Won't start when hot?

Hi 

I have 1982 Golf GTI 1.8 DX engine, the car has just been recommissioned after 8years dry storage, this included new fuel pump and battery, full flush of fuel system and tank (fuel had gone off)!! 

It starts from cold first time, starts a little lumpy but then runs fine, I can run it for 30mins park up, switch it off and it will not restart? I typically have to wait 1hour for it to cool down then it will start again.

To date I have replaced the Coil, leads, distributor cap, rotor arm, plugs and ignition amplifier. With no change it still won't start when hot!!

It was fine before it was taken off the road 8 years ago.

Any advice, guidance or recommendations on this would be much appreciated.

Could be a faulty fuel accumulator letting the fuel pressure drop too quickly when you switch off and what fuel is left in the lines vaporises.

They are pretty pricey to replace, there is a trick to test if it has gone by slackening off the screw at the end of the accumulator (if it's not rusted  in) and if fuel come out it's had it I understand.

I have same issue, started last year, I will get the accumulator changed in the winter, but for now the way to get it to start is to keep the accelerator flat to the floor and churn the starter for about 30 secs and it eventually runs.

It could be the injectors are leaking fuel into the cylinders when you switch off.
From cold it will start then run a bit rough until the excess fuel is burnt, from hot the excess fuel will make it so rich it won't start.
What happens if when hot you turn it off, leave it for just a second or two then try to start it.
 Ideally you need to do a holding pressure test with a gauge.

It could be the non-return valve (check valve) on the fuel pump outlet

Thanks for the replies and the advice, I will get it into garage to have a pressure check carried out. 

When I turn it off after a run it will fire up straight away, but if left it won't start! 

I think one of the injectors has been sticking, so fuel could be leaking round these!! 

I will report back with updates.

Mines the same and it's driving me insane! Had to give up and book it in!

Fuel check valve changed with filter, still the same!

I'm more towards leaky injector or fuel leak.

Can't see it been accumulator as it starts from cold overnight and the accumulator is designed to hold pressure over night, which it is.

Worst case is metering head.

Keep me posted and I'll
Do the same 

I replaced the injectors on mine, made the car run better but sadly didn't cure the Hot starting.

RichardHall said

I replaced the injectors on mine, made the car run better but sadly didn't cure the Hot starting.

 so what was the issue?

 The non return valves stop the pressure dropping. The accumilator gives the system a volume of pressure to stop pressure spikes. You can usually hear the spring pinging as the pressure drops in the accumilator. If the accumilator was faulty it wouldn't run very well rather than being a starting issue.

If your non return valve was replaced on the end of the pump at the same time as the pump then its leaky injectors causing the problem. it has a double whammy effect by filling the cylinder with fuel therefore flooding it and also the fuel pressure drop while the engine is hot causes the fuel to boil in the injector lines above the engine and that plays havoc with the injectors as it replaces the liquid fuel with vapour locks.

When the engine has cooled it loves that little bit of extra fuel that leaked out when the pressure was up so cold starts are fine. I had it with my Camapign that had been stood 25 years. Once I sorted the hot start issue it highlighted the 5th injector wasn't working because I no longer had theis leaked fuel sat in the cylinders waiting for a cold start.
 

H3LTER said

RichardHall said

I replaced the injectors on mine, made the car run better but sadly didn't cure the Hot starting.

 so what was the issue?

Don't know yet, still not fixed, thought it was accumulator but as Yomp has pointed out could be the non return valve.

Hi ,

I have had the same problem ,

I started easily when cold , and when hot with difficulties ,

After having changed pressure accumulator , non return valve on pump line , i solved this problem with new injectors .

If that can helps…………….

If it were the non return valve I don't think it would start from cold easil;y.

I've changed the non return valve, I think it's gonna be injectors, letting my mate pressure test fuel system first 

And that's definitively the best way to put the finger on the problem.