CHIMAERA 500 STALLING

[DHUDD]

Hi Guys


Having changed so many parts on my car the stalling fault is still there and is begining to P me off

The problem is it will often stall at a junction or whilst maneuvering. It will even stall if left idleing on its own.

Here is the list of parts I have changed...
Stepper Motor
fuel and engine temp switch
AFM
TPS
Plugs, leads, roto arm,dizzie cap
spark plug extenders
sc plenum spacer with shorter trumpets

I had a chat with Dom at TVR power last week and he seems to think its a green relay interface that is located under the dash but having had the dash off today I cant seem to find mine!?

Your help will be most appreciated on this

Thanks Again

Dave

[blitzracing]

Whats you base idle set at? (Stepper feed blocked off). The ECU does not control the idle (or any of its sensor inputs such at Throttle pot or the green TVR box under the dash) below about 800 rpm. The base idle should be set for around 600 rpm, and the stepper motor and ECU control simply tops this up to around 800 -1000 rpm at idle. If the car is stalling, it could be simply the base idle is too low to start with.

[DHUDD]

Hi there

Idle speed is set as the bible says. I blocked off the stepper feed and set the idle to 600rpm - it will idle perfectly at 900 rpm and then all of a sudden (at different engine tempertures) it will either cut out or the revs go up and down and then it cuts out.

[DHUDD]

Forgot to add

Ignition Amp and coil to that list earlier!!

[miniman]

I went through pretty much the same list hunting down a misfire - turned out to be an air leak between the AFM and the plenum.

[DHUDD]

Thanks for your feedback.
Its not really a misfire as it runs very smooth.
I have also replaced the AFM to Plenum Hose with the uprated Silcone one

Edited by DHUDD on Sunday 3rd April 19:26

[e635815]

Looks very familiar to my issue (see related post on the forum).
Does your rpm needle drop suddenly to 0 at the moment you stall?
And does your fuel pump re-energise right after the engine stalling?

If yes, you have the same pb as mine: ignition cuts out.
Now, the reason why the ignition cuts out is still unknown to me.

More news to come. Watch this space!

[DHUDD]

I must admit i have not noticed the rev counter drop suddenly but the fuel pump will continue for about 4 secs and then stop

[athomp04]

Have you got a vacuum in the tank (created by the carbon canister not breathing propely)? this can be diagnosed by the hiss when removing the filler cap. You can either not tighten up the cap only 3/4, or cut a small groove in the gasket with hacksaw.

[blitzracing]

I would double check for air leaks around the whole plenum area, as these have a much larger effect at idle as the throttle plate is closed off, and the vaccume is high. As already stated anything that lets in air after the AFM will cause it to lean out horribly and die. Worth dropping a plug out to see the colour as well.

[DHUDD]

I by passed the carbon canister today and the fault was still there!

I also checked for plenum leaks today and could not find any!

Its so frustrating

[PRTVR]

DHUDD said:

I by passed the carbon canister today and the fault was still there!

I also checked for plenum leaks today and could not find any!

Its so frustrating

could the leak be from a split diaphragm on the advance and retard, also may be worth checking the connections on the ECU, may be missing the signal that lets it know that the engine is still running, leading to it shutting down the fuel system.

[DHUDD]

(could the leak be from a split diaphragm on the advance and retard)

What part are you talking about here mate?

kind regards

[PRTVR]

DHUDD said:

(could the leak be from a split diaphragm on the advance and retard)

What part are you talking about here mate?

kind regards

There is a small plastic pipe that runs from the plenum to the distributor, on the distributor end is a diaphragm that is connected to a plate that alters the timing when the vacuum drops off, if it was split it may not show up on the normal ways of checking for leaks.

Edited by PRTVR on Sunday 3rd April 22:22

[DHUDD]

do you mean the vacuum pipe from the dizze to the plenum?
If so thats is also been replaced

kind regards

[PRTVR]

DHUDD said:

do you mean the vacuum pipe from the dizze to the plenum?
If so thats is also been replaced

kind regards

that and the part on the dizze that the pipe connects onto, they have been known to split, just thinking you may not have sprayed around that area.

[DHUDD]

I will have a look at that tommorrow, If its split is it common that the engine would cut out tho?

[DHUDD]

http://www.v8wizard.com/faulty-vacuum-advance.php

just came across this so i will have a look tommorrow

regards

[EGB]

I had a similar problem. Solved for me by bridging the B... META imobiliser.
It was intermitently cutting out the fuel pump and or the ignition. Carl Baker (META expert) suggested check that the two relays in fuse box (Silver 1in square boxes with red stripe) are working. Some folks switch the two over. Good luck............Eddie Griff 500

[DHUDD]

Thanks Mate

I will try the relays later.