Thread: Sluggish V8

Originally Posted by wolvespaul

Hi all, this morning on my way to work my D1 decided to play up, when driving in drive all seems fine, but as soon as i want to overtake or kickdown going up hill she has no guts, the revs pick up no problem but it just has no go in it, i tried it off the lights in 1st and worked through the gears while putting my foot down, 1 2 3 seemed to have no guts, but as soon as it gets into drive she starts pulling as normal.
I cant really notice a missfire as she seems to run ok in drive.

Cheers Paul

Check the vacum advance on the dizzy,
take the tube off the plentium end and with your mouth see if it holds any suction,
If it sucks air straight through it needs replacing and can make a big difference in power

I have now changed the vacuum unit as old one was gone, it still seems sluggish when i put the foot down, i put it in 3rd on auto and it seemed to be sluggish and miss a beat when it got upto around 65kms when acccelerating and struggled to get anymore speed.

I have pulled off tube from plenum when running and sucked on hose, the revs pick slightly should they pick up much, there seems to be no adjustment on vacuum unit.

Originally Posted by wolvespaul

seemed to be sluggish and miss a beat when it got upto around 65kms when acccelerating and struggled to get anymore speed.

I have pulled off tube from plenum when running and sucked on hose, the revs pick slightly should they pick up much, there seems to be no adjustment on vacuum unit.

How long since a tune up, plugs/leads/rotor/cap?
Are you running LPG or Petrol?

The increase in revs when you suck the hose proves it's now working,
and no you don't adjust the vac advance,
it controls itself through suction from the engine.

Have you had any other engine probs??

All plugs, leads, rotor button etc are pretty new, had no problems till on way to work yesterday, check the vacuum unit as you advice and it was gone, fitted new one today and took of run, still seems sluggish under throttle, feels like a flat spot.

I know nothing about the ZF autos, but do they have a Vacuum valve like some of the older transmissions. Because it seems to have similar symptoms as when the vacuum hose is detached from the actuator. BW35s and older Holden trannys had this.

sorry forgot to say i run it on vortex 95 petrol

So this happened suddenly,


does it seem as though it's starving for fuel?

yes it just started yesterday halfway to work, didnt notice it cruising at 110 ks, but soon as i hit the mountain it very noticable, like i say the vacuum unit was stuffed, starts and runs fine untill you give it gas and then it seems to struggle a bit, never had this problem in the 12 months i have had it.

Seems to be getting petrol ok, if i rev it hard on the drive it sounds good, but under load is when the problem starts.