XJS ( X27 ) 1975 - 1996 3.6 4.0 5.3 6.0

1987 xjsc v12 starts but sputters and hardly idles

Thread Tools
 
Search this Thread
 
  #1  
Old 12-14-2014, 12:31 AM
Falcon1007's Avatar
Junior Member
Thread Starter
Join Date: Dec 2014
Location: Nevada
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
Default 1987 xjsc v12 starts but sputters and hardly idles

Just bought the car and the seller told me it sat for 5 years .
I put in new fuel and a battery . The car turns over and starts but won't run for more then a min. If you put gasoline down the intakes it runs and sounds fine .
Could it be a fuel injection issue . Need help !!!
Anyone have some ideas?? Thx
 
  #2  
Old 12-14-2014, 02:19 AM
Greg in France's Avatar
Veteran Member
Join Date: Jan 2012
Location: France
Posts: 13,336
Received 9,087 Likes on 5,351 Posts
Default

Fuel seems favourite. If it was me, this is what I would do, I think it is a mistake not to work methodically through the suel system on these cars. So I believe the best thing to do is to go through the system from the tank onwards. Under the battery is a surge tank, underneath the boot floor is a rubber bung that gives access to the drain plug under this tank. Remove the battery first!

Undo it and rain the fuel. Then on the surge tank is a locking ring, knock this anticlockwise and remove the outlet spout. On this spout you will see a push-on sock filter. Change this for a new one and clean out the tank.

Behind the spare wheel is the filter. Change this, and then undo in the engine bay the fuel pipe that arrives at the RH fuel pressure regulator (US passenger side). Then blow though this line with some compressed air starting at the filter outlet. Also chack the thick pipe between the surge tank and the pump is free.

Then blow through the line between the main tank and the surge tank. Then undo the return fuel line just after the LH side fuel pressure regulator in the engine bay and the tank and blow though this one too.

If all well and no blockages and a good jet of air coming out, you know the lines are fine. Then put it all together and add a bit of fuel. Now you can test the pump by disconnecting the RHS regulator and pushing a bit of fuel hose over the end and directing it into a container. Ask a friend to switch on the ignition and the pump should run for 2 seconds. Do this a few time to get the system primed, and then see if there is a strong pulse of fuel into you container. If so, the fuel system is OK. If not, then it looks like replace the pump, which is by the surge tank.

If the car does not run, next is the injectors. These have to be tested for electrical feed and for physical blockage. Post again when you get to this point, maybe? But with luck it will be fuel supply.

Good luck
Greg
 
The following 2 users liked this post by Greg in France:
Grant Francis (12-14-2014), pablomonk (12-14-2014)
  #3  
Old 12-14-2014, 06:46 PM
Scoupe89's Avatar
Senior Member
Join Date: Oct 2010
Location: Phoenix, AZ
Posts: 157
Received 19 Likes on 17 Posts
Default

I would drain all old fuel and flush all lines. Fuel volatiles evaporate or gas has gone flat and turns to tar. I would keep changing fuel filters also. I've cut a few open to check the filter paper and always find something. These EFI engines don't like sludge.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Doug
XJS ( X27 )
55
02-27-2019 01:31 AM
Thang Nguyen
X-Type ( X400 )
4
10-12-2015 01:25 AM
giandanielxk8
XK8 / XKR ( X100 )
7
09-06-2015 07:21 PM
Broken_Spanners
XJS ( X27 )
12
09-06-2015 11:34 AM
Bowman
XK8 / XKR ( X100 )
6
09-03-2015 03:17 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


Quick Reply: 1987 xjsc v12 starts but sputters and hardly idles



All times are GMT -5. The time now is 03:14 AM.