for two weeks theres been a problem with my car,
when the car is cold for 14 hours and I start, it starts slow.
What I have checked and What I have done and replaced to the car in the last ten months is in the list below:
Brand New battery
The starter is good it has good voltage, alternator is good and voltage is good.
fuel pressure is fine 4.5bar as it should be
vaccum is not leaking and neither is oil leaking from anywhere
spark plugs were changed 6 months ago in perfect gap. Coils are fine, cables are fine.
ps for a few days I have noticed that if before starting the cold car I press on the gas pedal and release it and start up, it starts normal
then I thought it might be the throttle position sensor, I then changed the whole throttle body that I bought on ebay. But the problem is still there
I think there might be a problem in Crankshaft
what do you think it could be? What advice can you give me please
The ECU is not giving me a code, when I attach the laptop to ecu everything is normal.
I have had jaguars for some years and have basic knowledge but some things one can get stuck
Did you monitor the fuel pressure when it is cold and starting slow? If it is not retaining the correct pressure, it will have an extended crank.
July, 16, 2012 AT 12:47 PM
Hi thanks for quick reply
first of all I have a permanent fuel pressure gauge and if theres any leakages with in a hour the pressure goes down. It takes overnight for the pressure to go down.
When I put the ignition in on position but dont switch on engine the pressure is perfect. I do not think there is a issue pump.
What I dont understand is when I release gas pedal before start the it starts up fine. It means that after I open and close the throttle body and start the engine its fine but why?
The throttle body is new so what can be the problem,
July, 16, 2012 AT 12:58 PM
Check the idle air control valve. The passage may be carboned up.
July, 16, 2012 AT 1:00 PM
Air control valve is new as you can see in pic attached.
July, 16, 2012 AT 1:10 PM
Ok. Back to my request, what about the actual passage?
July, 16, 2012 AT 2:36 PM
Sorry for late reply
this pictures maybe help you?
July, 16, 2012 AT 2:57 PM
i have attatched photos so you can look at the ecu info at idle. The throttle body and air control valve, I replaced them last week after cleaning them so they are carbon free. Please help, ive had jaguars for some years and do have basic knowledge but here im stuck thankyou
July, 16, 2012 AT 3:09 PM
Only problem is engine (slow cranking about 3 seconds then start) every first time start only
July, 16, 2012 AT 3:18 PM
The last thing I can think of without testing the car myself is the coolant sensor readings.
July, 16, 2012 AT 3:52 PM
Hi thanks for reply, the reading for the coolant sensor is after about 20minutes drive and is normal. The reading is in F not in celsius
one thing I dont understand and its the reason I am chatting to you is: on a cold engine before I start, if I press the acceletator once and then start the engine, it starts up fine. Why is this happening? The throttle body butterfly is completely clean and never gets stuck. I have checked the vaccum, break boot and its all fine. The rpm above is that right?
Could you reply in detail please, thankyou