I have recently put a new rear subframe on my mpi cooper w reg. Obviously ive had the tank out and had the pump and sender wires disconnected, the car was off the road for a month with out the battery one or the engine started during that time, (as other welding work was carried out under the boot floor and heel board)
3 Days ago I started the car for the first time and it ran fine for a day no problems, the next day I went to put some fuel in and 100 yards up the road from the garage the engine cut out and would not restart. My first thoughts were 'ohh crap I bet ive put diesel in!' but i had not. What had actually happened on closer inspection was the fuel pump fuse had blown and id made the 100 yards up the road on what was left in the fuel lines. I replaced the fuse and was on my way.
Last night I was driving to my local mini club meet and the same thing happened again! So I put another spare 10amp fuse (which is what its supposed to have) but this time it blow the fuse soon as I turned the key.
I went through 3 fuses before the engine actually started and ran continuously, so oen the way hoem from the meet I put a 15 amp in.
During the time of changing the subframe, I was doing it down at a scrapyard thats owned by a member of my family, in the garage there over the inspection pit, but next door to the scrapyard is a mechanics garage and one of the mechanics had been giving me a hand with the welding.
Now when he was cutting out the rust on the heel board he accidently went through the wiring loom with the grinder, it cut 3 wires, which he soldered back together and put heat shrink covering on them seperatley. So obvously our first thoughts are, if the solder has been sharp and pierced the heat shrink it might be shorting out on another wire, but on inspection this is not the case and the soldering is all fine.
I have had to revert to oputting a 15amp fuse in the fuel pump slot and this hasnt been blowing, but the car has been cutting out and not wanting to start back up again, the fuel pump is just not working, then it will jsut randomly start and drive fine but the randomly cut out again and the 15 amp fuel isnt blowing, so I tried a 10amp in and for a few times that didnt blow but the car still cut out, then on occastion it does blow the 10. So then our thoughts turned to the pump itself and maybe it is on its way out and drawing alot of current, but why does it cut out and only blow the fues now and again?
Then later today when I was going over to see the mechanic again it cut out on a back road (as I had been avoiding the main roads) i had the 15 amp in but it didnt blow, but while the car was switched off just after it cut I heard what sounded like a relay clicking on and off very quickly, so I popped the bonnet to find the clicking noise was comming from a unit that sits just in front of the fuel reset switch on the passenger side near the bulkhead, it has a 2 wired connector going into it and what looks like one of the fuel lines, I put my hand on it and could feel that it was this where the clicking was comming from, so Im guessing theres a relay in there?
I put the bonnet down got back in the car and tried to start it again, it started first time and hasnt cut out since the unit started clicking (which the clicking went of after I restarted the car) its nto donem it since and i have put the 10 amp fuse back in and it hasnt blown since either, but I wondering what this is been caused by? Also at the time the car was cutting out the engine seemed to be not runnign like it usually does abit noise on tick over little rattly and lumpy, but now its fine?
Could it be something that has sorted its self out or the start of some sort of fuel/electrical system problem?
Sorry its long winded but I wanted to get all the facts down.
Thanks,
Jake
P.S dont ever buy a fuel cut off switch... just pull the fuse out! haha
Edited by Jake Didsbury, 06 February 2012 - 08:19 PM.
