help engine light on!

[CMF_nick1854]

It's a 1996 1 litre and the engine light is on. Lots of symptoms, sometimes starts OK and runs for 5 minutes and then kangaroos. The cooling fan is coming on when it isn't hot. Latest trick is it starts OK and the revs pulse up and down at a constant throttle opening, as if you are constantly blipping the throttle. I have tried the throttle body resoldering cure without success. I also removed the engine coolant sensor and tested it with a multimeter and it seems to be OK. A fuse labelled INJ (presume injectors) was corroded but cleaned up. Could it air being sucked in through a crack or split? Do ECUs give up? Please help!

Thanks to all the articles on throttle bodies and the like it has been really helpful so far.

 

[CMF_frank2]

nick

have you tried disconnecting the idle control valve, on the front of the throttle body ?, and i would pull the vacuum pipes off and block the spout with my finger (any change in revs would point to a pipe problem maybe)
but the fan coming on might point to one of the coolant sensors eh ?(i think the bigger one is for the fan)
i doubt its the ecu or a crack imo
where abouts are you btw ?

frank

 

[CMF_nick1854]

Thanks for the reply Frank. I have tried disconnecting the idle control valve....in fact i have tried isolating everything I can see that is feeding information to the brain. I had convinced myself it was the engine coolant sensor until I removed it and it tested OK! I suppose the fault could be in the wiring......Are the vacuum pipes the narrow ones say 8mm diameter? I think one feeds into the bottom of the air filter housing, is that right?

I am in northumberland.......long way from Brum and the Queensway.

nick

 

[CMF_frank2]

nick

no not exactly local eh !
mine has a narrow one from the manifold to the fuelrail prv, a narrow one from the back of the t/b to the charcoal res iirc, a fat one from the back of the t/b to the brake servo and a fat one from the manifold to the camcover breather valve
i have had your symptoms before, and it was air ingress
the fan kicking in is wierd tho eh ?

frank