TVR Griffith 1992 stalling

TVR Griffith 1992 stalling

Author
Discussion

Arjen Fokko

Original Poster:

6 posts

12 months

Sunday 19th March 2023
quotequote all
Hi,
I have since several years a BRG TVR Griffith 1992 4.0 litre
When cold, she starts without problems, but when she has done some miles (getting hot) when you brake for a bend and then, in second gear, re-accelerate she hesitates and sometimes even stalls. However the motor coolant temperature remains correct.
Idle stepper, injectors, depression unit, airflow meter, spark plugs, leads, distributor all new
Can someone help me out and may be do a miracle?
Thanks a lot for any advice

s p a c e m a n

10,752 posts

147 months

Sunday 19th March 2023
quotequote all
I would first recommend buying one of these which may narrow down the fault..

https://www.ebay.co.uk/itm/314414131366?mkcid=16&a...

Arjen Fokko

Original Poster:

6 posts

12 months

Sunday 19th March 2023
quotequote all
Thanks a lot,
I will try this

RobXjcoupe

3,151 posts

90 months

Sunday 19th March 2023
quotequote all
I had hesitancy issues with my 95 500 when hot and it was the ignition amplifier. Changed that and it was all good

tivver500

369 posts

269 months

Sunday 19th March 2023
quotequote all
My 500 was running fine and then died. Still had a spark (but apparently too weak) but wouldn't start when hot.
Started fine when cold though.
Was an easy fix as the coil was breaking down when hot. It actually rattled when shaken!!

As you haven't mentioned it worth swapping the coil.....

Arjen Fokko

Original Poster:

6 posts

12 months

Monday 20th March 2023
quotequote all
Thank you all for your valuable advices
I will keep you posted
Greetings from a rainy Belgium

Greg M

81 posts

170 months

Tuesday 21st March 2023
quotequote all
I will second the ignition amplifier... I suffered the same sort of symptoms - plus wouldn't restart until it had cooled - and replacing the ignition amplifier resolved the problem immediately.

Teamred

31 posts

60 months

Monday 3rd April 2023
quotequote all
I reckon your coil is on the way out. Because they're mounted horizontally they can loose their oil and start to break down when they get hot. Top of the engine and horizontal is a crap place for a coil!

Arjen Fokko

Original Poster:

6 posts

12 months

Sunday 16th April 2023
quotequote all
Hi,
Changed the coil and the ignition amplifier.
The take up from low RPM is definitely better but after fine driving she stalled when stopping for a road crossing, and had some troubles to start her again.
Other brilliant ideas?
- Do not stop for road crossings?
- Bring her to the doctor

Thanks for your input


lancepar

1,011 posts

171 months

Sunday 16th April 2023
quotequote all
Arjen,

Has the stepper motor been cleaned lately?

I wouldn't hurt to give it a clean, easy job.........

https://www.gomog.com/allmorgan/StepperMotor.htm

You might find some help on the above link regarding the base idle setting and the fuel temperature sensor.
.
If you need to check the throttle pot, there is a section in this link......

http://www.v8engines.com/carbs-2.htm#setting-up

HTH
Lance
cool


Hoover.

5,988 posts

241 months

Monday 24th April 2023
quotequote all
Is there a strong smell of petrol ??

Arjen Fokko

Original Poster:

6 posts

12 months

Monday 24th April 2023
quotequote all
No, no smell of petrol

blaze_away

1,502 posts

212 months

Monday 24th April 2023
quotequote all
Have you set the base idle ? Set by adjusting base idle airscrew. Approx 700rpm with the idle bypass hose clamped shut.

Have you checked for vacuum air leaks with a smoke detector. ? A vac leak could be present when cold allowing higher revs to be acheieved which closes up as engine warms up thus restricting the air flow reducing revs.

bergxu

381 posts

156 months

Wednesday 24th May 2023
quotequote all
Don’t forget you’ve got the speed sensor from the rear diff that sends a signal via the speedo to the engine management. Could be your issue if stalling at junctions.

ESDavey

700 posts

218 months

Thursday 1st June 2023
quotequote all
I had previous issues with poor running due to the AFM (air flow meter) being contaminated. Try unplugging the AFM and see if that fixes the problem. Simple to try.

PreCat Griffith

62 posts

5 months

Sunday 17th December 2023
quotequote all
Hoover. said:
Is there a strong smell of petrol ??
Sorry to drag up an old thread, but my '92 Griff also cranks for ages before starting when warm (fine when cold) and also smells of fuel (including on the dipstick and inside the rocker cover); what advice would you have given please?

blaze_away

1,502 posts

212 months

Sunday 17th December 2023
quotequote all
Get yourself RoverGauge and then let's talk about what the data is telling you. Could be many things like temp sensor , MAF, Vac Leak, ignition spark and or timing etc etc.

blitzracing

6,387 posts

219 months

Monday 18th December 2023
quotequote all
PreCat Griffith said:
Sorry to drag up an old thread, but my '92 Griff also cranks for ages before starting when warm (fine when cold) and also smells of fuel (including on the dipstick and inside the rocker cover); what advice would you have given please?
Check the fuel rail and water temp sensors have the same resistance when cold- they are electrically the same so should give the same reading.

Check the AFM standby voltage- the voltage goes up as the AFMS fail and also get more affected by heat. This over fuels the engine.

Testing is performed in the following manner. Peel back the rubber boot on the airflow meter connector and leave it plugged in to the airflow meter. Set up the digital multimeter to read voltage. Insert the negative probe into the Red/Black wire (sensor ground), and the positive into the Blue/Green wire (Airflow signal).

Turn on the ignition, but do not start the engine. The meter should immediately indicate a reading of approximately 0.3-0.34 Volts after the initial "warm up" spike. Most defective airflow meters will overshoot to 0.8 Volts or higher, and take at least 2 seconds to come down to the correct voltage.

This .3 to .34 volts is critical to get the AFM voltage correct across the whole air flow range.

If you have RoverGauge, put the AFM reading in direct mode, then just blip the starter but not enough to start the engine. This will make the ECU read the AFM standby voltage and should read 6% if all is well.


PreCat Griffith

62 posts

5 months

Monday 18th December 2023
quotequote all
blaze_away said:
Get yourself RoverGauge and then let's talk about what the data is telling you. Could be many things like temp sensor , MAF, Vac Leak, ignition spark and or timing etc etc.
I do actually have Rovergauge, but it's no longer connecting...that's another problem.

PreCat Griffith

62 posts

5 months

Monday 18th December 2023
quotequote all
blitzracing said:
Check the fuel rail and water temp sensors have the same resistance when cold- they are electrically the same so should give the same reading.

Check the AFM standby voltage- the voltage goes up as the AFMS fail and also get more affected by heat. This over fuels the engine.

Testing is performed in the following manner. Peel back the rubber boot on the airflow meter connector and leave it plugged in to the airflow meter. Set up the digital multimeter to read voltage. Insert the negative probe into the Red/Black wire (sensor ground), and the positive into the Blue/Green wire (Airflow signal).

Turn on the ignition, but do not start the engine. The meter should immediately indicate a reading of approximately 0.3-0.34 Volts after the initial "warm up" spike. Most defective airflow meters will overshoot to 0.8 Volts or higher, and take at least 2 seconds to come down to the correct voltage.

This .3 to .34 volts is critical to get the AFM voltage correct across the whole air flow range.

If you have RoverGauge, put the AFM reading in direct mode, then just blip the starter but not enough to start the engine. This will make the ECU read the AFM standby voltage and should read 6% if all is well.
Thanks for such explicit instructions; I'll get on to this!