ECU re-learns after a "hard reset".

And, have you tried with your old throttlebody?
(or was the replacement deal that you needed to send in your old one?)

 

There is an Inertial switch inside the passenger side fuse area. I don't remember if it shuts off fuel or spark, but you might want to check it.

 

Is this an AJ26 or AJ27?

Gus
www.jagrepair.com

 

Good eye Gus...the car is a 99' but the engine was replaced with a newer unit according to the PO. What year exactly I do not know.

Anyway, before I left for work I disconnected the battery. Came home and reconnected and restarted. 1st shot the start/stall came back. 2nd time the car ran but horribly...like REALLY horribly...maybe firing on 4 cylinders. I stopped as I figured I was doing more damage to the cats than needed.

Do the Aj27's have an ignition control module or is it controlled by the ECU itself?

 

On this car there is a mix of coil makes...Denso and aftermarket.

It has fresh bosch platinum 2's in it.

As the XJR and XK8 use the same coil, tomorrow morning I will remove the MATCHING set from my non running (do to head gasket failure) 1999 XJR and install them on the XK8 and see if I still have a misfire issue.

Fingers crossed my 2000 XJR never suffers like these 2...

 

Do the coil packs have 2 or 4 leads to them?

Gus
www.jagrepair.com

 

QUOTE: 'The "Incorrect Part Fitted" message was present from day one...meaning from the day I got the car and put in a new battery. Upon starting this morning...a small miracle...that particular message was no longer displayed. Quite clearly someone else has been screwing with things.' END QUOTE.

QUOTE: 'Good eye Gus...the car is a 99' but the engine was replaced with a newer unit according to the PO. What year exactly I do not know.' END QUOTE.

You need to find out how 'new' of an engine was put into the vehicle. This could explain allot, and should have been mentioned earlier on in your initial post. All kinds of different variables could now be in play. Find out all you can about the engine swap from the Previous Owner, and if possible, talk to the mechanic who was responsible for installing the 'newer' engine; did he mix existing components with new ones. The possible mixture of incompatible components all over the vehicles engine, i.e. original 1999 old control modules mixed with 200? newer control modules, and other electronics that may not be compatible with the new engine.

Although they may plug up together, the older component may not 'drive' the newer type of Throttle Position Sensor, other controllers, and servos properly, or provide the necessary and correct level of adjustments to the newer engine and it's components, or flat out cannot communicate properly between older and newer electronics and modules.

An example of this could be that the original 1999 car's ECU was retained and plugs into the new upgraded Throttle Position Sensor harness, or any other harness, on the newer engine throttle body, which has a different type of Throttle Position Sensor Assembly employed.

Therefore the original ECU would not be able to provide the correct inputs to the newer hardware it is attached to on the newer engine's upgraded Throttle Position Sensor. Without knowing for sure the year of the new engine, and what was done to 'rig' it up to run with what they had on hand, or could not source the proper MY modules to match the MY engine and thought they could get away with re-using the original '99 electronics. Find the numbers on the engine to help track down what year vehicle it came from, and determine what year components are in your car; some may be compatible with the newer engine, but I am betting most are not compatible with the newer engines upgraded hardware. Just a theory.

 

Same question as above, I guess, but has this car ever worked for you? Did you buy someone's project, in a non-running condition? Just trying to figure out how to help you best.

You might want to start by locating the serial number of the engine (basically a date/time stamp on the block) to determine the exact model (AJ26 or AJ27). From there, try and get a sense if the entire engine was swapped out, or just the block, or heads, etc. Triple check if the throttle body matches that engine, too.

It seems like you need to research the exact mix of parts that are in this car right now, and their ability to work together. Maybe you can reach out to the prior owner, or to the shop that did the work for clues.

Best of luck, keep us posted.

 

That is what I was trying to express. The original '99 ECU, or other Modules, trying to drive a newer version of the Throttle Position Sensor, or any other electronic assembly, that was already mounted to the newer engine when it was installed, and is of that engines year. Therefore, there would be a conflict between original components trying to communicate and drive 'newer' hardware already mounted on the engine when it was installed.

Or worse, the mechanic installed the '99 throttle body and other '99 MY 'engine side' components from the '99 engine to the 'newer' MY engine, i.e. put the '99 Throttle Position Sensor on the 200? engine's throttle body, then you have incorrect part numbers to start with, so replacement is a 'bust', especially if you keep replacing parts using the part numbers off the engines existing components because you do not know for sure if they are for a '99 MY, or from the newer MY engine.

Find out the MY of the new engine, from there you can search parts lists and match the numbers to the components on the car, and determine which are from '99 and which belong to the 'newer' MY engine; then replace any '99 incompatible modules and components with the correct MY components. The 'Incorrect Part Fitted' message is trying to tell you this, and will most likely return.

There is also the slim possibility that some of the modules may be able to be re-flashed, once it has been determined which parts are which, by matching the numbers to the parts lists in the STICKY on the post page.

 

I had this issue with a volvo once. Turned out it was the gaspump that was clogged and could not keep the pressure to allow the spreaders to operate as they should. The flow seemed ok when just testing it into a bucket, but when putting on a nozzle it just died.

Check the gasfilter and that you can get pressure from the tank.

Edit:
Saw in your video that you changed all parts. Could it be some sensor that should tell the ECU that the motor is running that does not work, so it simply shuts it down after the initial start engine sequence is complete.

Also if you keep the gas pedal to the floor, it should open the throttle mechanically and eliminate the "bad throttlebody" variable.

 

Did you check the second fuse for the fuel pump?

Link. http://www.jagrepair.com/FuelPumpVoltageChecks.htm

Gus
www.jagrepair.com

 

Hi, did you get this problem solved ? I have the exact same symptoms as you with my 2000 XKR Conv.
JOHN MC England