Power "switching on" at 3700rpm

[redgriff500]

Hi another issue has arisen...

4.0 Chim 1995 - it goes ok but then at 3700 it's like a switch is flicked and it suddenly takes off - what's the likely cause ?

Dizzy ?

Thanks

[SILICONEKID340HP]

redgriff500 said:

Hi another issue has arisen...

4.0 Chim 1995 - it goes ok but then at 3700 it's like a switch is flicked and it suddenly takes off - what's the likely cause ?

Dizzy ?

Thanks

Is your Vac pipe connected ..

My old 4l had the vac pipe disconnected ,it was pretty sluggish until it hit around 3000rpm..

Some engine Tuners set the timing at 3500rpm to give more advance but you loose out lower down and it uses a bit more petrol. There is a slight delay when you first put your foot down ..

[redgriff500]

It wasn't but as this only happened the other day (before the brakes failed) I guess that's a very good place to start looking.

[SILICONEKID340HP]

redgriff500 said:

It wasn't but as this only happened the other day (before the brakes failed) I guess that's a very good place to start looking.

Give it a good suck ! it should stick on your tongue

[redgriff500]

Sorry typo - it was connected last time I looked.

I'll take another look tomorrow

[mrdarcy]

Although not totally knowledgable, I believe from memory that the fuel injection system goes open loop above 3000 to 3500 rpm and then utilises the pure fuel map and not the lambda sensors. Certainly Mr Darcy has Mr Jekyll and Mr Hyde with low down torque and high end oomph. Just my two penneth worth but again makes these cars with character.

[redgriff500]

Vac pipe is connected and sucking.

Step is at 3500 (should that matter)