Hello my jag has some starting issues sometimes . It cranks and has fuel did a fuel pressure check but say like 6 out of 10 time it does not start up right it takes a few seconds now ive read some posts about problems like jags that dont start what ever you try but mine does start but takes a while. And sometimes starts up right away no problem i've read something about a theespoon of oil in each sparkplug hole to restore compression by gummed up oil seals what is this about and does it hurt to give it a try ? Thanks guyss !!

 

How long is the car sitting between startings? Mine has always been *very* finicky if left to sit more than 4 or 5 days between startings. I think I may have a leaky fuel injector, which has caused the car to be hellishly difficult to start when it does the fuel injection equivalent of flooding. When that has happened it always takes a few minutes and a few miles before everything settles down back to normal.

This is one reason that I don't allow the car to sit for very long between uses.

I hope you figure out what's up.

 

I drive the car almost every day but mostly around town and short trips so it does not get on the right temp sometimes. So thats why i was thinking about the option of puting some oil in the cilinders. Maybe it would help

 

Or maybe there are sensors i can check ? I dont know witch one's and the location.

 

I think there is a known issue with the fuel pump check valves out there. My 01 XJ8 would start hard and stumble/shake for a few seconds before it smoothed out. It wound up being a bad check valve inside the fuel pump but instead of changing it out for that sole reason, I plumbed a one-way check valve into the fuel hard line *just* before the fuel filter, and it fixed things right up. Cost me $30-something bucks and maybe an hour's time. Granted, I had access to a shop lift and a tubing cutter I have. (Normally for cutting brake hard lines

 

Ok these check valves what do they do ? Keeping pressure ? Can i check if these valves are working ?

 

Don't bother with oil in the plug holes, that's only if it won't start at all. I am confused, you say 97, V8, but in Canada at least the 97s were 6 cylinder.

 

England and possibly Europe were a year ahead. The XK8 was available in '96 there.

 

Yes, it's pretty easy, you just need a simple fuel pressure gauge. Though you can buy a high-end gauge from any tool manufacturer, a cheap one from any parts store should work...I believe the standard Ford adapter will work. You remove the cap from the Schrader valve on the fuel rail and thread the gauge on. After installing the gauge, prime the pump and check for leaks at the gauge. If none are present, note the fuel pressure. If it rapidly drops to 0 psi, start the engine, then shut it off again. It should hold around 35-40 psi in the line after shut-down.

My check valve is faulty and as soon as you turn the engine off, the fuel pressure would drop to zero. The fuel has to be going somewhere, so if it bleeds off, it's either the check valve or a stuck injector.. The check valve is much more likely unless the car is blowing some black smoke, especially on startup, and running poorly.

 

Ok this is not the problem with my car when i shut off the engine the pressure rises a bit slowly to to around 43 psi and then goes back to around 36/37 but takes i think more then a hour en doesnt go under that .

 

Hello guys ,
Back again had to do some work to the jag had a blown head gasket . It is all fixed now but the problem is still there. I have a good fuel pressure good battary new 4 days old 100amps allnew gaskets heads are cleaned and valves are nice and clean all things on the car are good i think. But starting problems stay. Sometimes it starts up good sometimes not so good or fast . And even when i crank it and crank it like 5 to 7 seconds it sounds like the battery is going empty . Makes the low batt noise a but and starts to shake a bit and then it fires up. And getting a trac error that goes away again.

 

At this point it might be worth the time to take all of the power and ground connections apart and clean them. Several members in damp northern climates have reported problems with bulkhead and ground strap connections. Start right at the battery and leave the neg. cable off until you are done.

 

That is a good tip ill put the car up in the air tonight and check all the connections under the car , and engine compartment , battery space.
I hope it will make a diffence.

Thanks

 

Ive cleaned the grounds checked it all but still starting bad sometimes im thinking that the parkplugs not getting spack sometimes seems to me or a sensor not working the way it should

 

My XJ8 VDP had the same problem when I first got it, it started poorly and shook for a few seconds. I found that the check valve in the fuel pump had gone bad, so it would not maintain pressure. To test yours simply hook a gauge up and turn the key from off to Ignition. It should climb to around 30-35 and stay there. If it immediately starts dropping, there is your problem. I was able to avoid replacing the pump by splicing in a one-way check valve in-line on the pressure side of the system, right in front of the fuel filter as close as I could get it to the pump. Fixed my problem 100 percent and cost me about $35 and 45 mins of labor. But I did have to cut the metal fuel line to install it with brass ferrules, like a brake line splice, something only a professional should do.