Tell me why it won't spark!

[the1andonly0032]

Old Problem:Bad Battery

Jumped it but then blew ALT fuse so I got a new one of those and a new battery

New Problem: No spark
It turns over but then just cranks and cranks and I pulled the spark plug out and put it on some metal and no arc what else could have gone bad in this electical system between the battery jumping and the sparkplugs

Anybody? please take 5 min. no one answered my last post

 

[nissota]

Old Problem:Bad Battery

Jumped it but then blew ALT fuse so I got a new one of those and a new battery

New Problem: No spark
It turns over but then just cranks and cranks and I pulled the spark plug out and put it on some metal and no arc what else could have gone bad in this electical system between the battery jumping and the sparkplugs

Anybody? please take 5 min. no one answered my last post

Did you check the EFI fuse?

 

[Dirgle]

Did you check the EFI fuse?

Yep first option is to check all the fuses.

 

[Supraflymk3]

Old Problem:Bad Battery

Jumped it but then blew ALT fuse so I got a new one of those and a new battery

New Problem: No spark
It turns over but then just cranks and cranks and I pulled the spark plug out and put it on some metal and no arc what else could have gone bad in this electical system between the battery jumping and the sparkplugs

Anybody? please take 5 min. no one answered my last post

test your igniter and make sure thats good and if its not i have one i'd be willing to sell you.

 

[Nick M]

IGN fuse under the driver dash kick panel. Dont trust a visual check on fuses.

 

[bigaaron]

Old Problem:Bad Battery

Jumped it but then blew ALT fuse so I got a new one of those and a new battery

New Problem: No spark
It turns over but then just cranks and cranks and I pulled the spark plug out and put it on some metal and no arc what else could have gone bad in this electical system between the battery jumping and the sparkplugs

Anybody? please take 5 min. no one answered my last post

Were the jumper cables possibly hooked up backwards for a sec?

 

[the1andonly0032]

EFI is good IGN fuse was bad so i replaced it and as soon as i turned the key it blew it out again so that has it narrowed down to my IGN wires and I found out my brother tried to jump my car without me and DID hook them up backwards so yes all these problems are because of that so what fuses relays or wires do you guys think are screwed over if its blowing the IGN fuse and still not sparking

 

[bigaaron]

EFI is good IGN fuse was bad so i replaced it and as soon as i turned the key it blew it out again so that has it narrowed down to my IGN wires and I found out my brother tried to jump my car without me and DID hook them up backwards so yes all these problems are because of that so what fuses relays or wires do you guys think are screwed over if its blowing the IGN fuse and still not sparking

Oh no, that is bad
Basically anything that polarity sensitive could be fried, but I will cross my fingers for you.
Main alternator fuse blew so alternator could be bad. Diodes in alternator don't like 100 amp+ reverse polarity spikes!
ECU could be bad

Also (you probably already know this) only replace the fuse with the same amp rating, do not go higher then the fuse rating for that spot. I have seen people try bigger fuses thinking the fuse was the problem :nono: but then things start to burn!

I wish you were local because I would bust out the Fluke meter and having it running in no time but to diagnose the problem over the internet is gonna be tough.

I hope your brother learns his (possibly expensive) lesson!

 

[bigboost7m]

Did you check the resistance in the coil pack?

 

[the1andonly0032]

I said EFI is good it never blew I did a resistance test on it and it had none how would i go about checking the resistance in the coil pack?

 

[bigaaron]

I said EFI is good it never blew I did a resistance test on it and it had none how would i go about checking the resistance in the coil pack?

Coil pack is powered from 30a am2 fuse in engine bay, is that the fuse that blew?

 

[the1andonly0032]

I checked all fuses in the engine fuse compartment and they are all good now the ALT was the only one that blew then i checked a few in the drivers kick panel and all were good except for IGN which blows everytime i try to turn it over....by the way why arent I getting a check engine light when it wont turn over? and can i do a diagnostic without a check engine light?

 

[bigaaron]

ecu is possibly dead

 

[supra90turbo]

yes you can do a diag check without a CEL.
http://supras.com/06/techcenter/display.php?QID=4

 

[bigaaron]

yes you can do a diag check without a CEL.
http://supras.com/06/techcenter/display.php?QID=4

But not with no ecu function.

 

[boost fiend]

sounds to me like ya JUST MIGHT have yourself a dead ecu there fella.

i dont like to be the bringer of bad news. i have yet ot find a way to test a ecu yet. hit up your local junkyards. try to find a diffrent ecu.

i could just be wrong and it could just be bad wiring or a dead alt since your bro might have hooked it up wrong. take the alt off and head to your local vatozone and have it tested.

if the alt is ok, i myself would start testing eveything short of the ecu and see if its bad yet. if it is bad replace it. look up all the tech stuff at the online tsrm. if everything is ok, then......well................

 

[Nick M]

Before you going buying an ECU for a fuse that blows, make sure you understand why a fuse blows. The current in the circuit is higher than the fuse rating. This is to protect the device in the circuit, which draws less than the fuse.

If you blow the IGN fuse, you have a direct ground somewhere. Take a look at the TSRM wiring section to find what device is powered through that circuit. Like an ignition switch.

 

[bigaaron]

Before you going buying an ECU for a fuse that blows, make sure you understand why a fuse blows.

There is an IGN fuse 7.5a for the alternator and airbag system power. Like I mentioned earlier, the alternator probably took a big hit from reverse voltage. Unplug the black connector on the back of the alternator and see if it is still shorted. There is a ECU-IG fuse 15a that is for everything from abs to pps, cruise, integration relay, etc...

 

[IHI-RHC7]

Hmmm. Looks to me like IGN powers the ECU.
ouch.. It looks to power ONLY the ecu and charge light.

Here's the charge light diagram, it goes straight back to the alt. Unplug the alt and try to crank it with a new fuse, if it still blows then there is a way to test the ecu.

Let us know if unplugging the alt fixes it.
-Jake

 

[the1andonly0032]

ok sorry it took so long i went to las vegas for the past week but i just tried to unplug the alt and tried a new fuse and it did the same as before....blew 7.5 amp IGN fuse as soon as i try to turn it over and then the spark plug wont spark after that fuse blows....im thinking a power wire is grounded somewhere in the IGN fuse circut so what wires are in that circut that i could check for a ground and what other clever tricks could i try