Hi guys,

I have a 1988 Jaguar XJS 3.6 manual. When the engine is cold it start without problem. I use the car for 20 minutes and then i try to start it again but the car only start’s at third try, then it run perfectly.

Why the car only start’s fine when engine is cold?

 

Most likely fuel evaporation in the injector rail. Pump a bit tired maybe, FPR ditto? Does it start when hot better with your right foot on the floor?
Greg

 

Maybe is that, i removed the injectors rail 3 weeks ago and i did the injectors maintenance. But i don’t understand why it has that problem now.

What i have to do to solve this problem?

 

Are you saying that this hot starting problem appeared only *after* you removed the fuel rail and injectors?

If so, I'd go back to areas you were working in and look for any wiring or connectors that might have been disturbed.

Cheers
DD

 

One possibility, of many, is a mixture control problem.

The system is designed to provide a rich mixture when the engine is cold. Cold engines love the rich mixture; warmed-up engines hate it ! So, if the control system is faulty and giving a constant rich mixture then the engine would start fine when cold but be difficult when warm. I think Greg was thinking along these lines when he mentioned putting the throttle right to the floor, as doing so clears a flooding condition.

Most often a problem of this nature is caused by a faulty coolant temperature sensor.

Cheers
DD

 

Where is the sensor?

 

I did that but i couldn’t find anything wrong in my work area.

Like you say i think is fuel evaporating on injectors rail but why?

What do you think i have to do?

 

Looks like item #9 in the illustration...located on the thermostat housing

https://www.jaguarclassicparts.com/u...hose-3-6-litre

Personally I don't think fuel evaporation is likely to be an issue after just 20 minutes of driving. I'd think that would occur only after long drives and/or unusually hot conditions. Just my opinion.

Cheers
DD