I worked on my car, now it won't start. imagine that! need help please

[tb3]

I just did the following mods on my 84 GN that I'll list below. Turns over, but won't start. I immedietly noticed fuel pump wasn't turning on, and check engine light not coming on with ignition. Which makes me think ecm or something in it just shot craps. Never had that happen before, had to be something I screwed up. Cars been down for 2 weeks, and battery was unhooked entire time. I've been careful and taking my time, by the book, and tidy with my work. My description in my sig is current except for the following mods I just did
1. Installed new poston headers, which means I had ac/alt bracket off, which is where neg. batt. bolts to ground. My neg. cable is in great shape, I sanded and cleaned all contacts and reinstalled all three ring terminal connections along with neg. cable terminal that bolts to block. (also installed new bonding strap that bolts from driver side exhaust stud to fire wall as mine was badly corroded)
2. installed new pos. cable from starter to bat. (84/85 cable from caspers electronics). my routing of the wire is good, and the 2 ring terminals on the starter block are snug and not accidently grounding on anything. The wire that goes to alt. is correctly installed.
3. Converted and installed 87 ignition module and new 87 coil pack. New ignition base adapter and wire harness adapter from caspers.
4. Installed new plug wires and AC Delco Plugs.

Every thing else electrical on the car is working. All my Fuses in fuse block are good, and I did voltage check on both sides of each fuse while installed to make sure working ok. Both my fuseable links by the starter are good also. There are 2 things I've done that may have messed me up here. 1. I powdercoated the ignition module adapter plate and the mounting bracket while I had it off ( the 2 piece bolted together plate that has 3 mounts). The Ignition module base is metal (I didn't powder coat that of course being it has electronics inside it), if its not grounded to the rest of the car will it mess up ECM? I didn't remove any powder coat on the base where it sits or to the 3 mounts where it bolts to engine. I tried temperarily grounding it with a wire just to see, but to no avail. The only other thing I did I'm not sure about was connecting the 2 orange wires that have the matching connector jacks on them that are located by the battery coming out of the wire harness from fender well. I can't remember if they where all the way connected before or not. The plugs obviously go into each other so I just figured they should be connected. I included a pic of these wires I'm talking about circled in red. I don't have updated engine pic of my car so I swiped that pic off a 84 gn on ebay. Could connecting that wire have messed with my ECM? I don't even know what its for. I went to gnttype.org and couldn't find any id. for it. Any comments or suggestions would be VERY VERY appreciated! thanks in advance!

 

[Jerryl]

Sounds like you did your homework so it must be something minor.
The orange wire is the ECM memory/power wire. This is one of the main power sources to the ECM. If this is disconnected, the fuel pump will not prime and the car will not start. While I doubt you have done any damage to the ECM or wire, verify the power to the wire.

Try the "No start test" in the sticky (see link below).
http://www.turbobuick.com/forums/showthread.php?t=33080

 

[1QUICK85]

wires in question?

There is two set of wires and 4 connectors that could plug into each other by the battery. The two wires coming out of the wiring harness should not be connected to each other. One connects to another orange wire and the other one goes to a white wire. Maybe you have them hooked up backwards?
Your oil idoit light/pressure sensor is hooked up good, wiring not loose? I know that will cause the fuel pump to not run and you said you were working in that area. Just a thought. -Nick.

 

[tb3]

I'll check it soon as I get home. I'm praying its something simple and that the ECM or anything related doesn't need to be replaced. I wanted to enjoy the car for a couple weeks, then upgrade radiator along with 160 thermostat so I can get a updated chip being the current chip is stock, may even be original.
Jerryl, if your ever up here in ol st. loo I'm going to treat you to a dinner at your restaurant of choice for all the advice you've given me since I've been member on here.

 

[tb3]

thanks Nick, I don't remember 2 sets of wires, only the 2 orange, but I'll double check when I get home, also will check oil sending light. I didn't unhook it, but i remember seeing it when I was working.

 

[tb3]

btw, I did look at the "no start test" at the top of hot air thread before I posted, but figured that was applicable for a working ECM. Way it appears so far, my ECM is totally knocked out, but, may not be the case of course.

 

[Jerryl]

....... I'm praying its something simple and that the ECM or anything related doesn't need to be replaced. .........
Jerryl, if your ever up here in ol st. loo I'm going to treat you to a dinner at your restaurant of choice for all the advice you've given me since I've been member on here.

Thanks for the kind words.
I am still paying some tuition in TR college and just returning what this great community has given to me thus far.

The OEM ECM is hard to fry so don't worry about that.


Edit;
GREAT call as well on the oil pressure connector.

 

[1QUICK85]

If you want to stay with the hot air ECM I got one with a kenne bell chip for a good price.

 

[tb3]

I may get back with you on that. I've recently bought direct scan. Which means I'll have to change out MAF (already got one), and add a air temp sensor (see guys, been doing some readin on gnttype.org). Also got a spare ECM thats been modified to hook directscan up to (got a calpak, but no 87 chip yet). But wasn't planning on hooking that all up till fall. So if your chip is cheap enough for me to justify through the better part of the year... but I don't expect you to just give it away.

 

[BRAD_PADGETT]

I have a stock 87 ecm chip which I will never use. You can have it for free. Send me a PM with your address and I will get it out to you. I agree with Jerryl that you probably disconnected the ECM by the battery-orange wire. I have done this many times this past six months. Good luck- Brad

 

[tb3]

ok, I'm back. Like a moron, I got those two wires confused. I should have labled them when I removed old pos. cable and 02 sensor. After closer inspection, noticed ones orange, and ones purple, then realised that they are same jack plug as my 02 sensor which is right there. I had the 02 plugged right into 12 volts plug off the battery , and the 2 wires from the harness plugged into each other , which would be the direct 12 volt power input for ECM, and the sensor wire for the 02.
After I corrected this, my ECM's back on line and my fuel pump cycles as normal, however, still cranks but no start. I've got plenty of fuel pressure at the fuel rail, I double checked my firing order (using original 84 firing order with the 87 coil pack). Then I set my original coil pack on top the other one (it was working OK when I removed it), hooked up the wiring harness and plug wires, and still, cranks but won't start. Could I have messed up my ECM by having the 02 sensor plugged into that 12 volt wire off the batt? Could I have messed up my ECM by having the ECM batt wire and the 02 sensor wire plugged together? I feel like a complete idiot! I guess my next step when I get home tonight is to see if I'm getting spark, then start the "no-start test" advised earlier in previous post. I'm still wondering if maybe the base of the ignition module needs to be grounded being its made of metal, I guess I'll try and ground it and see what that does

 

[Jerryl]

............. I'm still wondering if maybe the base of the ignition module needs to be grounded being its made of metal, I guess I'll try and ground it and see what that does

You are on the right track.
If there is no spark, I would review the grounding issue.

 

[tb3]

I attached a bonding jumper to the base of my ignition module yesterday, and it fired right up. What a good feeling, also nice having a nice quiet motor under the hood after cold start-up. I've had cracked headers since I bought the car. Unfortunetly I was in such a hurry that I haven't had time to go out and see how it runs with the new headers and coil pack conversion. Probably won't get a chance to drive it till this weekend. Thanks everybody for input!

 

[dragonational]

when i had my 84 i replaced my chip with a 93 octane chip. Well i had the same thing the car would crank over but wouldnt start. So i started simple fuel spark all that stuff. Everything i checked worked fine. What happened to me was one of the wires on the ECM came out just a little bit. That was my problem. Have you checked the ECM wires? Just push down on the wires not the connectors but the actual wires and see if you get the engine light. hope this helps. Harry

 

[tenright]

ummm.. doesn't the coil pack need to be grounded via the bracket that he powder coated????



T

 

[tb3]

correct. first problem was my dumb ass plugging in wires backwards. After I got ECM back on line, second problem was my ig. module not being grounded. I was actually wondering about that when I was powdercoating, its easy to just hold your finger over a spot when your shooting the powder to prevent contact when you want spot for a good ground. But since all the wires going to it are through the connector plug, didn't think it needed it. Instead of going through the trouble of removing the bracket and sanding off the powder at the three mounts, I just made a custom 3" bonding jumper and went from one of the coil pack screws over to a bolt on the manifold. It actually looks pretty decent. When I get back into town I'm going to take a pic of my engine compt. and post it since I'm so proud of it. Once again, I am really really thankful that I get replys from you guys helping me out. Some of you guys who can take these cars apart and put them back together in the dark must really roll your eyes when us newbies get on here and post with dumb questions. And with a couple of the problems I've had...I'm probably only a post or two away from something like...."How could my engine just completely disapear???......Oh wait, I'm standing at the wrong end of the car". :biggrin: