Daewoo Cielo 1997 SOHC Fuel pump ECM fuse keeps blowing

N/A tech, Cold Air Intakes, Spark Plugs/wires, Cat backs, Exhaust...etc

Moderators: daewoomofo, Moderators Group

Locked
rogerwilco
Posts: 3
Joined: Sun Aug 14, 2011 8:27 am

Daewoo Cielo 1997 SOHC Fuel pump ECM fuse keeps blowing

Post by rogerwilco »

The 30 amp fuse on the fuel pump - ECM circut on my 1997 Daewoo Cielo 1997 SOHC keeps blowing. I have effectively ruled out the pump, and the wiring loom to the pump as being the problem, as I have wired the pump totally seperate from this circuit. However,when I turn the key on, the 30AMP fuel pump - ECM circut fuse keeps blowing, even when the pump is not electrically connected. It has been intermittent, sometimes the fuse does not blow and i can drive for 10 minutes, then it'll blow for no apparent reason. Currently it is blowing every time the ignition is switched on. I have determined that when the fuse blows, it must effectively be stopping the fuel injectors from operating, because I know that fuel being is being supplied to them by the pump (since I now have on a totally different wiring circuit and know that it is working). Possibly the ECM? any ideas? From previous post to this forum and a google of the 'net, this looks like it is not a new problem but not definitive answers have risen to give a clear answer to the issue.
Would be a nice one to get sorted folks, hope you can assist.
Daniel
Expert
Posts: 1298
Joined: Mon May 03, 2004 8:28 am
Location: Belgium

Re: Daewoo Cielo 1997 SOHC Fuel pump ECM fuse keeps blowing

Post by Daniel »

On the cielo there could be a specific oil pressure switch (item S4 with 3 prongs) which can by-pass the fuel relay when oil pressure is achieved. It my be defective by grounding +12V. Remove the oil pressure connector and look if problem persists. When car is stationary you may use a test-lamp (headlight bulb 12V/50W in this case) in place of the 30A fuse so you see when the problem occurs. This spare you fuses too. ;) .

Hope it helps,
fuel pump.JPG
rogerwilco
Posts: 3
Joined: Sun Aug 14, 2011 8:27 am

Re: Daewoo Cielo 1997 SOHC Fuel pump ECM fuse keeps blowing

Post by rogerwilco »

Thankyou Daniel
Problem seems to have been with the connections going into and out of, the ECM. By wiggling these several times, the problem stopped. Possibly corrossion etc in there, the wires are quite densely packed. Incidently, an inspection of the whole car wiring loom showed where the wires continued from the fuel guage sender and onto the fuel pump under the car, that there were signs of abrasion where the outside of the fuel tank jams these wires against the chassis. This is likely to cause a short in time, and is a design fault that is no doubt causing problems with this model car. In my instance, I'd ruled out this possibility as I'd bypassed these wires with new ones on the inside of the vehicle.
MMamdouh
Moderator
Posts: 7299
Joined: Wed Feb 18, 2004 8:33 am
Location: Cairo, Egypt
Contact:

Re: Daewoo Cielo 1997 SOHC Fuel pump ECM fuse keeps blowing

Post by MMamdouh »

this was an issue with some cars here... turned out to be an electrical wire going under the plastic trim found under the right hand side door and the wire's isolator got damaged due to (foot kicking) of passengers around this area

check the wires going through this area (under the plastic trim) and check for damages

MMamdouh
Driving is the utmost fun you can have with your pants on!
Check out my ride: http://www.cardomain.com/ride/567267
Image
rogerwilco
Posts: 3
Joined: Sun Aug 14, 2011 8:27 am

Re: Daewoo Cielo 1997 SOHC Fuel pump ECM fuse keeps blowing

Post by rogerwilco »

Daniel wrote:On the cielo there could be a specific oil pressure switch (item S4 with 3 prongs) which can by-pass the fuel relay when oil pressure is achieved. It my be defective by grounding +12V. Remove the oil pressure connector and look if problem persists. When car is stationary you may use a test-lamp (headlight bulb 12V/50W in this case) in place of the 30A fuse so you see when the problem occurs. This spare you fuses too. ;) .

Hope it helps,
fuel pump.JPG
Daniel
It appears you are indeed an expert!
Several months down the track, the problem of the blowing fuses in the fuel pump circuit reared its ugly head again.
The short version of the story is that the oil pressure switch / sender was faulty. Replaced it, problem gone! Magic!!
I believe my previous post regarding the 'wiggling' of the wires into the computer box 'fixing' the problem was wrong, and that the 'fix' was purely a coincidental reprieve.
A lack of dashboard oil light ( after some intermittant false low pressure light alerts) finally steered me to the possibility that the oil pressure switch was in fact the problem. i wish I followed your advise in the firts place! I pulled the oil pressure switch/ sender apart after removal and it was a stinking, burnt-out mess inside.
Makes you wonder though, why such a crazy electrical circuit was ever designed. Far from intuitive to trouble shoot.
If I had more money and the engine of this car wasn't in such good nick, I would have got rid of this car long ago.
many thanks for your expert input Daniel
best
rogerwilco
Daniel
Expert
Posts: 1298
Joined: Mon May 03, 2004 8:28 am
Location: Belgium

Re: Daewoo Cielo 1997 SOHC Fuel pump ECM fuse keeps blowing

Post by Daniel »

Glad it is fixed. And thanks for reporting results.
BTW every member here is a expert. That's what makes this forum the best one for Daewoos.
benzino
Expert
Posts: 1530
Joined: Sun Mar 09, 2008 4:14 am
Location: Snowy Mountains, Australia

Re: Daewoo Cielo 1997 SOHC Fuel pump ECM fuse keeps blowing

Post by benzino »

one of the best for any make of car full stop
~2.0L Lanos~EHPAS~H&R Springs~KYB/GTS Shocks~
Image
Locked