??? Short To Ground ???

[Dr Chill]

Last night I took the my supra on its 1st long distance voyage ....
I did make it to my destanation ... On the way home , I was about 1/3 the way home, and my EFI fuse popped .
When I put another fuse in its place IT blows , Instantly .
I will be studying MY TSRM tomorrow , But if any of you guys have had similar issues , Please give me some insight . I am no sloutch when it comes to figureing out my issues .

Do ya'll think Its a short to ground ?

Just thought I would let my fellow supra Brothers & Sisters how my day went also ...
I still love my supra , But today she let me down :3d_frown:

PS ... I will use search feature as well .

 

[jetjock]

Shorts usually cause that kind of thing alright

Check your O2 sensor wiring. Melting against the exhaust manifold is somewhat common and will cause this. So does chaffed wiring at the rear of the intake manifold. If it blows with the key off it's not going to be the O2 sensor wiring though. It's either gonna be a short to ground in the engine harness on the right side or a toasted ECU...

 

[Dr Chill]

Shorts usually cause that kind of thing alright

Check your O2 sensor wiring. Melting against the exhaust manifold is somewhat common and will cause this. So does chaffed wiring at the rear of the intake manifold. If it blows with the key off it's not going to be the O2 sensor wiring though. It's either gonna be a short to ground in the engine harness on the right side or a toasted ECU...

Thanks , I dont have a spare ECU ...
Tomorrow , when the sun comes out I will be up checking all the things you posted , I hope its not the ecu But its probable that it is .
I have a super moniter & when I tried to use it to check for any codes , It never pulled any
it looked like this :
ENGING--
ECT--
A.B.S.--
basicly , pulling no codes .
Thanks again , Jetjock for the insight

 

[jetjock]

Actually it's probable it isn't, just that blowing with the key off narrows it down quite a bit. If it only blows with the key on it could be lots of things. Bad VSVs, idle speed control valve, even a problem with the fuel pump. Disconnect one thing at a time until it holds or put a light bulb in place of the fuse until you find it...

 

[Dr Chill]

Actually it's probable it isn't, just that blowing with the key off narrows it down quite a bit. If it only blows with the key on it could be lots of things. Bad VSVs, idle speed control valve, even a problem with the fuel pump. Disconnect one thing at a time until it holds or put a light bulb in place of the fuse until you find it...

So use the bulb till it shuts off ?
I did run a bulb off of it earlier while trying to fix it on the side of the road ...
It was pretty dark , so I didnt get the best view of most of the wiring .
Yes , I have tools at all times , Even electrical . lol .
every supra owner should keep the essentials with them ... always , no exceptions , I am glad I had mine tonight , Just wish I had a bright ass light . :sarcasm:

 

[jetjock]

The bulb will go from full bright to dimmer when the short is cleared. That way you won't burn though fuses while trying to find it. And yeah, every car should have certain things on board at all times. A good flashlight and fire extinguisher paramount among them. Amazingly (to me at least) the majority of people I meet carry neither...

 

[Dr Chill]

Jet jock...
I was going through a ton of related threads last night/ morning & I noticed that My issue seems to be a common issue among the supra.
I also noticed you have a lot of effort in helping the supra community with theese issues & Im sure others .... What Im getting at is :
You have much love for the supra , & the supra community .
Thanks again for the help . I would be out there messin with it , But its raining today in south mississippi.

 

[ForcedTorque]

Don't you realize how much faster your car could be WITHOUT that toolbox? I mean you may have even gotten home for tools before there was a problem. LOL

We've had the same pissy ass rain across the state line. I was gonna try to get my boost gauge wired up.

If JJ can't help you, you either have a serious problem with your car/communication/brain.

 

[Dr Chill]

Don't you realize how much faster your car could be WITHOUT that toolbox? I mean you may have even gotten home for tools before there was a problem. LOL

We've had the same pissy ass rain across the state line. I was gonna try to get my boost gauge wired up.

If JJ can't help you, you either have a serious problem with your car/communication/brain.

he mentioned something about that , but ruled it out by the symptoms
But ya never know :sarcasm:


I will just have to hook up my boost controller to make up for the weight of the tools

 

[Dr Chill]

Ok ,
so I got the EFI fuse to quit blowing ,
Now Im getting no fuel pressure ...
So Im gonna take a guess at fuel pressure relay ....
I jumped the pump over & could hear the pump kicking on , So I am 9O% sure the pump works , I still have much work to do .

 

[ForcedTorque]

You could try doing the 12V fuel mod on it. That would bypass the old wiring to the pump. I did a write up on it with pictures in the tech section.

 

[Dr Chill]

You could try doing the 12V fuel mod on it. That would bypass the old wiring to the pump. I did a write up on it with pictures in the tech section.

Cool, I will have to have a look at the write up sometime tonight .
Thanks
John B

 

[Dr Chill]

Today I had some time to work on the Supras NO STARTING issues .
I am getting fuel ...Pulled plugs to verify .
I reset the timing as the TSRM says .... By the Book ...
It seems ,When I turn the engine over to crank , It wants to, ... But never does .
I checked the super moniter for codes ......
I have a code 12
I also have a Code 24
1 is intake temp , The other is afm
If anyone has any Ideas , please feel free to give me some advice .
I search threads & use the tsrm & still no start .
Thanks

 

[easternguy2005]

How did you fix the short and the fuel pump relay ?

When you say "it wants to" does that mean it actually kicks a bit ?

 

[Dr Chill]

Well Ive came to the conclusion , That MY issue may be my CPS , The wireing was all jacked up & frail .
I had a look inside & noticed some tiny cracking on the 2 Square black things ,,,, Im no electriction ...But can figure sh!t out ...
I Kept looseing spark , ....
My buddy is gonna try a rewire on the inside of the CPS , But it dosent look too promising .

Eastern guy 2OO5 ....
How did you fix the short and the fuel pump relay ?

When you say "it wants to" does that mean it actually kicks a bit ?

I found some bad wires on the O2 sensor , I fixed them . Also had some very frail wireing on the green CPS plug , So I hard wired them together , I have a new plug from the JY I will be useing in order to fix the wireing...

& Yes ... It would sputter a bit , Then I would lose my spark to the plugs .
I even reset the timing today , Just to be sure . Still the same .
Its been a long day diagnoseing the Supra .
Maybe tomorrow

 

[Dr Chill]

So I just chilled the next day , But had a buddy come take a look at the supra with Me , As its kinda hard to crank the car & look under the hood @ the same time .....

Has anyone here on SM have problems with their COIL PACKS ?
My buddy seems to belive it may be 1 of my coil packs ...As it has a weird spark pulse ...
the middle pack & the one to the left of it seem to spark fine , But the one on the right hand side has a crazy fast off pulse spark .... Thats the best way I can describe whats up with the SUP'

I get fuel for sure , I just lose my spark ....
I also checked for codes , & pulled a code 12 & a code 24
So .... tomorrow , I re-wire My CPS , & try another Coilpack .....
Wish Me Luck .....

 

[easternguy2005]

Here's to hoping its the coil pack. Do a ohm meter check on it to see if that test in the TSRM.

I remember the ground wire being my problem and dropped new plugs and new dealer wires in and never visited that problem again.

 

[Dr Chill]

Here's to hoping its the coil pack. Do a ohm meter check on it to see if that test in the TSRM.

I remember the ground wire being my problem and dropped new plugs and new dealer wires in and never visited that problem again.

I will for sure give that a try tomorrow ,
How much are the wires from the dealer ... I heard you can buy a set for a V8 tundra & they are real close to the supra wires

 

[sneakypete]

tell your buddy to rewire the connector for the CPS while he is at it. often time that is the problem. sounds like your harness isnt in good shape. you may want to consider repairing/replacing to spare yourself from future headaches.
-pete

 

[dumbo]

it sounds as if the cps is probable, have you check it per tsrm, and coils and igniter. i would focus on that, but not exclude everything else. i would ground the bracket of your coil pack, and install the internal ground of your igniter for good measure. even if one of the coil packs has a open and was not working i'd say i tihnk it would still run on 4 cylinders, not pretty though. i wouldn't get wires from the dealer, nor a tundra. why not order ones for your car from napa or something, got my msd's from ebay-perfect fit.

EDIT: just read the first page. how did you get the EFI to top blowing?