Cold Start Difficulties

[estine]

I have a 2002 type-S 4.0 that doesn't want to start in the morning or after sitting for a period of time.Our Mech did a reading on the fuel pump and changed it out and it hasn't helped the problem then we were advised to change out the "engine coolant temperature sensor" which we did and still no help.We also listened to the injectors to be sure they were all firing and they seemed fine.Now we are being told to change out the Valve-air assisted injector control sensor.....does anyone have a fix for this problem? Any help would be greatly appreciated...

[danielsatur]

1) How many miles is on this car?
3) Is there any codes being thrown?
3) When she is warm, how is the idle?

Wow!
Lets not just throw parts and service at this car, it's easy to go broke.

Everyone wants to blame the computer, it throws a code, there's a service list of suspected failures...........

If No codes, I want you to drive this car in the city, and Highway for 150-200 miles,
this should be enough driving time to throw a code.

Don't be affraid to go Wide Open Throttle (WOT) a few times on the highway for a short, don't go
over the speed limit, do the low limit/ high limit thing a few times, I want to see how she reacts.

A bad Coil on plug,spark plug,and Injector will misfire and throw codes!

I want to see a code, befor Assuming anything, see fuel incjector check -

http://www.automotiveforums.com/vbul...d.php?t=906693

Can I have your bad fuel pump after the fix?

[estine]

The car has 120000, it idles very good,has plenty of power,no codes that I know of....is my wifes car and she has a heavy foot.Like I said before once the car is started in the morning it starts like it should the rest of the day, as long as it hasn't sat to long.Thanks again for any help...

[danielsatur]

Because of Age + mileage, throwing a part at it, isn't as bad.

What elements do you need for a fire on a cold morning?

Your computer wants to see some signals -
Air temp
MAF sensor
Water Temp (sensor)
Air/fuel mix!
Combustion (Engine running)

Pre O2 sensors sends a feedback signal to the PCU, and ECU on how good the emissions, and how good your Engine is performing, so the PCU can adjust fuel/Air ratio

Whats the most wear & tear, and suspected?
1) Air filter
2) Theres also a air tube from the front L-bank valve cover, this provides breather air to the throttle body during the closed throttle body condition, it needs tobe cleaned, the port hole in the valve cover gets plugged with gunk, use a tooth pic, or a small drill bit for cleaning, but dont drop into the valve cover.
3) 80% Massive Air Flow sensors don't react good, they also canbe cleaned with MAF CRC cleaner,or replace.
4) It's probably time for new up-stream O2 sensors.

[estine]

Thanks once again Danielsatur for your help. I will look into the suggested sensors this Saturday and post what I find . Your guidence has been much appreciated....

[estine]

After cleaning the throttle body and the air mass flow sensor just had the air filter replaced at the time of the oil change, also the air tube from the left valve cover. I then tried to start the car....no luck still didn't want to start. It took four long start cycles before it started.I let it sit a while and it would start up normally.Then I decided to take the car to the highway and once there I floored it, got to 85 in a heart beat no problems did that several times,rpm went 6500 with no trouble
Well I guess its back to the drawing board. Would it be worth the trouble to remove the injectors and check for a leaking one?

[danielsatur]

The symptom of a bad MAF sensor is hard starting.
I wouldn't have a problem replacing it, because 80% of them don't perform good, and the Age and mileage of your car.

It's nothing unusal for these to go bad without throwing a code, I wanted you to try
cleaning with CRC MAF sensor cleaner, because it was cheaper.

Do you know anyone with the same type of car, where you can borrow there MAF sensor for the short?

LOL - I don't think a Jaguar Mechanic, would tell a customer on how to save a buck.

I was hoping, the Ads by Google on the bottom of this page would pick-up a good
place to buy jaguar MAF sensors.

http://www.discountairintake.com, It's around $100 new,and it's free shipping, I don't think it would be worth the risk to buy a used 10year old part on EBAY.

The MAF sensor will heat the air in the Air duct to the throttle plate,when the throttle plate is close, the Air will get warm, when it's wide open throttle, the Air gets cold.The Incoming Air Control Temp (IACT) will detect this temp change and send a signal to the Powertrain control Unit (PCU) for processing, the PCU will send a signal for the proper Air/fuel mix.

[estine]

I wish I did know of someone with an maf sensor I could borrow but alas no such luck !!!So I went a head and purchased one......errrrrrr again no help this sucker just doen't want to start in the morning!! but it should at least provide some gas milage improvement hopefully :>)...Would you have any other thoughts or suggestions before I put some C-4 to it???
Thanks again ...and be careful drinkin and operating a computer you wouldn't want to have to breathe into an analyser before your allowed to boot it up Cheers!!!

[danielsatur]

Hey! estine
The CRC MAF sensor cleaner worked in this case,see
http://www.automotiveforums.com/vbul...d.php?t=968872