Revs Nosedive When Anything Electric Swithced On ?

[chris 417 mi 35 2 Cars]

As above, as soon as i turn in lights or fans etc the revs suddenly drop and car almost cuts out, it also seems to alternate between 1000- 450 rpm (up and down, is this called hunting? ).

Hear somewhere it could be the alternator??

[M3Evo 0]

Sounds a bit extreme, but it's perfectly normal for the revs to dip with increasing electrical load.

 

The more current you draw from the electrical system, the more current the alternator must provide and the more current it provides, the more difficult it is to turn.

[Pugnut 9 1 Cars]

the 8v injection system has no means of automatically regulating the idle speed where the 16 system does.

 

which do you have ?

[chris 417 mi 35 2 Cars]

This one is the 1.6 8 valve

[DaveK 0]

does the 16v stop the revs dipping under elec loading?

[Pugnut 9 1 Cars]

does the 16v stop the revs dipping under elec loading?

 

motronic engine management has an idle speed control valve which will keep the revs at a pre determined value regardless of the electrical load on the engine. the jetronic management does not have this valve .

[miamistu 1]

Does have an idle control valve, not sure what determines it's actions though.

[Pugnut 9 1 Cars]

Does have an idle control valve, not sure what determines it's actions though.

 

do you mean the 8v?

[chris 417 mi 35 2 Cars]

motronic engine management has an idle speed control valve which will keep the revs at a pre determined value regardless of the electrical load on the engine

 

Wish they had put this on the 8 valve, have to put up with tickover when warm of 1500rpm

[M3Evo 0]

do you mean the 8v?

 

Sure do (sorry, was using Stu's computer and forgot to change users)

 

That kind of disc thing with a 2pin Jr timer connection and two pipes to it is a very basic IACV. (I think)

[chris 417 mi 35 2 Cars]

That kind of disc thing with a 2pin Jr timer connection and two pipes to it is a very basic IACV. (I think

 

Where abouts is this ??

[M3Evo 0]

It's on the cylinder head somewhere (on the dizzy end I think)

 

As I say, it's a disc about 2" in diameter with a 2pin connector and two pipes to it

 

Can't find a piccy of one though

[Ryan 99]

The idle control on the 8v is only controlled by the coolant temperature, to make the car easier to start when cold. It doesn't take electrical load into account.

[M3Evo 0]

Ah haa, fair enough. Tis definately there though, so I'm not going mad

[Pugnut 9 1 Cars]

Ah haa, fair enough. Tis definately there though, so I'm not going mad

 

aah , its called the supplimentary air device (SAD)

[chris 417 mi 35 2 Cars]

Think i may have solved it, id swapped air flow meters over earlier in the week as the one i had on previousley wouldnt let the car go over 4K (just kept hesitating and spluttering etc ) put that one back on last night after i cleaned the SAD and she idled perfectly again !

 

So gonna have a go now at re tracking both meters and see which one is best (hope this works otheriwse im gonna a need a new afm )