Engine One Side Hot, One Side Cold, Runs Like Crap
Safety Car
Joined: Dec 2007
Posts: 3,616
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From: Sandhills of North Carolina
I tell you what...........I admire your diligence. I have no idea what I would have done if that had been my car. Hang in there! You got the best right here on CF to get it squared away! 
Thread Starter
Pro
Joined: Nov 2009
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From: Maple Grove Minnesota
Thanks Weav’s Vette, I agree 100%
The blue wires are connected to the ECM as follows.
24 pin connector
A12 - black/white
A11 - black/pink
A10 – brown
B3 - black/red
32 pin connector
D1 - black/white
D2 - black
D3 - black/white
D10 – black/white
The blue wires are connected to the ECM as follows.
24 pin connector
A12 - black/white
A11 - black/pink
A10 – brown
B3 - black/red
32 pin connector
D1 - black/white
D2 - black
D3 - black/white
D10 – black/white
Thread Starter
Pro
Joined: Nov 2009
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From: Maple Grove Minnesota
Out of curiosity I put all the blue wires back the way they were spliced into the ECM harnesses and tried to start the car using the new Vats ignition cylinder hooked up and it started.
Still hard to start, hesitates when you put the throttle to it and get an occasional pop apparently through the TB but it’s running on all eight cylinders. What a difference!
But why does it run with all the blues wires hooked to the ECM when there all twisted together? And not with them disconnected?
Still hard to start, hesitates when you put the throttle to it and get an occasional pop apparently through the TB but it’s running on all eight cylinders. What a difference!
But why does it run with all the blues wires hooked to the ECM when there all twisted together? And not with them disconnected?
Team Owner
Joined: Jan 2003
Posts: 20,324
Likes: 250
From: Summerland B.C. Canada
The blue wires are tied into system grounds. Sounds like the PO had an ECM ground problem and tied all the system grounds together. Look to see how many ground wires/straps are attached to block, just above the oil filter. You may see some that are not connected.
Thread Starter
Pro
Joined: Nov 2009
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From: Maple Grove Minnesota
I reset the idle, TPS and timing and she’s running great. 
Took her out for the first time sense I got her and it was a gas! 
Didn’t know what I was missing.
Still have a lot of work to do with the wiring but it’ll be worth the effort.
Took her out for the first time sense I got her and it was a gas! Didn’t know what I was missing.Still have a lot of work to do with the wiring but it’ll be worth the effort.
Burning Brakes
Joined: Oct 2009
Posts: 773
Likes: 2
From: Minneapolis MN
Finish getting all that wiring fixed & you will be so relieved.Then get that carpet shampooed,those new seats in,maybe some new floor mats,maybe a dash mat & your done with interior.Get those fluids changed-brake,power steering,grease suspension components,oil change etc.I will help you if you need it.I don't mind helping for free but I would've charged for that wiring nightmare that you are tackling by yourself & doing a great job.Does the factory alarm work?How does it drive?Those l98s are torquey.Any noises on the test drive?I'll swing out there one of these days & have you take me for a ride & help you if you need it.In the mean time I'm doing side jobs trying to get the bills paid.I worked on a crappy 1985 Jag XJ6 today
Get some miles on those nice tires
Thread Starter
Pro
Joined: Nov 2009
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From: Maple Grove Minnesota
Well its back to running on four cylinders again. Sure was fun while it lasted!
I checked the injectors and have 17 ohms on each and 12 volts on the connectors. Should there be 12 V on each side of the connector? I have 12 V on both sides.
I checked the injectors and have 17 ohms on each and 12 volts on the connectors. Should there be 12 V on each side of the connector? I have 12 V on both sides.
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Thread Starter
Pro
Joined: Nov 2009
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From: Maple Grove Minnesota
Just went out and pulled the connectors off the ECM. Checked the voltage (ignition on) and probed D15 with pos and D1 with neg and have 11.23 volts did the same with D16 and got the same voltage. ECM BAD? or is it still a grounding issue?
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
Hopefully the injector harness doesn't have an intermittent wiring issue...it is best to remove the loom (off the affected side/bank of the harness) and visually inspect then ohm each grounding pin of each injector clip back to the ECM connection end of the harness. This is quicker and easier than you'd think.
At this point it sounds like the 12 volts is making it all the way through to the ECM....so that's a good thing. Ohm the ground pins of the ECM harness back to a the battery or "solid" ground on the frame to ensure all is well.
After all these checks I'd hook everything back up including the old ECM and see if the same problem exists.
If your good on the voltage/resistance readings and the same "dead injector bank" problem still exists then it sounds like it may be time for a replacement ECM.
Team Owner
Joined: Jan 2003
Posts: 20,324
Likes: 250
From: Summerland B.C. Canada
A12,D3 and D10 are spliced together down the line and are grounded to block, above oil filter(black wire).
D1 is another ground wire heading to the same grounding point on block(black/white wire).
Test those for continuity to ground. You may find one or both of those ground circuits are not making it to block.
A11, B3 and D2 grounds should be supplied by ECM and not a jumper to ground.
Also A10 should not be jumpered to ground.
Fix that, then move forward.
Is one side cold again ?
The ECM sends the same ground path to both banks of injectors. If one side is not getting ground to fire injectors, you may have a bad connection at D15 or D16 or an open between ECM and the injector harness of that bank.
Thread Starter
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From: Maple Grove Minnesota
Thanks 86, I’ll double check the grounds you mentioned first chance I get. No garage so I’m working on it outside and we are under a Tornado watch right now and it doesn’t look good outside.
Didn’t check to see if one side was still hot I can tell the bank is out again by the way it runs but I’ll check that too.
Didn’t check to see if one side was still hot I can tell the bank is out again by the way it runs but I’ll check that too.
Thread Starter
Pro
Joined: Nov 2009
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From: Maple Grove Minnesota
I went out before the storm hit and made a makeshift wire to run to battery ground results as follows with Ohm meter set at 200 ohm. May or may not be accurate I was in a hurry. LOL
A-12 - 1.1
D-1 - 1.1
D3 - 1.1
D-10 - Flashed between 10.0 & 10.5
_______________________________
A-11 - 0
B-3 - 1.1
D-2 - 0
I’ll double check these readings again when I get home.
A-12 - 1.1
D-1 - 1.1
D3 - 1.1
D-10 - Flashed between 10.0 & 10.5
_______________________________
A-11 - 0
B-3 - 1.1
D-2 - 0
I’ll double check these readings again when I get home.
Team Owner
Joined: Jan 2003
Posts: 20,324
Likes: 250
From: Summerland B.C. Canada
I went out before the storm hit and made a makeshift wire to run to battery ground results as follows with Ohm meter set at 200 ohm. May or may not be accurate I was in a hurry. LOL
A-12 - 1.1
D-1 - 1.1
D3 - 1.1
D-10 - Flashed between 10.0 & 10.5
_______________________________
A-11 - 0
B-3 - 1.1
D-2 - 0
I’ll double check these readings again when I get home.
A-12 - 1.1
D-1 - 1.1
D3 - 1.1
D-10 - Flashed between 10.0 & 10.5
_______________________________
A-11 - 0
B-3 - 1.1
D-2 - 0
I’ll double check these readings again when I get home.
Thread Starter
Pro
Joined: Nov 2009
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From: Maple Grove Minnesota
I have two meters go figure the one I used is bad. Using a good meter I adjusted the ohms reading to zero with the probes touching each other. When not touching each other the needle goes all the way to the left (highest reading). Here are the new readings.
A-12 - 0
D-10 – 0
D-3 – Did not move the needle
D-1 – 0
__________________________
A-10 – 20 ohms
A-11 – 7 ohms
B-3 – 0
D-2 - 0
A-12 - 0
D-10 – 0
D-3 – Did not move the needle
D-1 – 0
__________________________
A-10 – 20 ohms
A-11 – 7 ohms
B-3 – 0
D-2 - 0
Team Owner
Joined: Jan 2003
Posts: 20,324
Likes: 250
From: Summerland B.C. Canada
I have two meters go figure the one I used is bad. Using a good meter I adjusted the ohms reading to zero with the probes touching each other. When not touching each other the needle goes all the way to the left (highest reading). Here are the new readings.
A-12 - 0
D-10 – 0
D-3 – Did not move the needle
D-1 – 0
__________________________
A-10 – 20 ohms
A-11 – 7 ohms
B-3 – 0
D-2 - 0
A-12 - 0
D-10 – 0
D-3 – Did not move the needle
D-1 – 0
__________________________
A-10 – 20 ohms
A-11 – 7 ohms
B-3 – 0
D-2 - 0
How many wires are connected on your 87, not including the ground strap ?
Running a new ground wire from D3 to G104 will fix that, if you don't find a break.
How you ohmed D15 and D16, from ECM connector to injector connector ?