andymex4481

hi ive got a 1988 xr3i that starts great runs fine but left when hot for 20 mins wont start, it has fuel up to the injection and a good spark but the plugs dont get wet after lots of cranking poss warm up regulater ?
not sure how to test this any one have an idea

andymex4481

forgot to say if left for a couple of hours then starts again???????????

Matt_16v

EDIT, below.

Matt_16v

Probably the starter mate. Sometimes (when they're knackered!) when the engine gets hot it heats up the starter motor and it siezes. Leave it for 20 minutes, the engine and starter cool down, and it works again.

Change the starter and it should be game on!

jamieclements

as above mate , my 1985 series 1 cabriolet did that last year , but as soon as i got a new starter motor the problem stopped

chaffe

If it winds then my money is on so called "dribbling" injectors, as k-jet injectors get old they wear at the nozzles slightly and allow the fuel to boil off and turn gaseous, it then takes a lot of winding to expell the fuel vapour from the injector pipes, and get liquid fuel back to them. Try a new set of injectors in it, they can be had off ebay. This is a common problem, injectors usually last about the 50k mile mark.
http://cgi.ebay.co.uk/FUEL-INJECTOR-...item1c0f496473

andymex4481

cheers for your info dont think its the starter as turns over fine have just got a good second hand w.u.reg and a fuel distribusion unit both make it run better, but leave it for about twenty minutes and it wont start again wait for another two hours and then runs great i wondered if maybe dissy or coil causing a weak spark any ideas please give me a shout

harvcore

iTrader: (8)

i had this problem ,new starter cured it

chaffe

AS i said, change the injectors

chaffe

dont think its the starter

andymex4481

do you know if the starter feeds back to the ignition on maybe a ballast resistor ?
as you can turn it over till the battery goes flat, but wont start till something cools down 2hrs later,
id think injectors would sound like it was trying to start, but it just turns over with no attempt cheers andy

mattxr3i

Ignition amplifier perhaps. The fuel pump gets a signal from the dizzy, maybe the amp has gone when it is hot. Do you get a spark?

chaffe

Take off the fuel feed pipe, key on, wait five seconds and throw a lit match under the bonnet, that will cure most problems

chaffe

thats not true, the fuel pump reylay gets a tach signal from the coil

mattxr3i

If the ignition amp goes you don't get a spark so therefore the coil won't be sending a signal to the fuel pump.

andymex4481

sounds tempting

andymex4481

it does spark when it wont start but the plugs dont get wet
just ordered a new coil and trying to get a dizzy off ebay next thing to ad to the list

chaffe

I still think its the injectors, k-jet is renowened for hot start problems with old worn injectors, more common on golf gti's right enoiugh (as the inlet and ex man are both on same side of head) but still common enough on cvh's.
The way it works is as follows; The injector and whole fuel circuit holds some pressure even when off (there is an accumilator in the circuit). If the injector is worn this pressure drops, and the fuel close to the head starts to boil off to maintain this pressure. If left for a while ALL the fuel in the injector pipe turns to gas (petrol vapour) this will not ignite as it is FAR too lean when injected (and hence your plugs are dry). The car will take some serious winding to dispell all this gas and get the fuel pressure back.

andymex4481

maybe try that got a dizzy and coil on the way let you know how i get on

andymex4481

it aint the coil lol

chaffe

hmmmmmm

andymex4481

its not the dizzy either got to check the fuel pressure readings next

chaffe

it runs when started from cold though? so its not the fuel pump

GVK.

double post

GVK.

Agree, it could be injectors...Also I had a Series one RST about 10 year ago , it had similar fault , it turned out to be the thermo time switch was faulty - you can check the resistance of it vs temperature - I found a chart in Ford workshop manual with all the resistance values vs given temperatures. Worth checking the wiring to it as well.

Good link explaining about k-jet http://www.diagnostic-assistance.co.uk/mech_inj.htm

andymex4481

starts great from cold just read on auto solve that a drop in pressure from pump or the accumulator would cause a hard start problem after 5 -20 mins after engine turned off ,the under bonnet temp rises causing the fuel in the pipes to attempt to evaporate
maintaining the pressure eliminates this problem and eases a good start on a hot engine
sounds like the injector fault you spoke of
i have ordered a new fuel pump as i just want to rule a low pressure fault
out
i noticed the valve on the pump had been removed this made me wonder if the pump is up to the correct pressure so a ew one is a good place to start from

andymex4481

it is a good link it lists the thermo time switch only on cold start not hot, this is why i have not spent any time looking at this does it affect it on a hot start ?

chaffe

put on the new pump first, then if it still doesnt start do the injectors. As you know, my money is on the injectors, when they leak the fuel pressure in the accumulator drops.

andymex4481

new pump fitted ,car starts great from hot at last a result and a garage full of spares lol get em back on ebay thanxs to everyone for there interest and help cheers andy

XR2

You didn't need a new fuel pump. There's a valve on top of it to prevent fuel to be pressed back in to the fuel tank when the fuel near the injector lines get hot and expands.

chaffe

^^^^ as above, there is a check valve in the pump, still its fixed now

andymex4481

the other job of the pump valve is to not open untill a set 5 bar of pressure is reached, this i found drilled out to allow flow regardless of pressure so much for buying a second hand pump ,i think next time i,d be better off with new parts

E980VTJ

can someone explain this to me,the guy bought a new pump and the problem was sorted but then this post says he didn't need a pump,

Mav102387

Hi mate i know this is an old thread but im curious because im having exactly the same problem car starts lovely on cold and even when it is warm if i was to turn it off for a couple mins 2 fuel up etc she starts, its just when i leave it for a while then go bk try and start and i turn her over 8-10 times b4 she fires up? Ta

CAU

I too had this problem on my car. It was the fuel non return valve that is connected to the fuel pump and then the fuel pipe connects to it. It helps the accumulator maintain fuel pressure and stops fuel returning back in to the tank. I too went through the expense of trying many new parts like injectors, accumulator etc. The irony is that this problem was introduced when the previous owner replaced the fuel pump for me before I took ownership and the non return valve supplied with it had no spring and ballbearing fitted.

trackdaymad

When can you buy only the check valve? been on-line and can only find complete fuel pumps? Having similar problems

CAU

e-bay: Fuel Pump Outlet Check Valve

no1fanofcolin

I have same prob with my XR3i when fill up with petrol she wont start, takes couple of mins, also after drive if I turn engine off and start again she prob start first time but not second time if immediately afterwards ... any ideas appreciated

no1fanofcolin

Hi There did you solve the problem? I have the same problem with mine especially after a long drive and filling with fuel, seems hot start prob

no1fanofcolin

Same prob again