popped fuse, major eletrical problem

[Smally514]

popped fuse, major eletrical problem

hey people REALLY need help on this one.

so I have a 1996 GTS-T R33 series 2

 put my car in to have some work done as follows.

ECU,Injectors,boost controller and boost gauge.

all very standard things to upgrade.

it was on the dyno, didn't even get to any major pulls for power, just started to get the car running on the base tune.

out of nowhere car decides to shut down. ok popped fuse replace it now car won't start.... 

my auto elec ripped the whole car apart tested everything relays, looms more fuses, fuel pump etc.

follows the short to the dash cluster just as he starts taking the dash out, short vanishes???

 been four days and still can not locate problem. head mechanic said this has been a head F%#@ has never come across this problem before..

just wondering if anyone has had similar problems or if anyone can think of what if could be cause it just doesn't make sense. 

any information would be appreciated cheers.

 

[Scott Black]

If the shorts.gone will the car start now and

[Scott Black]

Also any wires running close the a bit of sharp metal or plastic behind the dash that they may have cut threw and exposed the wire,
Has he tested all critical stuff for the car to not run, eg fuel pump powering up, fuel pressure at the rail, power to the ecu,power to coils, power to injectors injector pulse,coils firing, cas signal scopes at ecu and at cas
Finally what fuse was it blowing as that might give.more insite into the problem.

[Smally514]

I spoke to him yesterday and to the best of my knowledge he has tested literally everything he could think of from major components to something as little as the wiring in my aftermarket head deck, Including all work he has carried out. However he did not tell me which fuse had blown.. car still won't start which is why they are so baffled at what's going wrong.

That's why my guess was an exposed wire of some sort within the dash cluster. But apart from that they don't really have much else to go off. He told me that he has never come across this kind of thing before with such simple upgrades.

[Scott Black]

Just because upgrades where done doesn't mean there the cause of the problem yet always good to check over them
The reason it's important what fuse blew. Say it's an ecu fuse and it had the wrong rating in it, it may have damaged the ecu itself before blowing or what other circuits it's on
Yet as for the car not running, I think it's he's lost he needs to take a step back and pretend it's a car that's just come in not running.
First go over the basics
Does it have fuel
Does it have fuel pressure
Does it have compression
Are the plugs in good Condition and not fouled.
Removing timing case upper cover and ensure cam timing still correct
Get an ecu pinout and ensure ecu has power and earth everywhere it should. Including when cranking the motor
Check power to critical circuits,cas injectors and coils and afm, check injectors pulse and coils fire
Check your getting a good signal from the cas,
Check ecu data to ensure it knows the engine is cranking and the afm signals are reasonable

Check each one of them individually as if the car doesn't run it will show up as a problem there.
When you work out where the problem is then you can work out how to fix it.

I'm a mechanic and auto elec by trade and the amount of time I've wasted by skipping something small that I thought couldn't be a problem only to have it stuff me over later is ridiculous, that's why sometimes you need to take a step back from the issue and start over.
Old saying is can't see the forest for the trees.

[Scott Black]

[Smally514]

Yea that's all very good points I'll give him a ring and put in some pointers without sounding rude and as if I'm telling him to do his job haha. Appreciate your input mate I'll post up on here again when I find out what the problem was and if what you said helped point it out.

[Smally514]

got my car back today.... turns out that problem was o2 sensor and what long story short it fried the o2 circuit in my ECU!! of all things. so now thats all fixed. my car is surging on fuel and I can't turn a corner any faster than 20KM/H without the car cutting out then as soon as I get back into a straight line give it 2 seconds BAMB car turns into a skyline again?? any thoughts?

Edited December 1, 2016 by Smally514

[Trex]

Take it back to the workshop, tom. They shouldn't have given the car back to you like that.

[Smally514]

oh yea and did I mention that it broke down literally 15 minutes after picking it up was stuck on centre lane at traffic lights for about 10 minutes and car wouldn't start hahahah talk about buying a Lemmon I hit the jackpot :D. 

 

yea I'm putting it back in on Monday.. annoying thing is it wasn't doing any of this when they test drove it, all of a sudden the owner gets the car back and bamb more problems more money. I am thinking its time for surge tank also.

[Trex]

Haha you haven't had the best run with that car. Time for a stagea  

I haven't heard of 33's needing a surge tank. You would have gotten a new fuel pump at the time of getting the other gear, so the sock may need aligning? or a possible random voltage drop? or they've f**ked the wiring while trying to wire in the link... Can't see an o2 failing and taking out the ecu like that. That's just odd.

 

 

[Smally514]

oh yea and did I mention that it broke down literally 15 minutes after picking it up was stuck on centre lane at traffic lights for about 10 minutes and car wouldn't start hahahah talk about buying a Lemmon I hit the jackpot :D. 

 

yea I'm putting it back in on Monday.. annoying thing is it wasn't doing any of this when they test drove it, all of a sudden the owner gets the car back and bamb more problems more money. I am thinking its time for surge tank also.

[Smally514]

WOW just a small update. Problems nearly over corner cutting problem was none other then a tricky fuel pump relay replaced it and it's pearling. Now I just need to sort out a small over boosting issue. Apart from that my car is a little weapon now. Am very happy