caidek

I picked up a 87 gxl and it has no spark from the leading or trailing coils. The motor turns so the starter has power. Battery voltage is 12.5. All the fuses inside looked ok. I think the 80a main in the enginebay is fried. I hear the bac clicking and I think I hear injectors but not 100% on that. I can smell some fuel so I'm guessing the pump is working properly. The pulsation dampner is dry so it must be from the injectors.

The strange thing is: There is power to clock/cluster, headlights go up and down and turn on. Radio, turn signals, antenna, logicon/blower motor works.

I'm going to bring it home tomorrow and do some more digging.

It does have a new battery. My best guess is the guy either jumped it and blew the 80 or grounded somthing on the alternator. The wiring looks to be in pretty good shape, everything is stock with emissions still on.

Anyone have any thoughts?

satch

iTrader: (1)

For the turn signals to work must mean the Main fuse is good because it supplies the voltage to the ignition switch which relays the power to the interior fuse box which relays the power to the turn signals so that particular fuse is not the issue.

There is a white two wire plug at the leading coil. Disconnect the plug and check for voltage on the Black/Yellow wire w/key to on as it should have battery voltage. This B/Y wire powers the coils so it needs to have power under the proper conditions. If it does not, then check the 40 amp EGI Inj fuse in th engine fuse box. Looking at the fuse is not a good measuring stick of its condition as a continuity test will tell one way or the other if it is good or not. Also, checking the Black/Green wire that comes out of the engine fuse box which runs to the Main relay for constant voltage (no key necessary) will tell you if the Inj fuse is good or not. If this wire at the four wire Main relay plug has constant voltage then the fuse is good to go. Also, for the pump and the Main relay to work the 15 amp engine fuse in the interior fuse box needs to be good as well. If the Main relay clicks w/key to on then that fuse is good as well.

caidek

I'm going to get the meter out in the morning and look things over. It started raining shortly after I got it home today.

I replaced the 80a fuse in the engine box while I was waiting on a tow home. The cover was off and the plastic cracked on it....After I changed it the car almost turned over. I'm leaning towards a shorted wire someplace. The tach bounces when you crank. Almost starts when it bumps near the 500mark. It keeps flooding, so i'm going to have a look at the coolant sensor above the thermostat and the AFM wiring. One thing I did notice is it looks like the upper intake ground to the firewall is not connected to the intake. Iirc that grounds many things.

The pump is definately working as I can smell the gas under the hood after a few seconds of cranking.

One strange thing I noticed. When pulling the eng inj fuse to try and deflood it if there was any spark. The tach stops functioning. But when plugged back in it works. I thought the rpm signal came from the trailing coil?

If the trailing was getting power and signal from the ecu but the leading not powered would that cause it to not start?

satch

iTrader: (1)

The INJ fuse powers the "coils" besides the injectors so the condition you created is to be expected.

The manifold ground is responsible for grounding the ECU and engine sensors. If the trailing coils fire then the ECU must be grounded though. W/key to on the engine sensors ground wire would have 0 volts as opposed to 12 volts. The car could start w/o the leading coil.

caidek

The connector for the leading coil with the b/y wire was pretty dirty. Pulled it off and check it, 5v. I pulled the inj fuse and cranked it for about on and off a few times. I think it was pretty flooded. I put it back on, topped off the coolant and it fired up. It smokes like a ******* banshee. I had to keep my foot on the gas to keep it going and had it around 3k or so. Only kept it on for about 30sec or so. I didn't want the fire dept to deal with at 9am.... One interesting thing is:

smoke was whitish, smelled heavily of gas. It was coming out around the exhaust manifold and it also back flowed out the intake.....

I pulled the fpr vacuum line and its dry....injectors stuck on all the time? Cats full of gas from sitting and it leaking the ports?

satch

iTrader: (1)

When started, a flooded engine will heavily smoke for a number of minutes before it slowly dissipates.

The B/Y wire at either coil should have 12 volts w/key to on. The G/Y wire at the leading coil would have O volts or 5 volts.

caidek

The b/y shows 12v and the g/y is 5v or 4.998 or somthin.

It smokes ALOT, like clouds for a few houses and its thick. The high humidity and little to no wind isn't helping by keeping it down low and in clouds....

I'm going to pull the leading plugs in a little bit, pull the inj fuse and let it spray out. This one has a/c and p/s so getting at the plugs is a pita.

Btw that upper intake ground thats not connected, could that cause the injectors to run always on? It seems to fire every time now, I haven't let it run more than 30 to 60 seconds because of the constant stream of thick billowing clouds of white fuel smelling smoke....

I'm thinking about taking it down to a friends shop and run it there....rather not **** off everyone on the block and have the fire dept come out to discover a car can put out that much and still run...

Btw its sat since february.

caidek

Another thought:

Would it be safe for the ecu to backprobe the injector clips with a 12v led test light while its running to see the pulses and make sure its not constant 12v to them?

We have had alot of rain in MN since the spring, maybe a combo of leaking/100% load injectors and water soaked cats/mufflers. The tailpipes are rusted off the mufflers.

I keep looking at the injectors, regulator, pulsation dampner and under the car for signs of gas. This heavy of a fuel smell and all that smoke somewhat concerns me as far as it burning to the ground out of the blue...

satch

iTrader: (1)

If you have a leaf blower then use it to disperse the exhaust smoke.

The car would not start/run w/o the main ground grounded.

You can certainly use the LED lights to tell if the injectors wires at the ECU are being sent a pulsed signal. On your car the small ECU plugs house Green wires (4 of them) that are the ground signal for the primaries and secondaries. W/the car running they shouldl flash. The front primary is Light Green (pin 3E)while the rear primary is Light Green/Black (pin 3C). Use the ECU mounting bolts at the front of this item as the ground source for the light while the LED voltage wire would go to the ECU pin.

caidek

Fixed it. The guy flooded the **** out of it, and probably had fuel vapor and lots of moisture in the cats from sitting for 6 months. After I bled the coolant I gave it some gas, ran it up to 5 to 7k a few times. It stopped smoking and the exhaust doesn't smell like fuel anymore. The gas was winter mix from february too which didn't help things to start with. It was near empty anyway so thats a good thing. After the coolant bleed it holds a perfect 750 idle and temp/oil/volt guages are where they should be at. Just need to throw some mufflers, brakes, flush and bleed fluids and maybe put some shifter bushings in and its set.

Thanks for the help

Sidenote: It's been so long since I drove a n/a, I forgot those 5th and 6th ports really do give it some kick.