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Hey,

For a while now my car, 1993 genesis 1ltr Lum MKIII 4 speed has been acting wierd.

Unfortunately it is quite hard to explain, especially for someone like me! but here goes...

When she is idle she will be on like 1000 revs, the longer she is left like that the revs go down and when they get to like 700 she kinda jumps and shots herself back up to 1000,its almost like she almost cuts out and then something brings her back to life.

Thats not a problem but thats the best way I can describe the 'jump' which she also does when i am going at any other speed, usually when I'm revving high, like going 70mph down the motorway, she'll do this wierd jumpy thing like shes gunna cut out and then save herself, she only did it lightly at the start and not very often, and at random times! but its getting scarier, shes also taking longer to recover from her 'jump'and she is doing it more often. And she seems to lose power after the jump.

She also does it when i put my foot down, for example if i get stuck behind something, slow down and then when i get the opportunity to overtake and put my foot down she can do it then, and she just seems to have less (and thats saying something!) tork (sp???)

It really does feel like one day i'm going to be going along the motorway at 70 and she'll just cut out and not recover herself....

anyone have any ideas?? its really odd.

thanks

just to add to what rachel has said.....it sounds like a relay clicks when Lum dies. i haven't had any experience in this but could it be a main relay starting to give up the goast?

does anything else fail? electrics etc? does sound strange. the closest prob ive had was when my g40 would cut out at speed, but this was caused by the hall sender, but your car sounds like it is misfiring aswell, which is something my car didnt do.

She does sort of stall sometimes when I have the clutch down, so you hardly notice, just the battery/oil lights flash and she kinda goes off and then you bring the clutch back up and shes ok again...

Progress - yesterday i was at lights, not doing anything out of the ordinary, I'd have been in gear, and she just died. Started up again fine. hmmm

May just be your plugs/leads need changing, or dizzy cap/rotor arm that could need changing?

Your earth straps all ok Rach?

olop_chris wrote:May just be your plugs/leads need changing, or dizzy cap/rotor arm that could need changing?

Your earth straps all ok Rach?

ummmm



My dad did say i should change the plugs..

I think I'll get the haynes manual/nextdoor neighbours dad out this xmas.

What are earthstraps?? I tried googling to no avail. Although some nice shoes did come up in images....

earth strap: there is one from the -ve on the battery, there is also one from the engine block to the car chassis. they are basically just a dirty big thick piece of cable. i used an old amp wiring kit to redo mine, but also kept the original cables too.

ecu relay and fuel pump relay next to each other in scuttle area atached to ecu

you'll want your earth straps secure or you could melt your ECU
(i've caused that)

thinking on that subject, i was going to say maybe some injector problem (not putting enough fuel in for some reason), but given what the car did following the ECU cockup (blasted the entire fuel tank into the engine thru the injector), maybe a poor strap is scrambling its signals in a subtle way and making it run badly.

or maybe its just getting old and needs tweaking. mine would sometimes splutter a bit from cold in winter, and the design is theoretically susceptible to carb icing if the inlet heater fails


then again its literally been years since i touched any of this so it could all be b*ll*cks

It really does feel like one day i'm going to be going along the motorway at 70 and she'll just cut out and not recover herself....

Well, it happened... Right on the M5, just at a fork in the motorway, right in the middle! Lol

Turned out to be the ignition coil.......if anyone was interested...

And yeah it hasn't done any of the above since I changed it, yup you heard...IIII changed it giggle.

I won't go into the whole setting the immobiser off, having lost the fob and having to get an auto electrician to bypass it for me....

at least it was a cheap(ish) fix!

good work rach, glad this thing has sorted too. it was worrying me when i was in the car that it might just conk out!

i'll keep quiet about the imobiliser too eh?

Found it!