Need a bit of help diagnosing a problem
Discussion
At the end of June last year I went for a 1100 mile 5 day trip to the Loire Valley in France in my Ginetta. On the penultimate day 2 things happened.
I was just popping off on a 100 mile round trip to some chateau’s when one of the local round-a-bouts had some roadwork’s on it, there was some guy on a moped crawling round very slowly that distracted me a bit. When I got off the round-a-bout I accelerated away and suddenly noticed a ramp where the workers were resurfacing the road. I hit it at about 40mph and felt like quite a bump. I don’t know if this is related to the next problem.
After seeing the sights of France we headed back to the accommodation. About 3 miles from the site there was a noticeable cough from the engine, I took it easy for the rest of the way and checked everything over. I all looked fine. The next day we were heading back to Milton Keynes and the car performed very well until we got near Calais where the cough came back and got progressively worse till it was almost un-driveable.
Back in blighty and the car seemed to start fine but the cough came back after about 20 miles, it would start again when cool but only last 20 miles till it would cough and stall.
Since then the car as stayed in my garage and now I want to get it fixed. It has a 2L Duratec on throttle bodies, MBE ECU, low level wet sump, plug top coils and type 9 box. When it coughs it’s like a misfire and it hesitates, power drops off till it eventually cuts out.
So any of you experts know what the problem could be?
I was just popping off on a 100 mile round trip to some chateau’s when one of the local round-a-bouts had some roadwork’s on it, there was some guy on a moped crawling round very slowly that distracted me a bit. When I got off the round-a-bout I accelerated away and suddenly noticed a ramp where the workers were resurfacing the road. I hit it at about 40mph and felt like quite a bump. I don’t know if this is related to the next problem.
After seeing the sights of France we headed back to the accommodation. About 3 miles from the site there was a noticeable cough from the engine, I took it easy for the rest of the way and checked everything over. I all looked fine. The next day we were heading back to Milton Keynes and the car performed very well until we got near Calais where the cough came back and got progressively worse till it was almost un-driveable.
Back in blighty and the car seemed to start fine but the cough came back after about 20 miles, it would start again when cool but only last 20 miles till it would cough and stall.
Since then the car as stayed in my garage and now I want to get it fixed. It has a 2L Duratec on throttle bodies, MBE ECU, low level wet sump, plug top coils and type 9 box. When it coughs it’s like a misfire and it hesitates, power drops off till it eventually cuts out.
So any of you experts know what the problem could be?
Wild stab in the dark, but the 20 miles from cold before dying, then fine again when cooled... temperature sender telling the ECU to over-fuel?
Got to be either fuelling or electrical, though, and if it's repeatable is should be easy enough to diagnose fro a 'Crypton Tuning' specialist?
Got to be either fuelling or electrical, though, and if it's repeatable is should be easy enough to diagnose fro a 'Crypton Tuning' specialist?
Im not sure of the exact technical term (fuel lock?)... But in the classics section i have heard of people getting something similar to an air lock. Basically, the fuel pipe is near to something warm and it gets hot enough to evaporate the petrol in the pipe and block it, choking the engine. Then when it cools, all is fine until it gets suitably hot again. Maybe the bump moved a fuel line close to something that gets quite warm?
ETA- Vapour lock
http://en.wikipedia.org/wiki/Vapor_lock
ETA- Vapour lock
http://en.wikipedia.org/wiki/Vapor_lock
I have looked at the fuel pipe as it comes out the tank and it looks good. Might check the whole length to see if there are any kinks. The exhaust runs inside the sill and the fuel pipe runs down the transmission tunnel so shouldn’t get hot. A friend suggested that a coil pack might be on the way out.
"Crypton tuning" or similar is fairly useless on modern engines with ecu's & fuel management etc. tho' if your ecu has a diagnostic port (I don't know the MBE system) you may be able to get someone with the right diagnostic gear to read codes from it which may at least point you in the right direction.
What you're describing sounds like fuel starvatiion rather than a lack of sparks, tho' without seeing/driving it it's very difficult to say, if it's fuel starvation then it's possible something has been disturbed in the tank & is now partially blocking the pickup. When did it last have a fuel filter replaced as that is just the sort of thing that will cause it to play up after a distance - similarly if the tank isn't vented properly - you could try leaving the cap off temporarily (assuming tank isn't full enough to spill & providing it's not raining) & see if that effects a cure - or wait until it plays up then remove the filler cap, if you get an inrush of air & it's fixed you'll know why! HTH
What you're describing sounds like fuel starvatiion rather than a lack of sparks, tho' without seeing/driving it it's very difficult to say, if it's fuel starvation then it's possible something has been disturbed in the tank & is now partially blocking the pickup. When did it last have a fuel filter replaced as that is just the sort of thing that will cause it to play up after a distance - similarly if the tank isn't vented properly - you could try leaving the cap off temporarily (assuming tank isn't full enough to spill & providing it's not raining) & see if that effects a cure - or wait until it plays up then remove the filler cap, if you get an inrush of air & it's fixed you'll know why! HTH
Russ Bost said:
"Crypton tuning" or similar is fairly useless on modern engines with ecu's & fuel management etc. tho' if your ecu has a diagnostic port (I don't know the MBE system) you may be able to get someone with the right diagnostic gear to read codes from it which may at least point you in the right direction.
What you're describing sounds like fuel starvatiion rather than a lack of sparks, tho' without seeing/driving it it's very difficult to say, if it's fuel starvation then it's possible something has been disturbed in the tank & is now partially blocking the pickup. When did it last have a fuel filter replaced as that is just the sort of thing that will cause it to play up after a distance - similarly if the tank isn't vented properly - you could try leaving the cap off temporarily (assuming tank isn't full enough to spill & providing it's not raining) & see if that effects a cure - or wait until it plays up then remove the filler cap, if you get an inrush of air & it's fixed you'll know why! HTH
Fuel tank, fuel filter, fuel lines and fuel pump were all changed at the end of 2008 when the Duratec was put in and its only done 1800 miles since. Still worth checking though but dont think its a problem.What you're describing sounds like fuel starvatiion rather than a lack of sparks, tho' without seeing/driving it it's very difficult to say, if it's fuel starvation then it's possible something has been disturbed in the tank & is now partially blocking the pickup. When did it last have a fuel filter replaced as that is just the sort of thing that will cause it to play up after a distance - similarly if the tank isn't vented properly - you could try leaving the cap off temporarily (assuming tank isn't full enough to spill & providing it's not raining) & see if that effects a cure - or wait until it plays up then remove the filler cap, if you get an inrush of air & it's fixed you'll know why! HTH
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