Need help, electric problem (I guess)

[Sebas007]

Need help about diagnosticate a problem I've since I relocate my battery.
The problem is that the engine "hesitate" when I'm trying to keep some speed, espacially if it revs higher than 4000 RPM.

Example I'm trying to keep a 70 MPH in 3rd gear...it is like the car slow down just a tiny bit and go normal and does it randomly. If I gun it...it will be fine (I think the ECU knows that it has to open it up...) samething when I left the throttle...the ECU knows that I don't ask for anyting. It does the strange thing only when I try to keep a pace. I got check engine 3 times...I reset the battery twice...the last time it appears I continue on my way and I got a problem...no more power steering, tachometer (RPM) was reading 0 RPM, , oil and battery gauge light up...I took first exit I can and and park far from the highway...I panic 5 minutes checking CP-e connections and everything I can...and I retry it (no battery disconnection nothing else then restarting it) and it work "fine". I went back home cruising on cruise control at 60 MPH (under 2000 RPM).

Things to know
- I verify and I get a 11.7 - 12.5 volts at my positive terminal
- I verify CP-e mapping and it still the same I put last time
- I even move the terminal a bit away from any sensor in the engine bay.


Questions
- What does it makes if the negative cable do not make contact properly ??
- Do you think guys that a big gauge wire (it is gauge 1 ) can produce too much magnetism field to be route near the sensor in the kick panel as the pic under show ?



What do you think it could be ??

[[SMAN]]

I found out, through some of my own testing, that the solara has a "limp home mode". I tried to put in my optima from my old car, but alas, i had left it sitting to long and it was dead dead. The battery wouldn't charge, so the car was just running off the alternator. When i would rev high, it wasn't getting enough power, and thus did some of the simptoms yours did. My guess is that you don't have a strong enough connection with your battery relocation. The ground point might not be good, or your positive might not be strong either, but most likely it's a connection issue, unless your battery is on it's way out. Running the positive wire should not create enough magnatism because your not actualy using that much power through it. It is most likely your connections. Make sure that all of them are free of pain and corrosion and are nice and tight. If you are connecting your ground via a bolt, tryputting in a spider washer (a washer with little teeth on it) around the bolt to help dig into the frame.

[Sparky5e]

From what I have seen glancing at the Electrical prints is the system uses negative switching for almost everything. If there isn't a good ground system problems can occur. One thing I mentioned in your original post was upgrading the ground system. The block, chassis and battery should have as small of electrical resistance as possible between them. Steel is a poor conductor of electricity and the systems may be fighting each other. Seems a long way from the trunk to the front using only the chassis as a conductor. If possible I would route a ground from the battery to the engine block or where the previous ground was connected.


Your Power cable may be a problem during high amp situations and improper ground. As a rule of thumb, high amp cables should stay away from control wires and cross at 90 degrees if they must meet.

[ClassySolaraGuy]

How well did you ground your battery Sebas?

[Sebas007]

How well did you ground your battery Sebas?

I used the negative cable supply in the kit (2 foot long)



I took this image BEFORE file down the paint around the hole for the negative connection but it is plug this way

[[SMAN]]

Try using one of those spider washers i was talking about. They are very cheap at a hardware store.

[Sebas007]

My Optima battery is new (less then 1 week old)
My wire are 1 AWG size (big enough for 18')

I will try the spider monkey washer. I'll also file down even better the paint around the bolt.

If there are other good suggestion, I'm open to hear them !

[ClassySolaraGuy]

I would think you would need to have a better grounding point (chassis, engine block, etc) even if its not causing your problem. Where does the stock grounding go under the engine bay?

[Sebas007]

I'm grounding in one of the frame stud. I use the bolt hole of the stock plastic tray in the rear trunk driver side.

Stock grounding area are engine block and an other place near the battery support.

[ClassySolaraGuy]

Why not ground to the stock grounding terminal? Most battery relocations I've seen have done this. I know it's a little more work but it will insure that you have sufficient grounding.

[Sebas007]

I ask electrical engineer at my job.
Told me that my ground setup is allright !

Parallel wire produce some induction, perpendicular doesn't.
To create a induction shield I could skin a 18-wire and roll it all around the positive wire, where it goes near electronics, and screw it on the engine block or whatever.

[Sebas007]

Not seem to be that...I didn't make the shield yet but I put some distance between where the wire was passing (in the engine bay and under the steering wheel) and I still feel this stupid hesitation !!!!!!

[Sparky5e]

Formerly being an electrician I can tell you poor grounds have caused more ghost problems then you could ever imagine. Remember the Toyota's use negative switching and you are losing allot of resistance in the chassis. I know it isn't the answer you are looking for after the time you spent doing a great looking job, but i truly feel that is the problem especially since you pulled the cable away from the wiring harness.

[ClassySolaraGuy]

Sebas,

I know you may not want to hear this but just to be sure about the grounding try the following:

-Disconnect your new positive wire that's bolted on to your stock positive
-Reconnect your stock negative terminal under the hood
-Connect your battery up back under the hood

See if you still have the problem. It should take more than 10mins or so to test it out. GL!

[Sebas007]

Sebas,

I know you may not want to hear this but just to be sure about the grounding try the following:

-Disconnect your new positive wire that's bolted on to your stock positive
-Reconnect your stock negative terminal under the hood
-Connect your battery up back under the hood

See if you still have the problem. It should take more than 10mins or so to test it out. GL!

I wanted to revert stock since monday but I losted the bolts (man...wtf !! )
But, this morning, I find them out of a box containing my stock intake system.

By the way thanks Sparky5e for your electrician feed back...are you meaning that the whole frame is not a good place to put the ground wire ?? Else where I could put it ?? I saw a lot of ground wire in the engine bay on the frame and also inside near the left foot driver side.
I also don't know where the throttle-by-wire (why using this kind of name to specify an electronic throttle ??) is located but I think it is located near the throttle pedal inside the car and my wire go near this point...I really have to put the shield...but first I will go back to stock to see if everything is back to normal and eliminate the most hypothesis as possible !!