Hello everyone I recently ran into a 86 Jag xj6 VDP not only did i fall i love with everything about this car but its also my first one so its a bit special to me, it sat in a garage for nearly 11 years but only had 13,000 miles on it, after just some general checkups and getting the car running again it became mine, but not for long... a few weeks into having this car i ran into my first big problem while driving on a very busy road the steering suddenly locked up and the gas stopped working luckily i was able to pull into an empty lot, the car refused to start and had to be towed after some time we learned a valve slipped and scratched a piston and head i ended up deciding to get this fixed and it spent a while in the shop i only got it back not even a week or two ago and after i got it back it was running perfect the rough idle it had before was gone and the car overall seemed smoother to drive that is until fast forward to tonight i was coming home after just getting off the highway i hit i decent sized pothole (probably nothing to do with this but any detail may help) and thought nothing of it i get to a red light down the street from my house and all of a sudden i get a super rough idle i figured i was close to home so id just check it out when i got there not even a minute later the steering locked up again and the car up and died, refused to start again (i can turn the key and it cranks but no start there was also a semi quiet "clicking noise" while its trying to start, i ended up pushing it home and heading straight to the forums for research unfortunately its hard fixing a problem without knowing what it could be im hoping its not just the same thing over due to the fact the mechanic we were using lets just say there were some personal issues leading me to believe he may have just done a sloppy job and caused the same thing twice and it would suck to shell out another chunk of cash for what i just had "fixed" looking for any advice in helping me solve this problem im absolutely in love with this car and would genuinely feel a small part of me has died if i have to get rid of it, Any suggestions? truly anything will help. thanks all!!
the steering locked up? or did you lose power steering assist when engine shut off?
( with engine off, steering becomes very hard because there is no power assist from the power steering pump).
but for the steering wheel to LOCK, you have to remove the key from the ignition switch OR turn the ignition switch to OFF.
Something tells me you have a bad ignition switch.
can you clarify what you mean exactly by "steering locked" ?
ahh i may have written the whole thing wrong then, it was the pwer steering as i was able to turn it just very hard although this morning we pulled the spark plug from the bad piston and put a finger over the hole there was no suction or push away we did this to the known good ones and they pulled the finger in it seems this may just be a case of a bad mechanic ruining the car for good what a shame but im open to any other suggestions or what the actual problem may have been that caused this because for it to have happened twice on the same piston even now it has new valves gives me a feeling they did not find the right problem the first time around
the steering locked up? or did you lose power steering assist when engine shut off?
( with engine off, steering becomes very hard because there is no power assist from the power steering pump).
but for the steering wheel to LOCK, you have to remove the key from the ignition switch OR turn the ignition switch to OFF.
Something tells me you have a bad ignition switch.
can you clarify what you mean exactly by "steering locked" ?
ahh i may have written the whole thing wrong then, it was the pwer steering as i was able to turn it just very hard although this morning we pulled the spark plug from the bad piston and put a finger over the hole there was no suction or push away we did this to the known good ones and they pulled the finger in it seems this may just be a case of a bad mechanic ruining the car for good what a shame but im open to any other suggestions or what the actual problem may have been that caused this because for it to have happened twice on the same piston even now it has new valves gives me a feeling they did not find the right problem the first time around
I haven't had my '86 XJ6 long enough to know for sure, but I've had an MGB for decades and once faced the same problem. I had hit a large pothole and the car shut down completely after driving not that much farther. The sudden jolt of the pothole turned off the inertia fuel switch, just as it's designed to do when involved in an accident. I assume XJs have a similar switch somewhere. I'm sure someone here can confirm this if it does. Hopefully it's just that simple.
EDIT:
I looked at my '86 and found the fuel inertia switch...it's much easier to get at than it was on an MGB. Open your right hand front door. It's located right in the open, in the doorjamb, right next to the dash. It's the small black plastic box in the photos attached. You'll see the top of this box has a large semi-circle opening. With a flashlight you can see there's a plunger that will be all the way down to supply power to the fuel pump. A heavy jolt, such as from an accident or even a severe pothole, will turn off the power to the fuel pump. In this case, the plunger will be popped up. If you can't tell if it's up or down, pull it up and then push it back in. Sorry about the poor quality photos. Good luck!
1. Loss of the engine means no power assist to the steering, It gets pretty stiff. Remove that from the issue list.
2. the thumb method of compression measure is a bit rough, but only somewhat useful. Use a proper guage on all cylinders. If you need help on the proper use, let us know.
3. The best guess as of now is a dropped and busted or bent valve. On this engine, the head is an alloy. Hard steel seats are inserted in the head for the valves to seat on. They rely on an "interference" fit to stay in place. Not uncommon for them to drop out of the proper spot and the piston hit the valve. mayhem results!!!
4. Precisely what di the "mechanic' do to affect the repair? .Unless he is a machinist as well with the proper machinery the repair was less that proper...
1. Loss of the engine means no power assist to the steering, It gets pretty stiff. Remove that from the issue list.
2. the thumb method of compression measure is a bit rough, but only somewhat useful. Use a proper guage on all cylinders. If you need help on the proper use, let us know.
3. The best guess as of now is a dropped and busted or bent valve. On this engine, the head is an alloy. Hard steel seats are inserted in the head for the valves to seat on. They rely on an "interference" fit to stay in place. Not uncommon for them to drop out of the proper spot and the piston hit the valve. mayhem results!!!
4. Precisely what di the "mechanic' do to affect the repair? .Unless he is a machinist as well with the proper machinery the repair was less that proper...
More if asked here
Carl
hey guys, so after a bit more testing the car started for maybe a second before dying again to clarify there is Zero compression with that piston i know that the thumb method isnt accurate but it worked with all other pistons except this one it seems unfortunately its probably going to be the valve on the bright side the head had a guarantee on it so if that is the problem we can get it fixed free, im going to go ahead and check that inertia switch aswell although i dont think its a fuel problem but thank you all for the help means alot!
UPDATE, After following the advice of Emily Wojcik (Thank you by the way) the car miraculously started to run but something is very clearly misfiring so i didnt leave it running for long i came back a little while later to try it again and it sat there and idled by itself and didnt turn off i didnt leave this for long as fear that i could make the problem worse by running it very odd stuff.
You're welcome and glad it worked. If you hadn't mentioned the pothole I wouldn't have even considered the inertia switch. It may be misfiring due to the disruption in fuel supply although I don't know how likely that would be, but I think it would be a big coincidence if the car developed an unrelated issue at the same moment the fuel pump shut off. Could the sudden lack of fuel have dislodged debris, clogging injectors? Hopefully others will have a better idea where to go from here.
Hi, I would try resetting the inertia switch first, if it was a valve I think the engine would still run very roughly ---- sounding like someone trying to hammer their way out from the inside. A quick test would be to open the trunk, remove the mat / spare tire cover and have someone stand there to listen for the fuel pump running ( it's under the shelf at the rear / bumper side of the spare tire hole ). You get inside, put the transmission in drive, then turn and hold the switch just like you are trying to start the car. The pump should run the whole time you hold the switch to "start". The starter should NOT engage while the trans is in drive so your helper should hear the pump running, if not then the inertia switch is tripped or there is some other problem with the pump or it's wiring.
Looks like the last two posts were made while I took a break to eat dinner ! It could have sucked up trash in the fuel or maybe the jolt loosened / damaged something else causing the rough running.
hello all this will probably be the end of this thread and i jusst want to thank you all again the inertia switch is seeming to be the killer im sure the disruption of fuel made something slip somewhere and im planning on getting it checked out tomorrow but just one funny little side note to leave you all with, this morning i noticed both fuse panels were removed and thrown about the car i thought nothing of it at first but as the day went on i was sure they were not off last night the wires under my wheel were also pulled out seemingly so someone could try to mess with them.. so yea if i had not had a problem filled jag someone woulda stolen this thing right from my driveway last night just a nice little silver lining about this whole thing at this point im not sure if i hate or love the jaguar gods but im beginning to understand the very "complicated" relationships people talk about when they talk about these cars once again thank you alll for your time and suggestions ill keep you all updated!
