Hot and Bothered p38

dh-t · Jun 8, 2016

As anyone come across this problem.My 2002 RR 4.0 V8 runs fine most of the time but in hot weather it's very differant .If I leave the car parked up in the sun it will start OK but then there is no power and it struggles to get over 5mph then it slowly picks up speed and power over the next 10 milesor so.making it difficult to drive in town.but once on the open road power returnsand it is back to normal until it is parked up in hot sun and it all starts again.Roll on winter.Anyone got any ideas,I've tested the fuel cap and the AFMeter both seen fine.

pete1987RRC · Jun 8, 2016

Fuel pump leaking back to tank?

Doo · Jun 8, 2016

I wonder if it is a fuel vapour problem! Similar to what Pete said.

Switch the ignition on/off a few times to prime the pump and try it.

Definitely sounds like a heat soak issue... Renault 5 turbo's suffered that same issue, but from what I recall, the early ones were carb not injection.

dh-t · Jun 9, 2016

Doo said:
I wonder if it is a fuel vapour problem! Similar to what Pete said.

Switch the ignition on/off a few times to prime the pump and try it.

Definitely sounds like a heat soak issue... Renault 5 turbo's suffered that same issue, but from what I recall, the early ones were carb not injection.

dh-t · Jun 9, 2016

Thanks for your input,I have another thought,the problem always crops up after a run on a hot day,when I park up in the sun.Could it be that the heat of the engine plus the sun on the bonnet{oxford blue} raise the temp so that when I start up the air being drawn through theair flow meter confuses the ecu in some way and it thinks the car is cruising and does'nt put enough fuel into the chambers.Once the car is on the open road and cooler air is being drawn in the engine the problem slowly goes away.Does that make any sence or is it a load of nonsense.

dh-t · Jun 9, 2016

Thanks for your input,I have another thought,the problem always crops up after a run on a hot day,when I park up in the sun.Could it be that the heat of the engine plus the sun on the bonnet{oxford blue} raise the temp so that when I start up the air being drawn through theair flow meter confuses the ecu in some way and it thinks the car is cruising and does'nt put enough fuel into the chambers.Once the car is on the open road and cooler air is being drawn in the engine the problem slowly goes away.Does that make any sence or is it a load of nonsense.

dh-t · Jul 20, 2016

dh-t said:
Thanks for your input,I have another thought,the problem always crops up after a run on a hot day,when I park up in the sun.Could it be that the heat of the engine plus the sun on the bonnet{oxford blue} raise the temp so that when I start up the air being drawn through theair flow meter confuses the ecu in some way and it thinks the car is cruising and does'nt put enough fuel into the chambers.Once the car is on the open road and cooler air is being drawn in the engine the problem slowly goes away.Does that make any sence or is it a load of nonsense.

At long last I took the car to Emmots in Clone,they put it on the computer and it turns out that the previous owner (Dumfries and Galloway police force had put the wrong MAF senior and lambda senior on,not for a Thor 4•0 Ltd but for a Gems 4•0ltr.Emmots changed them and walla a new car,runs and goes like it was intended.all for £134 including labour.

Saint.V8 · Jul 20, 2016

Glad you have a result!

Dopey · Jul 20, 2016

dh-t said:
heat of the engine plus the sun on the bonnet{oxford blue}

Yea I didn't thing it would be the colour of the bonnet..... just saying

Hot and Bothered p38

dh-t

Member

pete1987RRC

Well-Known Member

Doo

Well-Known Member

dh-t

Member

dh-t

Member

dh-t

Member

dh-t

Member

Saint.V8

Dyed-in-the-wool 100% RR Junkie

Dopey

Well-Known Member

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