Where to start?????

I"ve a 91 5.7 z28. I am about to take a sledghammer to my car!

I recently noticed that my car was running like crap. last week, I had my cruise control on and i stepped on the brake..my car wanted to go? Then I noticed when I stepped on my brake, my marker lights came on. Well, the other day, I got on the freeway and my car had no power. It felt like the timing was not advancing and it did not want to accelerate. I had my foot all the way on the pedal and it was a dog. So, i put 2 and 2 together and figure out it's probally something under the dash. I found my brake switches cracked ( I recenty dropped my steering wheel ). I removed the electrical attachemnts, then inspected them, the put them back on to try and trace which wires were the problem. Now, my dang car will not even turn over with the switches connected to the pigtails????

I am at my witts end with this car, about to put a buck a smash and have a little show outside of my house!!!!!!!!

So, where do I look for the wires that could intersect for my brakes, marker lights, cruise control, and my timing retard or ignition?

I've looked at the autozone site, but it makes little sence in regard to the swithes/attachment pigtails.

please help

 

take alook at the attachment. It may help. It is a GM service bullitin that fits your description.

 

I appriciate that bro! I'm going to check there again....

As of now, my car does not start. When I move my key to turn the car on, all that happens is the gauges bounce to the right. I was so tired last night that I did not tell the entire story. A few weeks go, I lashed my valves. One wire got pinched in the valve cover, the pink one that runs to the ingnition A few of the wires back there are so tight, it's difficult to see. So I followed the pink wire into teh cab of the car. I ended up cutting that wire and routing the wire through a hole in the fire wall because the pink wire on the back side of the hugh plug was fired. I checked each wire inside the car that was next to the pink wire. replaced 2, all contacts are good. one wire went to the blinkers, the other...i forgot. When I put my steering wheel up after replacing the pink wire inside the car, that is when I busted the two plastic switches that attach to the brakes. Man, I feel like such and idoit So, when I try to start my car, no click, gauges bump to the right, I hear my fuel pump turn on, any ideas????? PLEASE....

 

Man all I can say is get a voltometer and start tracing your problem back to wherever it starts. It sounds like it could be an ignition switch, neutral/safety switch, or starter relay. Just start at the starter and head backwards. Its really not a very complicated system, just hard to follow the wires because they run every which way. Just be paitient and thourough. Good luck.

 

Three things to check...
Check to see if the crank fuse is busted. Also check the fuse when you have the key in the start pos (this checks the ign switch). You should have 12 volts or use a light. If that is good, you should have 12 volts at the starter solenoid. Check these three things and let me know.

 

Thank you guys for helping me!

Man, I feel so lost when it comes to electric stuff. My crank fuse is intact. I get power to it as my test light turns on when I turn my key in the on position. I've not checked my starter as it's mother's day and my inlaws just showed up. Plus, my wife is not happy because I've been spending so much time and money on this POS! I would sell it, but I've got way WAY too much money into it. new engine, tranny, afr heads, supercharger, NX kit and a ford 9' in the future.

I was wondering if me routing the pink wire to the ignition switch could cause any problems? If you can bear with me, on the back side of the large plug all the wires go into from the fire wall to the inside of the car. The pink wire that goes into the ignition switch was fired on the inside side of that plug. I drilled a hole, put a rubber gromet in and routed it around the plug. that huge plug is not some sort of switch is it?

my car was running until I got under the dash and started disconnecting things to see what would cause my marker lights to not work when I pressed on the brakes. When I removed the plugs on the left hand side of the two plastic break switches, that stopped my marker lights and brakes. I am wondering if the switch is bad or if the wires are crossed somewhere. if so WHERE

Thank you guys for the help!

 

these will help...

 

Thanks for the wiring diagrams! I found thoes on autozone's site.

I forgot to add, when I did find the pink wire all burned up on the inside side fo the plug on the firewall, a green wire, blue wire (blinker) and a white and tan wire which I thinkwas for the cruise control. I"ve no idea what the green wire went to. I repaird all three wires and did not see any more damage to any of the wires. As for my starter, it's fairly new, less than 8mo old and I really doubt it's the problem. I plan on purchasing a new ignition switch tuesday. Really wierd, as soon as I turn my key and try and start my car, all gauges die. my voltage gauge drops below 8.

I"m at a loss here of what to do next. my plans are to swap the ignition switch. chase more wires and remove my dash,then go to harbor freight and by a sledge hammer

 

when you turn the key to start... does your interior light dim ? if so get your starter tested.

looking at the wiritng diagram, there is only one relay (starter enable relay )and the clutch safety switch(m/t) or the neutral safety switch(auto).
if you have a test light try probing at the relay you should have 12V on the yellow wire when you go to "start" . if you have a VOM check to see if you have a low ohm reading from the black/yellow wire to ground when the key is on. (or try to put a jumper wire from the yellow wire to the tan/white and see if it'll start, this way won't find a broken wire but you'll find a bad relay)

If this all works out then move to the switch.
check for voltage coming in on the tan/white wire when you go to "start" with the connector disconnected. if you have voltage when you turn it to start then try jumpering the switch (looks like from tan/white to purple)
if she still won't start ... check for V at the starter on the small wire.

I've never tried this but.... if you take a pushbutton switch with long wires attached and connect from the heavy wire at the starter to the small purple wire at the starter the motor should kick over when you push the button (should... I've never tried this, just something similar on an old F100 p'up )

and sorry if I have gone into WAY to much detail ... I know that after you've been chasing your tail on electrical it's easy to forget what you have and haven't checked and a fresh start somtimes helps.

just noticed this " forgot to add, when I did find the pink wire all burned up on the inside side fo the plug on the firewall, a green wire, blue wire (blinker) and a white and tan wire which I thinkwas for the cruise control. I"ve no idea what the green wire went to."
could that be the tan/white that the wiriing diagram inicates between the relay and the switch ?

Tony

 

Tony...and everyone else!!!!!!!

Thank you for the help! Tony, that helps me a lot! I"m a complete idiot when it comes to electronics. I work today (24hr shifts) and plan on following your instructions as soon as I get home, granted I dont have to take a nap Where is the ignition switch? Is that the switch that is on the upper steering column. And where is the automatic transmission N switch?

as far as the white and tan wire, I think it is for the cruise control, but I will have to look at my wiring diagram and doubble check!

As far as your statment "and sorry if I have gone into WAY to much detail", no appoligies needed! That extra detail is exactly what I needed! Like I said, I know jack when it comes to electronics

Thank you everyone, I'll keep ya posted

 

Well, so far I have power to my crank fuse, the fuse is good andI have power at my starter via test light.

Turn my key on and I try and start my engine...I get nothing at all

 

May seem dumb but my buddy had a problem with his cars electrical.....figured out he never grounded his battery wires. You have to ground the positive and negative.

So the positive cable has to have a ground for it and your negative cable has to have a ground to it.

After my buddy put grounds to his cables his car started...stayed running, lights worked again, and now everything is awesome again

So maybe your battery cables arent grounded...its a common problem when changing batteries or wires. Let us know.

 

Nope, I checked that too.

As of now, I put my test light to the yellow wire. With the key on not trying to start the engine yellow has no power via test light. When I try and start the car, yellow gets power. Pink wire closest to teh driver has power when the plug is pluged in, but it has no power when teh plug is not plugged into the switch. The brown or tan and white wire in the rear of the ignition module has power with the key on, but it looses power when I try and start the car.

What gives

 

Sounds like its not getting ENOUGH power to it? Maybe a cut in the wire?

I know nothing about electrical so Im just guessing and hoping its something you havent checked yet.

 

Well, it turns out my ingnition switch was the problem all along. I got her running and I noticed where the air tubes attach had a leak. My car was running like crap at idle and then stumbling all over the rpm range. The no 2 cylinder air tube jsut beyond the primary was cracked and spiting out exhaust. Maybe that is the reason it was running so poor upon accelleration?

Thanks for your help..now on to my header.

I just hope my acceleration problem will be solved with this fix!

 

Well, my car is still running terrible! The last time I drove it, it was not accelerating and my timing would not advance more than 20deg @ WOT. Now, my car will harldy idle??? It sounds like it's running on 4-5 cylinders. I have spark, fuel pressure is 43.5psi. Timing was set @ 6 deg advanced. I advanced the timing by ear and got little change. All cylinders are @ 185psi during a compression test. Any ideas of what can be causing my idle to be so poor?

 

Look for the ignition switch and check if it has a problem.



________________
Jerry
GM 4L80-E Transmission Controller - Get the new Transmission controller in GM Performance Parts 2006 Catalog by GM Parts Direct

 

I just replaced the ignition switch.