Wassup Jaguarz!!!! I have another question im just about done with completing my 1988 xj6 project (Motor) before i start on the interior and body work. one problem when i start my jag it chokes for a while and then later catches and starts up with a low idle and later raises idle. I notice da high pitch noise that sounds like its coming from the the fuel pump but im not sure. I tried the fuel injector cleaner techniques and i have a full tune up job done so i just really need confirmation if my guess is right before i get a new one and not need it advice will be greatly appreciated.

 

Did the tune up job include a new fuel filter?

 

Out of evrything i did in the tune up job i didnt change the fuel filter. Maybe thats the problem I hope and will get on it as far as replacing it. If its not the problem do you think i will need a new fuel pump? Answers will be greatly appreciated.

 

Hi Jaguar Dre,

+1 on replacing the fuel filter.

I'm not sure I understand your description that the car "...chokes for awhile and then later catches...." Do you mean that the engine cranks for a long time before it starts? Often this condition is due to multiple components or systems malfunctioning or operating out of spec.

First of all, have you checked the Vehicle Condition Monitor for any stored Diagnostic Trouble Codes (DTCs)? To check, turn the key to Position II (Ignition ON) but do not start the engine. Press and release the VCM button on the trip computer to the right of the steering wheel and watch for a message to appear in the small display window below the speedometer. DTCs will be in the form of FF or Fuel Fail and a number. Write down any message that appears and post it here.

You have so many threads going that I can't recall all that you've done on the car, but assuming you've done all the right things in your tuneup, some of the causes of long cranking times include:

Low battery voltage while cranking (if the voltage falls much below 11V while cranking the ECM will not trigger the ignition to fire)

Low battery voltage at the ECM due to corrosion on battery power connections and/or grounds

Low voltage at starter due to weak battery or corrosion on battery power connections and/or grounds

Failed or failing fuel pressure regulator

Failed fuel line check valve

Intermittent operation of fuel pump relay

Failing fuel pump

Contaminated or failing crankshaft position sensor

Stuck-open Idle Air Control Valve (IACV)

Problems with the ignition coil or ignition amplifier

Problems with the distributor cap or rotor

Low cylinder compression

Stuck-open carbon canister purge valve

Stuck-open EGR valve

Incorrect spark plugs

Problem with a sensor such as the Mass Air Flow sensor (MAF) or Coolant Temperature Sensor (CTS)

Other things I can't think of right now


As far as a tuneup goes on an XJ40, here's my list, excluding things that shouldn't affect starting like oil/filter, windshield wiper insert, windshield washer fluid, tire rotation & pressure check, front wheel bearing check, etc.:

New correct spark plugs (Champion RC9YC / 344)
New spark plug wires
New distributor cap & rotor
New air filter
New fuel filter
Clean engine bay ground points
Clean engine bay electrical connectors, especially the two on the intake manifold and the one on the firewall behind the cylinder head
Clean relay terminals and sockets (disconnect battery negative cable first)
Clean throttle position sensor
Clean Mass Air Flow sensor (MAF)
Check throttle cable for slack and adjust if needed
Clean air intake plumbing
Pull fuel pressure regulator vacuum hose & check for signs of wet fuel
Check or change engine oil, coolant, power steering fluid and transmission fluid; if any fluid is low, check for leaks
Use your favorite fuel injector cleaner in a tank of gas

Cheers,

Don