Discussion
On my Griffith 500.
I recently changed the battery - since this, I have had a small, irritating problem.
When accelerating hard, it gags/stutters then revs. It will then stall whilst driving, seemingly running out of petrol.
To help in the diagnosis of this problem I can now give the following info...
I just kicked her up in the garage, just to warm her up and to keep her alive.
Whilst sitting, waiting, she stalled of her own accord after running steadily on tickover for 5 minutes. Immediately after she stalled, the noise of the fuel pump could be heard buzzing for its normal length of time.
Does this give a big clue to the current small but highly irritating problem?
I recently changed the battery - since this, I have had a small, irritating problem.
When accelerating hard, it gags/stutters then revs. It will then stall whilst driving, seemingly running out of petrol.
To help in the diagnosis of this problem I can now give the following info...
I just kicked her up in the garage, just to warm her up and to keep her alive.
Whilst sitting, waiting, she stalled of her own accord after running steadily on tickover for 5 minutes. Immediately after she stalled, the noise of the fuel pump could be heard buzzing for its normal length of time.
Does this give a big clue to the current small but highly irritating problem?
Can you hear a hissing sound after she cuts out? If you leave it a few minutes is it ok again for a short while?
I had a similar problem and it turned out to be a vacuum in the tank. The wax I had lovingly applied had set in the pinhole breather. OK, so it was a motorbike, but the symptoms were similar. I would check any fuel breathers for obstructions.
Could it be blocked with a chip perchance?
I had a similar problem and it turned out to be a vacuum in the tank. The wax I had lovingly applied had set in the pinhole breather. OK, so it was a motorbike, but the symptoms were similar. I would check any fuel breathers for obstructions.
Could it be blocked with a chip perchance?
FunkyGibbon said:I'll put that on the list of things to check.
I had something like this on my chim450. Replacing the coil and the ingnition amplifier cured the problem.
FG
BliarOut said:Its not hissing -
Can you hear a hissing sound after she cuts out? If you leave it a few minutes is it ok again for a short while?
I had a similar problem and it turned out to be a vacuum in the tank. The wax I had lovingly applied had set in the pinhole breather. OK, so it was a motorbike, but the symptoms were similar. I would check any fuel breathers for obstructions.
BliarOut said:- No. I only cook the chips in oil, not petrol.
Could it be blocked with a chip perchance?
lazyitus said:
Immediately after she stalled, the noise of the fuel pump could be heard buzzing for its normal length of time.
Are you saying this happened without you turning the key again to start it up?
If so, sounds like the supply to the ecu or ignition (or related earth) is temporarily being interrupted - causing the engine to swtich off, then (perhaps due the the vibration of the engine stalling) the supply is re-established and the fuel pump primes as though the key has just been turned.
I'd check battery connections and ecu multi-pin connector, then the ignition switch
griffter said:
Immediately after she stalled, the noise of the fuel pump could be heard buzzing for its normal length of time.
Are you saying this happened without you turning the key again to start it up? - me say-
If so, sounds like the supply to the ecu or ignition (or related earth) is temporarily being interrupted - causing the engine to swtich off, then (perhaps due the the vibration of the engine stalling) the supply is re-established and the fuel pump primes as though the key has just been turned.
I'd check battery connections and ecu multi-pin connector, then the ignition switch
I think this is nearer to the cause of the problem. Thanks griffter.
The battery seems OK and I only recently disconnected the ECU and re-connected it to see if that helped, which it obviously hasn't.
where will I find the ignition switch?
CALLING MODERATORS Quinny said:
Lazy,
Sounds as though somthing could be coming into contact with the plus terminal on the battery.
as you've been fiddling in the footwell, I'd check that the ecu and any relays etc are neatly tucked outof harms way.
I'll be diving down there tomorrow by the looks of it.
The fuel pump normally should keep running for a second or so after the engine stalls. That's a good sign, and means you can probably rule out a whole load of potential problems in the ignition feed and fuel pump power system. That leaves an awful lot of possilities. Personally I would suspect an ignition system fault so I would start by looking at the state of the HT components, replace anything that looks dodgy, try a spare ignition amp.
If that isn't it then look for reasons for the ECU to be messing up the fuelling: fuel and water temp senders, fuel pressure, lambda sensors (don't think they would directly affect full throttle behaviour but they could send the ECU into fault mode if they are playing up). Air leaks, AFM problems etc might be relevent to idle problems but not likely to cause full throttle problems so I'd leave them to later.
Some things to think about if you want to chase the problem yourself. Often these problems are caused by a combination of things that are not quite right, rather than a single faulty component that will magically make the problem go away. Unless you have a good understanding of how it is supposed to work, sorting it out can be a right pita. You might consider taking it to your favorite TVR specialist/dealer to sort out. They'll probably sort it a lot cheaper, and you can offset their labour costs against the things you break or replace unecessarily while you're trying to do it yourself.
If that isn't it then look for reasons for the ECU to be messing up the fuelling: fuel and water temp senders, fuel pressure, lambda sensors (don't think they would directly affect full throttle behaviour but they could send the ECU into fault mode if they are playing up). Air leaks, AFM problems etc might be relevent to idle problems but not likely to cause full throttle problems so I'd leave them to later.
Some things to think about if you want to chase the problem yourself. Often these problems are caused by a combination of things that are not quite right, rather than a single faulty component that will magically make the problem go away. Unless you have a good understanding of how it is supposed to work, sorting it out can be a right pita. You might consider taking it to your favorite TVR specialist/dealer to sort out. They'll probably sort it a lot cheaper, and you can offset their labour costs against the things you break or replace unecessarily while you're trying to do it yourself.
Ballistic Banana said:
Lazy, If you like I can move it back to TVRGG , I guess someone was doing a bit of tidying up 
Although I guess you have a few answers here now !!
BB
Yeah, may as well leave it here now. Theres enough to be getting on with now. Cheers BB.
greenv8s said:
The fuel pump normally should keep running for a second or so after the engine stalls. That's a good sign, and means you can probably rule out a whole load of potential problems in the ignition feed and fuel pump power system. That leaves an awful lot of possilities. Personally I would suspect an ignition system fault so I would start by looking at the state of the HT components, replace anything that looks dodgy, try a spare ignition amp.
If that isn't it then look for reasons for the ECU to be messing up the fuelling: fuel and water temp senders, fuel pressure, lambda sensors (don't think they would directly affect full throttle behaviour but they could send the ECU into fault mode if they are playing up). Air leaks, AFM problems etc might be relevent to idle problems but not likely to cause full throttle problems so I'd leave them to later.
Some things to think about if you want to chase the problem yourself. Often these problems are caused by a combination of things that are not quite right, rather than a single faulty component that will magically make the problem go away. Unless you have a good understanding of how it is supposed to work, sorting it out can be a right pita. You might consider taking it to your favorite TVR specialist/dealer to sort out. They'll probably sort it a lot cheaper, and you can offset their labour costs against the things you break or replace unecessarily while you're trying to do it yourself.
As helpful as ever 'green'. I think I'll check a couple of the points as listed by the others and then leave it in the capable hands of a specialist as I'm not too hot on self-tinkering.
Thanks alot folks.
I've had a fumble -
I pulled out the ECU and checked the battery terminals and the relays and general wiring down there. All seems OK and tight.
I checked the HT leads and made sure they were all tight, one seemed a touch loose (very, very slightly) on the dizzy cap so I've pushed everything on tight.
Just had a 20 minute run without incident - maybe I unknocked something that I'd originally knocked?
Hopefully it'll be OK for now?
I hate bugs!
I pulled out the ECU and checked the battery terminals and the relays and general wiring down there. All seems OK and tight.
I checked the HT leads and made sure they were all tight, one seemed a touch loose (very, very slightly) on the dizzy cap so I've pushed everything on tight.
Just had a 20 minute run without incident - maybe I unknocked something that I'd originally knocked?
Hopefully it'll be OK for now?
I hate bugs!
Gassing Station | Griffith | Top of Page | What's New | My Stuff