16v with a mind of it own

my 91 16v has started going a bit haywire the past month, once its warmed up to bout 90C on the oil temp

the symptoms:-

when coasting to a stop, or coming of the gas, the rev counter will start bouncing between say 2k & 4k and it start spluttering misfiring etc, and occasionally the oil light comes on

it will eventually clear itself if allowed sit (still running) for a few momemnt

im totally stumped by what this could be

its not the ISV, it dont work anyhow and has been disconnected for 8mths now

i've cleaned all the earths up, and also cleaned the contracts on ingition unit

also, points etc all cleaned

and it still happens!

anybody any idea at all? it gets a bit embarrasing when it happens!!

Cheers,
Craig
91 16v

 

If your rev counter is bouncing aroung only when it misfires, then something isn't switching the coil on and off properly.

Perhaps a dodgy coil (but these tend to be the last to go). Check the usuals like the hall sender/connector, and the TCI ignition amplifier and related connections.

 

where's the hall sender located?

 

on the dizzy , it`s got a connector with 3 wires sticking out of it.
Edited by: KeithMac

 

ahh, i get ya now, i had the wires of the connector last night giving the contacts a clean up.

i shall investigate further!

 

yeah I'd say hall sender. Happened to me a while ago

 

weird thing is though, it will only happen once the car is at normal operating temp, surely if its the hall sender then it would be happening straight from startup??

is there any known problems with the actual control unit itself?

ive cleaned the switch(TCH) unit contacts up but never bothered with the control unit (forgot about it!)

 

Hmm, may be fueling related. Unless an electrical connection is opening up when it gets hot.

 

think it'll be a case of going over all connections again at the weekend, clean & making sure they are tight

is there a special grease you can use to coat the metal once you've give them a rub with wet & dry?

the thing has never missed a beat in its life, but i made the mistake of gettin a steam clean in the summer & since then everything has basically taken its turn to go tits up.

 

hi, have you found your problem yet??? Im having the same problem with my mk2 1.6, its got a figgin mind of its own, and i can agree with u on that one, its bloody embarrassing!!!

 

Hall sender will break down when hot rather than cold.

 

is the hall sender easy enough to change?

i presume the rotor arm has to come off, but is it just a case of undo a few screws to get the hall sender out?

Dips, i aint doing anything to it till tomorrow