Starts ok but dies on throttle opening

[BrianT]

My 400 Chimaera starts well and ticks over fine but when throttle is pressed the engine almost dies. It then doesn't idle very well. When restarted it idles well for a start and then starts to die again. It has recently been serviced by Racing Green and is an everyday car (except tomorrow if I can't get it running again). I can hear the fuel pump running. Any ideas?

[rigga]

Two questions ...
Is this from cold?
How long you had it?

[BrianT]

Rigga, yes this is from cold, I have had this for nearly nine years and have run it most everyday

[BrianT]

Probably should add that this normally runs like a dream. I have just ordered a fuel pump and relays as I had a fuel pump connector issue in the summer although I can hear the pump running it seems a little noisier than usual

[rigga]

I asked because the 14cux is known to over fuel on a cold start, but your second answer indicated its not always done it, I had an issue which exacerbated the lumpy cold start running and it was a dizzy cap at fault.

[BrianT]

Just to put this one to bed. The culprit was a sticky/faulty Air Flow meter. I disconnected it and all was ok, when reconnected it continued to run well. Upon next starting with it connected it was just the same as before (rubbish) and then disconnecting and reconnecting after engine started it runs well again. This will get me by for now until I source a new Air Flow meter.

[EGB]

Lot of heavy rain recently. Flooded roads, spray etc. Has any rain water got passed the air filter and into the well at the base of the AFM . This will affect the sensor and cause odd running symptoms. May save £300.

Edited by EGB on Wednesday 8th January 10:47

[TJC46]

BrianT said:

Just to put this one to bed. The culprit was a sticky/faulty Air Flow meter. I disconnected it and all was ok, when reconnected it continued to run well. Upon next starting with it connected it was just the same as before (rubbish) and then disconnecting and reconnecting after engine started it runs well again. This will get me by for now until I source a new Air Flow meter.

Try cleaning everthing with a suitable electrical solvent. Worth a try before you spend!

[BrianT]

Thanks both of you, it got me to work and back fine today so I will have a better poke around and clean at the weekend

[ianwayne]

BrianT said:

Just to put this one to bed. The culprit was a sticky/faulty Air Flow meter. I disconnected it and all was ok, when reconnected it continued to run well. Upon next starting with it connected it was just the same as before (rubbish) and then disconnecting and reconnecting after engine started it runs well again. This will get me by for now until I source a new Air Flow meter.

I have this symptom. Will try to eliminate the AFM now.

[BrianT]

Hope it works for you too Ian

[QBee]

If you suspect that water might have got into the AFM and the connections to the tube both sides of the AFM are ok, it might just be worth checking that the air filter is correctly attached to the front end of the elephant trunk hose. It's on the passenger side in front of the radiator. Years ago I had a hole in my elephant trunk on a different car, drove through a big puddle and sucked in enough water to blow the engine.

[sapper]

BrianT said:

Just to put this one to bed. The culprit was a sticky/faulty Air Flow meter. I disconnected it and all was ok, when reconnected it continued to run well. Upon next starting with it connected it was just the same as before (rubbish) and then disconnecting and reconnecting after engine started it runs well again. This will get me by for now until I source a new Air Flow meter.

Brian,
If your stuck I have an AFM spare.Works fine but I dont need it.
Took it off in September and was going to put it on classifieds but havent got round to it yet.

[BrianT]

I've got a feeling that this is now cured itself, it has probably dried out. I used the car quite a bit yesterday and drove it to work again this morning, all seems ok. I'll still check it at the weekend though. Thanks for all your advice guys.

[EGB]

Sounds like it was a wet AFM. Engine and exhaust manifold heat has now dried it out. Check filter and trunk as Qbee suggests.

[ianwayne]

BrianT said:

Hope it works for you too Ian

I started it today, disconnected the AFM and it actually ran even worse, so the potential stalling when it's cold on my car is something else.

[EGB]

Try a swop with another working AFM. May indicate a problem elsewhere. Good luck.

[QBee]

ianwayne said:

I started it today, disconnected the AFM and it actually ran even worse, so the potential stalling when it's cold on my car is something else.

Hope not to send you off on a red herring here, but I believe that the gadget that is supposed to control the idle is the stepper motor, which can get sticky if dirty. You can take it apart and clean it. It is located at the back of the plenum.

They can also just go faulty. Mine did, and wouldn't hold any idle whatsoever when hot. All junctions and clutch depressions, other than gear changes, had to be negotiated with three feet on the pedals. Changed the stepper, problem solved.

[BrianT]

Ian, yes I know about the stepper, it wasn't that. It wouldn't even hold revs when throttle pressed. It has been great since i disconnected and then reconnected the AFM.

[QBee]

BrianT said:

Ian, yes I know about the stepper, it wasn't that. It wouldn't even hold revs when throttle pressed. It has been great since i disconnected and then reconnected the AFM.

Exactly - i was telling Ian that I thought he might have an issue with HIS stepper.....