Short version:
I played around with the injector pump (IP) and I think the XJ is in a limp mode although the engine light is not on. It idles fine and accelerates as normal up to 2000 RPM and then hits a wall. It will go above 2000 RPM and get to 100 km/h, but it's VERY slow. I'm thinking my issue could be the same as what M84AB1 had in this thread since he was also playing around with the IP:
http://www.ausjeepoffroad.com/forum/...d.php?t=143257
On the last post in the thread M84AB1 said a low pressure side fuel bleed procedure fixed the issue. I can't find this procedure in my service manual so does anyone know exactly what it involves?
Other suggestions are welcome and before anyone asks, I did check the resistance of the no. 1 injector sensor which I think was 108 ohms (did it a few weeks ago now).
Background:
My XJ has had an intermittent stalling issue for a few years now. Hasn't been a massive issue, but obviously I still want to fix it so I had a go....My issue appears to be identical to what vux and a few others described here:
https://www.ausjeepoffroad.com/forum...118385&page=16
The general consensus seemed to be that the stalling is caused by the electronic governor/HDK unit on the VP36 IP. vux fixed his by replacing the whole pump (Pp 13). I wasn't prepared to drop 1k on refurbished IP and I couldn't find a new HDK unit, but I came across an old TDI Golf being wrecked and got the whole IP (VP37) for ~$100, swapped the HDK with the one in the Jeep (appears identical), and after re-wiring the plug and spending some time adjusting the fuel quantity, I got it running pretty well.
The Result:
It drove fine in terms of power, but the stalling issue was A LOT worse to the point where I probably stalled at every second intersection. I played around with the fuel quantity adjustment which didn't make a difference to the stalling. I drove it around for a while like that until it stalled and wouldn't start again no matter how I adjusted fuel quantity.
At this point I rang Bosch Diesel Services in Christchurch. The guy was really knowledgeable and also suspected the HDK unit to be the cause of the original issue. He said that although a lot of these VP pumps are very similar, there are small differences between most of them depending on what vehicle they're in and that's probably why the 'new' HDK unit didn't work properly. I considered taking it to them to get everything sorted, but when he said that it would likely cost ~3k, I decided I would stick the old HDK back in and hope I get back to square one.
I've had this done for a few weeks and I think I've got the fuel quantity adjusted pretty well. Unfortunately, I now have the issue described at the beginning of this post.
2.5 TD in limp mode
Apparently, a number of sensors were showing active faults. Once he cleared them and reset something in the ECU, it went fine. I'm guessing the sensors that were showing faults are meant to send signals to the IP and something I did somewhere along the way with the IP made it think the sensors were faulty. Great to have it running properly again!
