XJ40 ( XJ81 ) 1986 - 1994

Just Bought 94 XJ6 Bad Fuel Pump Relay?

Thread Tools
 
Search this Thread
 
  #1  
Old 10-10-2010, 08:24 PM
fochmann's Avatar
Junior Member
Thread Starter
Join Date: Oct 2010
Location: Lexington, Ky
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default Just Bought 94 XJ6 Bad Fuel Pump Relay?

Hello, I just bought a 94' XJ6 with A Tan interior and green exterior. It was a fantastic car with 48k miles until I went out to the car to try and start it and it just turned over and over. I removed the passenger side trunk panel and located the fuel pump relay above the taillight relay, the taillight relay is a monstrosity if I might add, and removed the tiny fuel pump relay. I jumped pins 30 and 87 according to the instructions in the jag lovers ebook and I could hear the fuel pump running inside the tank, I was happy I don't have to pull the tank. Ok so with the two terminals jumped I tried to start the car and the car will atleast fire now but it will only run for a a second or so then kill out. I can fiddle with the accelerator pedal and keep it at about 600 rpm but it is rather ruff and as soon as I stop fiddling with it, it dies.

My question is do I need a new relay or is something else gone wrong?

I came to the conclusion that I needed to do the terminal jump on the relay because I could feed gas into the throttle body via a hose and it would run.

Thank you for your help.
 
  #2  
Old 10-11-2010, 07:07 AM
MidwestJag's Avatar
Veteran member
Join Date: Jun 2010
Location: Wisconsin, United States
Posts: 1,444
Received 329 Likes on 258 Posts
Default

Fochmann,
You could swap that relay out with a known good one from some other non-essential system as a temporary fix. This would at least eliminate the relay as your problem. It does sound fuel related... and there are all sorts of possibilities as to what could be wrong. Do you have any VCM codes? My very first gut reaction is something to do with the fuel pressure regulator. You should probably test fuel pressure at the rail. Others will chime in. Cheers! Scott
 
  #3  
Old 10-11-2010, 12:54 PM
fochmann's Avatar
Junior Member
Thread Starter
Join Date: Oct 2010
Location: Lexington, Ky
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

What is a VCM code and where can I read them, also what is the pressure suppose to be at the rail?
 
  #4  
Old 10-11-2010, 01:04 PM
fochmann's Avatar
Junior Member
Thread Starter
Join Date: Oct 2010
Location: Lexington, Ky
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

I took the same part number relay above the antenna and put the relay for the fuel pump there and the relay from above the antenna into the fuel pump socket but now the car wont start so would it be some other faulty wiring issue? Where do I start
 
  #5  
Old 10-11-2010, 04:55 PM
fochmann's Avatar
Junior Member
Thread Starter
Join Date: Oct 2010
Location: Lexington, Ky
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

Update, I can run a wire between the two pins 87 and 30 on the relay and the car starts and runs great now, I do not know why it was having issues before.

I have a bigger problem tho, I think I may have a blown head gasket. As the car steams from underneath the hood whilst sitting at a stop light and I opened the hood and there was water on top of the valve cover in the spark plug channel, The steam is only coming from along the exhaust side tho, is whats puzzling me. Do I just need a head gasket or do I have a bigger problem? Help Please

I bought the car as is and the old lady said it ran fine until she went out in the morning to start it and couldn't get it to start.

Well at least it runs now.
 
  #6  
Old 10-11-2010, 07:22 PM
Lumppy47's Avatar
Senior Member
Join Date: Apr 2010
Location: central massachusetts
Posts: 267
Likes: 0
Received 44 Likes on 40 Posts
Default

From your discription it sounds like a head gasket. If its the head gasket what caused it might be plugged up catalitic converters, there are 4 of them one each in the exhaust manifolds and one each in the exhaust pipes.(the ones in the manifold plug up and cause excessive heat and pressure as the exhaust cant get out of the engine,number 2 and number 5 cylinders fail first). So if you have to do the gaskets check the cats before re assembling the upper end.
 
  #7  
Old 10-11-2010, 09:25 PM
fochmann's Avatar
Junior Member
Thread Starter
Join Date: Oct 2010
Location: Lexington, Ky
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

It was definitely the head gasket. I drained the oil and it was watery. There was also some oil like substance in the throttle body.
 
  #8  
Old 10-12-2010, 06:51 AM
fochmann's Avatar
Junior Member
Thread Starter
Join Date: Oct 2010
Location: Lexington, Ky
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

Back to the relay issue, it is not the relay itself it is the wire coming from something that is switched that trips the relay. If I place a volt meter on the terminals I get a constant 12 at the yellow brown, the ground worksn and the big blue red is the fuel pump wire itself. Now, if I have someone crank the car the little blue wire is suppose to be getting 12 volts but it get 1 volt. What is in line that sends the signal to the relay?

Right now I am using the switched wire from the power antenna to run it, probably not a great idea but good enough for testing.
 
  #9  
Old 10-12-2010, 08:04 PM
Lumppy47's Avatar
Senior Member
Join Date: Apr 2010
Location: central massachusetts
Posts: 267
Likes: 0
Received 44 Likes on 40 Posts
Default

check your grounds
 
  #10  
Old 11-21-2010, 07:57 PM
dentree's Avatar
Junior Member
Join Date: Nov 2010
Location: Melbourne Australia
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by fochmann
Hello, I just bought a 94' XJ6 with A Tan interior and green exterior. It was a fantastic car with 48k miles until I went out to the car to try and start it and it just turned over and over. I removed the passenger side trunk panel and located the fuel pump relay above the taillight relay, the taillight relay is a monstrosity if I might add, and removed the tiny fuel pump relay. I jumped pins 30 and 87 according to the instructions in the jag lovers ebook and I could hear the fuel pump running inside the tank, I was happy I don't have to pull the tank. Ok so with the two terminals jumped I tried to start the car and the car will atleast fire now but it will only run for a a second or so then kill out. I can fiddle with the accelerator pedal and keep it at about 600 rpm but it is rather ruff and as soon as I stop fiddling with it, it dies.

My question is do I need a new relay or is something else gone wrong?

I came to the conclusion that I needed to do the terminal jump on the relay because I could feed gas into the throttle body via a hose and it would run.

Thank you for your help.
Consider looking at the crank sensor, although having said that if the crank sensor is bad there should bo NO SPARK and NO FUEL in the rail,(just something for you to investigate as a possibility)
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
toronadomike
XK8 / XKR ( X100 )
66
08-07-2022 03:41 PM
Sprayall
S-Type / S type R Supercharged V8 ( X200 )
13
05-30-2021 08:13 AM
Charlene n John
XJ6 & XJ12 Series I, II & III
3
09-06-2015 11:03 AM
Sprayall
New Member Area - Intro a MUST
8
09-03-2015 07:49 PM
XJsc-guy
PRIVATE For Sale / Trade or Buy Classifieds
0
09-02-2015 11:43 AM

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


Quick Reply: Just Bought 94 XJ6 Bad Fuel Pump Relay?



All times are GMT -5. The time now is 03:37 PM.