C4 Death Trap
Safety Car
Joined: Apr 2016
Posts: 4,648
Likes: 1,059
From: N.E. Ohio OH
Finalist 2020 C4 of the Year - Modified
I have yet to crack open my gas tank. A while back before this all happened, I ran my tank dry all the way to the reserves without realizing. Soon after that my problems started arising
before you buy anything. Get a $6.00 transfer pump from Harbor Freight and stick the hose all the way to the bottom and pump some of the gas out into a clear glass jar then let it sit over night. If there is any water in the fuel, it will be visible.
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
Water in your gas will cause intermittent dying, especially if there is not a lot of it. So will other stuff. You can get condensation. Pull the pump and look at the filter to see if it is clogged up
before you buy anything. Get a $6.00 transfer pump from Harbor Freight and stick the hose all the way to the bottom and pump some of the gas out into a clear glass jar then let it sit over night. If there is any water in the fuel, it will be visible.
before you buy anything. Get a $6.00 transfer pump from Harbor Freight and stick the hose all the way to the bottom and pump some of the gas out into a clear glass jar then let it sit over night. If there is any water in the fuel, it will be visible.
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
Replaced the fuel pump just now, pressure up again, but it is not starting up. Only turning over at the moment.
Also, I have a fuel pump relay for it, but don't have the time right now to replace it. I had already bought it in advance, so I figured I might as well go ahead and replace.
Also, I have a fuel pump relay for it, but don't have the time right now to replace it. I had already bought it in advance, so I figured I might as well go ahead and replace.
Last edited by Mason8383; Mar 4, 2021 at 07:10 PM.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Replaced the fuel pump just now, pressure up again, but it is not starting up. Only turning over at the moment.
Also, I have a fuel pump relay for it, but don't have the time right now to replace it. I had already bought it in advance, so I figured I might as well go ahead and replace.
Also, I have a fuel pump relay for it, but don't have the time right now to replace it. I had already bought it in advance, so I figured I might as well go ahead and replace.
Last edited by aklim; Mar 4, 2021 at 08:02 PM.
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
My motor was turning over and I had pressure in the fuel rails. I cant test for my injectors until I get it running. I will try starting it with starting fluid tonight then.
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Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
I see. Well, I put my NOID light tester on each injector on my car and did not get any lights coming on at all. Could that mean a bad optispark? I'm still going to check for power from the opti, but could it be a symptom?
Drifting
Joined: Apr 2020
Posts: 1,925
Likes: 610
From: Orange, CA
No injectors means the PCM isn't sending any injector fire signals. That's probably going to be no timing signal from the optical sensor on the optispark. The question however is whether that's an issue in the optical sensor itself, an issue with the wiring harness between the opti and the car, or an issue in the harness between the opti harness and the PCM. Somewhere, the timing signal isn't getting from the optispark to the PCM.
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
No injectors means the PCM isn't sending any injector fire signals. That's probably going to be no timing signal from the optical sensor on the optispark. The question however is whether that's an issue in the optical sensor itself, an issue with the wiring harness between the opti and the car, or an issue in the harness between the opti harness and the PCM. Somewhere, the timing signal isn't getting from the optispark to the PCM.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Of course it could be fried but before we go there, lets see if it is an opti issue. The more parts you throw at it, the more variables you throw at the equation.
Drifting
Joined: Apr 2020
Posts: 1,925
Likes: 610
From: Orange, CA
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
Hi everybody, it has been a while since I have updated this forum, school has been holding me back from working on it. Anyways, here what I got:
- Tested both ECU's, have the same no start symptoms with both
- Tested for spark, no spark
- NOID light test, no injectors lit up
- Bought a new ICM and plugged it in, still the same
- Replaced fuel pump, same symptoms
- Tested fuel rails, good pressure
- Took off the plug from the ignition coil and held it close to the coil tower and no spark arched.
- Stuck test light into opti plug and grounded on coil tower, turned the engine over and no light.
Keep in mind I have replaced the ignition coil, ICM, Opti-spark 3X, spark plugs, plug wires, fuel pump, and ECU (both ended up working). I have not tested the opti yet, so I will go ahead and do that now. Please, if anyone has an idea on this let me know what you think.
- Tested both ECU's, have the same no start symptoms with both
- Tested for spark, no spark
- NOID light test, no injectors lit up
- Bought a new ICM and plugged it in, still the same
- Replaced fuel pump, same symptoms
- Tested fuel rails, good pressure
- Took off the plug from the ignition coil and held it close to the coil tower and no spark arched.
- Stuck test light into opti plug and grounded on coil tower, turned the engine over and no light.
Keep in mind I have replaced the ignition coil, ICM, Opti-spark 3X, spark plugs, plug wires, fuel pump, and ECU (both ended up working). I have not tested the opti yet, so I will go ahead and do that now. Please, if anyone has an idea on this let me know what you think.
Drifting
Joined: Apr 2020
Posts: 1,925
Likes: 610
From: Orange, CA
Your PCM isn't getting the timing signal from the optispark, as many said before. Now it's time to find out if that's because the opti itself is bad (you having gone through three is irrelevant if they were all parts store specials), if the opti harness is bad, or if the vehicle-side harness is bad.
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
This is good stuff. In the meantime, I was wiggling wires between my ecm and opti and my car started. I pressed down on one of the places where I shifted them and it cut out twice in a row. Now it won't start again.
Drifting
Joined: Apr 2020
Posts: 1,925
Likes: 610
From: Orange, CA
Your PCM isn't getting the timing signal from the optispark, as many said before. Now it's time to find out if that's because the opti itself is bad (you having gone through three is irrelevant if they were all parts store specials), if the opti harness is bad, or if the vehicle-side harness is bad.