- XJ Saloons Forum -

1985 XJ6 " FUEL"

Marco Garcia
*

forum user since 2011-09-02

 


Hello all. I have a 85 XJ6 and i live in Henderson Nevada where the temps now are 105. Last month the car is acting like it's staving for gas. I've checked several things and it's mind bogeling.

I just heard today from someone that 1983-1987 have problems in high heat due to how the gas line runs.????
Please Help.

Thanks Marco



1985 XJ6

William Pritchard
Jaguar Owners Association of the Southwest *

forum user since 2010-09-16

 

The fuel filter may be clogged. The gas line may also be vaporizing the fuel near a hot spot in the fuel line, but since it just started I doubt it.



Bill Pritchard
2004 XJ8, 2009 XK

1985 XJ6

Doug Dwyer
Jaguar Car Club of Victoria *

forum user since 2007-03-28

 

Marco, are you sure it's a fuel problem? What things have you already checked? How and when, exactly, does the problem occur?

Tp prevent vapor lock there is a fuel temp switch on the fuel rail that allows max fuel pressure if the fuel gets too hot. It's brown plastic and has two vacuum hose. Is it hooked up?

The ignition moduel and coil are both known to give trouble in high heat situations. Sometimes the symptoms feel like fuel starvation.

With some more details we might be able to narrow this down.

Cheers
DD

Doug Dwyer
Longview Washington USA
1995 XJR

1985 XJ6

Marco Garcia
*

forum user since 2011-09-02

 

Thanks William and Doug. Well lets see, it started a bit over a month ago, when the weather started to get hot now that i reflect back. It acted like it was was a bad miss or ignition. I put new cap rotor plugs made sure i had spark checked plug wires. still not running right. I can get it to run if i feather the gas pedal, however if i try to idle or step on the gas it runs really rough and dies. two years ago all the fuel was dealt with. ALL New relays, new fuel pump filters all are the ggod stuff or proper replacement i.e bosch fuel pump etc.

On Friday a man came by to admire the Jaguar in the garage said he had an 86 XJ and that he found out through alot of calls and heartache that 83-87 have problems with running properly in the heat due to how the fuel runs through the air conditioninf system. Hummm.So I've looked to you all for some experienced support.

Where is the fuel filter?
What is the filter like item in the engine compartment off the fuel rail? Is that a regulator or filter?
Any help on how to check if its coil or the ignition booster amplifier?
HELP Mr Bogeled
Thanks.



1985 XJ6

Robert Sheridan
Jaguar Owners Club, Inc. *

forum user since 2008-07-19

 

Why not take it to a qualified Jaguar mechanic and save yourself a lot of grief? It could be a lot of things. A "good Jag mechanic" can usually diagnose the problem fairly quickly and provide you with a repair estimate before he actually starts the repairs. Just my thought.

1952 XK120
1986 XJS
Owned:
1933 SSI
1951, 1953 XK120
1956 MKI
1956 XK140
1964 MKX
1969 XKE

Re.: 1985 XJ6

Marco Garcia
*

forum user since 2011-09-02

 

Edited on 2011-09-04 15:59:52

Ahhh Yes Robert. Thank you. I do have a really good Jaguar mechanic about 40 miles out, however, when i heard this fuel/air conditioning issue, my thought first was to come to here at this forum to discuss with actual owners to get some insight regarding what i heard first. Thi is my first Jaguar, I've been a old corvette and classic chevy owner until now and I learned with my old corvettes to ask around first.
Any other thoughts PLEASE post guys THANKS a million. Marco


Re.: 1985 XJ6

Marco Garcia
*

forum user since 2011-09-02

 

My 85 Sweet Baby



Re.: 1985 XJ6

Marco Garcia
*

forum user since 2011-09-02

 

Another Pic


1985 XJ6

Bill Pritchard
Jaguar Owners Association of the Southwest *

forum user since 2011-09-04

 

A melted catalytic converter, dirt in the fuel system or a bad ignition will all give those symtoms. The igniton normally would work cold but break down after getting hot..

I had the same symptoms on a 79 Rolls and it was caused by dirty gas after I had rebuilt the entire fuel system. Carbs, fuel filter, pump and tank cleaning. After it was filled up it started running poorly. Since I had just completely overhauled the fuel system, I and my mechanic dismissed the thought that the new problem was fuel related. It felt like an ignition problem, but ignition testing proved otherwise. Finally I decided to take the carbs apart again and found the the problem (dirt). Feathering the gas would work because the fuel demand increased slowly, but not enough to drive the car under a load.

A qualified mechanic can eliminate the ignition as a problem with test equipment. The exhaust might need to be removed to check for blockages and fuel flow can checked with pressure gauges and measuring fuel flow from the pump.
The fuel filter (a cannister with an input and output on either end) should be able to be found by tracing the fuel line. On an 1983 XJ6 - Open the trunk and remove the carpeting on the bottom. Lift the wooden cover to access the spare tire. The fuel filter should be located in front of the spare tire in a container bolted to the side of the spare tire compartment.

The actual regulated fuel pressure at the fuel rail, which should be 36 psi. Disconnect the hose to the cold start injector from the fuel rail and use the now-vacant nipple on the fuel rail to attached your pressure gauge

PS The fuel runs through the AC system in order the prevent vapor lock



Bill Pritchard

1985 XJ6

Marco Garcia
*

forum user since 2011-09-02

 

DEAR MR B. PRITCHARD,
Thank you so much for your time and sharing with me your knowledge.
The P.S. was greatly appreciated :)
Got a few evaluations to do now.

Thanks again



1985 XJ6

Bill Pritchard
Jaguar Owners Association of the Southwest *

forum user since 2011-09-04

 

You have a beautiful car. Keep up the the good work.

I believe Jaguars are true works of art.

Bill

Bill Pritchard

1985 XJ6

Marco Garcia
*

forum user since 2011-09-02

 

Thanks Bill,

I've been an Old 50-69 Chevy collector until I started this 85 XJ6 project.
NOW I'M HOOKED :)
Bill, this car is a work of art. The body lines are amazing, the front grill, the bonnet, the curves, the ride are all amazing...
I'm getting aquianted with some of tools here at this web site and found the library section WOW. I can spend several hours washing her , and every time it is a pleasure to enjoy her sexy curves and works of art lines on these babies.
Now looking forward to the learning process to get her running again :) Hopelfully myself, with the suggestions i've recieved here in this forum.
Thx again Bill
Marco



1985 XJ6

David Brown
Jaguar Association of Central Ohio *

forum user since 2012-02-29

 

Have you check the hose connections? I solved the leak problems by replacing all hose connections that connect to fuel injectors and now it runs smoothly. Does not stall anymore. Maybe try looking at it. Yes it can be a royal pain in neck with fuel problems!