Ongoing issues with starting

[supraguy@aol]

Did you ever check the ground wires under intake runner 5, like I asked?
PS- make sure that you wiring harness doesn't touch the EGR valve- it'll cause a short.

 

[3p141592654]

Not sure I understand exactly what you hooked up to the starter. Did you hook a ground up to the big +ve cable on the starter?

It seems like maybe there is a possibility of some damage from reverse polarity, but need more info. Often the fusible links will blow if things get hooked up wrong. You might want to do some checks to see that you have voltage going to all the right places.

 

[frontierguy25]

It sounds like you need a new wiring harness. When I bought my new harness my car has run so much better.

 

[SevenMKIII]

I haven't had any time to work on my car at all, but thought I'd bump this with a meager update.

I could not clearly hear the fuel pump coming on before when jumpered, so Aaron shipped one out yesterday. I'm going to rewire that and bypass the relay and resister for 12v constant.

I bought shielded wire and a new male/female 4-pin sealed plugs and completely rewired the CPS to the ECU. I made sure at least 15 times all the wires were going to the correct spot in my field harness. Soldered in the wires to the CPS and the needle still doesn't jump when cranking. I did test the CPS after this was done too, it is still within TSRM, high but within spec.

I wanted to ground the ignitor but one of the screws is stripped so I can't get the casing off to do so, I'll just try my best with grounding that better to the body.

I'm going to ground the coil pack to the body where it comes off of the negative terminal of the battery to make sure it is grounded well enough.

Bought a new fusible link from Toyota (100amp ALT) wtf previous owner had 10awg wire with female spades connecting it. My guess is they tried to rip it out instead of unbolt it from under the fuse box. <-- It has been like this since I have had it and I did have it running before, so I didn't think it would matter that much.

So what are my options now? I'm pretty sure all my grounds are good. Negative terminal to block. Back of head to body. Trans to body. Umm...I'm at work right now, can't think of the others but I know there are more. What all should be connected at the intake manifold? Is there a ground wire from the wiring harness?

I'm on the verge of replacing the ECU, but don't think that is the problem.

 

[3p141592654]

As I've said before, if your check engine light isn't coming on, then you need to figure out why.

A bad ECU is a possibility, especially since it seems the 100A fusible link was blown at some time, and the easiest way to do that is hook up the battery backwards.

 

[SevenMKIII]

I'm trading my scanner for an ECU with tubbie, so if we can both ship our parts out soon hopefully I'll have a working ECU by end of this week/early next week. I'm going to try to get the fuel pump in this weekend and run a better ground to the ignitor.

Everyone is starting to get mad that I still do not have it running. I do not have a car right now and it sucks. If these last resort things do not get it running I am going to take a huge loss on this car...

I just don't get why it started up and idled fine before, but I had a TPS maladjustment and somewhere in the process of fixing that it stopped running. CPS just crapped out after the first time it was running or something.

Also, will the tach needle not jump because the ECU *assuming it is bad for a moment* isn't sending an IGt signal; my CPS and wiring could be fine now that I have changed it?

 

[sneakypete]

As I've said before, if your check engine light isn't coming on, then you need to figure out why.

A bad ECU is a possibility, especially since it seems the 100A fusible link was blown at some time, and the easiest way to do that is hook up the battery backwards.

first of all you need to listen to 3p.... he must have mentioned it 5 times

second, the symptoms you described originally sounds like the cps was off a notch when you set the base timing which would cause you to not have spark. once you figure out why your cel is not coming on, you need to remove the cps and turn the crank to tdc and reinstall the cps with the notch lined up to the hole on the cps. try to start then adjust.
same thing happened to me a few months ago and i was freaking out about it and that was all it was.

 

[Poodles]

that 100amp fuse is a wire on some supras (never been able to figure out why, but I've seen enough of them like that to know it's more than likely factory)

Someone must be selling a cheap ECU somewhere in the for sale section, I'd be pulling the feilds harness out and trying to just run it normally and see if it's not something else that's fried...

 

[mk3713]

Have you narrowed the problem to spark or fuel or both. Spray some starting fluid in there see if there is a stumble or start. If there is nothing. Check to see if you are getting a 12v signal to the coil. If you are not check to see if you get any power to the igniter. Disconnect igniter turn switch on connect + led to terminal 3 refer to (tsrm ig-15) neg to ground. If there is no signal. Check voltage to ecu.PInn connector BATT and body ground ~12v. If no voltage check fuses relays fusible link. CHeck voltage from E1 and body ground should be 12v. Check voltage at computer this should tell you if it is a bad harness BAtt pin at computer 12v, +B1 12v,+B12v, Ig sw 12v. And make sure you check the grounded wires under the intake. Does your check engine light come on and turn off or does it stay on and blink.

 

[tte]

Get out a peice of paper...
Write down on it the major components and break it down into the ignition, starting, fuel system.
Work down that list and check each other off as you check.

First do a visual inspection like looking for broken, exposed wires,shorts, all fuses okay?, all connectors pluagged in, etc.

Then check the vpc setup and config settings.

Just plan it and do it in a ogranzied fashion otherwise you will waste your money guessing and replacing everything.

Cheers,
Roy