James Pheby
03-10-2013, 08:15 PM
Hi everyone,
I recently bought a coupe, and it was working beautifully initially. As its a high mileage and not recently used car, I decided to service it. New Oil, Oil Filter and spark plugs were fitted, and a mis-matched fuel filter almost went on, but was wrong so couldn't be fitted. After this minor service, I have a very annoying problem...
What I have occurring is that the car starts fine, but after around 5 to 20 seconds, there is a rumble which sounds like a mis-fire and a severe lack of power which progressively gets worse until the car stalls. If the accelerator is pressed anywhere between 1/4 of the way and fully down, the engine seems to increase in rumble-intensity when pressed around 1/4, or stop firing altogether and almost stall when pressed 1/2 way down or more; the inevitable stall can be prevented by releasing the throttle a decent amount if this occurs. Quick bursts of the throttle show an initial delay in engine speed increase, but it does speed up.
What I have checked:
I have changed the fuel pump now, as the original old unit was very noisy, and I figured it was causing issue. A direct electrical feed has been used to ensure the supply is not the problem to it.
A new fuel filter has also been attached, along with new hoses around that area.
HT Leads have been removed 1 at a time, and each one causes an noticeable misfire when removed.
Breather Hoses have been checked/replaced
Electric Multi plugs have had a thorough blast with contact cleaner and corroded spades replaced.
Old spark plugs been re-fitted
On a side note, the cold start valve does not send fuel when the engine is cold :S
Current thoughts to the problem are:
The fuel system needs to be bled somehow - anybody know if this is a known issue?
The vacuum hoses from the rocker cover are incorrectly fitted or damaged
Some demon electrical fault...
Any suggestions would be GREATLY appreciated. Thanks a lot in advanced!
I recently bought a coupe, and it was working beautifully initially. As its a high mileage and not recently used car, I decided to service it. New Oil, Oil Filter and spark plugs were fitted, and a mis-matched fuel filter almost went on, but was wrong so couldn't be fitted. After this minor service, I have a very annoying problem...
What I have occurring is that the car starts fine, but after around 5 to 20 seconds, there is a rumble which sounds like a mis-fire and a severe lack of power which progressively gets worse until the car stalls. If the accelerator is pressed anywhere between 1/4 of the way and fully down, the engine seems to increase in rumble-intensity when pressed around 1/4, or stop firing altogether and almost stall when pressed 1/2 way down or more; the inevitable stall can be prevented by releasing the throttle a decent amount if this occurs. Quick bursts of the throttle show an initial delay in engine speed increase, but it does speed up.
What I have checked:
I have changed the fuel pump now, as the original old unit was very noisy, and I figured it was causing issue. A direct electrical feed has been used to ensure the supply is not the problem to it.
A new fuel filter has also been attached, along with new hoses around that area.
HT Leads have been removed 1 at a time, and each one causes an noticeable misfire when removed.
Breather Hoses have been checked/replaced
Electric Multi plugs have had a thorough blast with contact cleaner and corroded spades replaced.
Old spark plugs been re-fitted
On a side note, the cold start valve does not send fuel when the engine is cold :S
Current thoughts to the problem are:
The fuel system needs to be bled somehow - anybody know if this is a known issue?
The vacuum hoses from the rocker cover are incorrectly fitted or damaged
Some demon electrical fault...
Any suggestions would be GREATLY appreciated. Thanks a lot in advanced!