95 C4 base died now no spark
Thread Starter
5th Gear
Joined: Sep 2024
Posts: 5
Likes: 0
95 C4 base died now no spark
Hey all Im new to owning my C4. I was driving a few weeks ago and the engine just shut off like I turned the key. Then would not start. I got it home found I had no spark so I did the opti with a new coil, plugs, and wires. Still no spark from coil or plugs. I put in a summit racing opti as they had good reviews. I have checked for voltage to the coil I'm getting 4ish volts to the A side. I don't know if I'm missing something.
Thread Starter
5th Gear
Joined: Sep 2024
Posts: 5
Likes: 0
No I haven't I ordered one. I have seen people talking about jumping it to test if that's the problem but haven't figured out how.
Racer
Joined: Jul 2023
Posts: 256
Likes: 87
I'm not familiar with how that is done 🤔 $20~$40 part depending on where you source it tho. Not worth the "electrical adventure" in my opinion 😕 I've "heard" that it does have to be mounted for proper grounding tho. Have to actually bolt on the new one before you try it. Good Luck with it👍
Thread Starter
5th Gear
Joined: Sep 2024
Posts: 5
Likes: 0
Ok so now it's running. However I have a nasty miss fire. I believe it's coming form 7 or 8. In my computer software I can turn off cylinders. I turn off 8 no change, turn off 7 it smoths out. The car is popping out to exhaust. And I can smell raw fuel. I tried checking my plugs and wires. But the engine is hot so I'll do that tomorrow. However could I be out of time on my opti? I put that little pin off the cam in the rectangle shape hole? Just a little bit confused 🤔.
Melting Slicks
Joined: Nov 2016
Posts: 2,256
Likes: 3,083
From: So Cal
2023 C4 of the Year Finalist - Unmodified
The LT1/4 ICM is not a "$20 part". I've bought 2 Delphis from rockauto in the past 12 months. With tax and shipping they were $165 each.
OP: Check your firing order on the plug wires. Pretty easy to get a couple mixed up, and will cause the problems you are experiencing. Usually one pair like 5&7, 6&8, etc are backwards.
OP: Check your firing order on the plug wires. Pretty easy to get a couple mixed up, and will cause the problems you are experiencing. Usually one pair like 5&7, 6&8, etc are backwards.
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Thread Starter
5th Gear
Joined: Sep 2024
Posts: 5
Likes: 0
The LT1/4 ICM is not a "$20 part". I've bought 2 Delphis from rockauto in the past 12 months. With tax and shipping they were $165 each.
OP: Check your firing order on the plug wires. Pretty easy to get a couple mixed up, and will cause the problems you are experiencing. Usually one pair like 5&7, 6&8, etc are backwards.
OP: Check your firing order on the plug wires. Pretty easy to get a couple mixed up, and will cause the problems you are experiencing. Usually one pair like 5&7, 6&8, etc are backwards.
Advanced
Joined: Mar 2023
Posts: 69
Likes: 71
Fuel Control Module!
I would agree. I went through $1,200 in a new opti and other stuff before my trusted mechanic realized it was this $149 part.
Melting Slicks
Joined: Nov 2016
Posts: 2,256
Likes: 3,083
From: So Cal
2023 C4 of the Year Finalist - Unmodified
The opti plug towers are from top to bottom:
Passenger side: 4 - 6 - 8 - 2.
Driver side: 5 - 3 - 7 - 1
The passenger side isn't too tough to trace the wires, or reach the opti.
The driver side is tight. "Removing the balancer" doesn't get you anywhere for access to the plug wires.
First, I'd consider removing the forward inner wheel housing. Just a few 10mm head bolts. That may give access to see and change the wires. Another strategy may be to remove the belt, idler, and tensioner. Last resort would be to remove the compressor bolts and brackets and lift the compressor up. That shouldn't be necessary. I've seen reports on here that peeps were able to reach the driver side wires from under the car. It's a long reach and a lot of stuff like steering and sway bars is in the path; I've looked, but never tried it.
And the last "Duh" for the next time you R&R an opti: After the opti and plug wires are on, fire it up! Be sure it runs correctly before you continue to put all the other stuff back on and refill the coolant.
Burning Brakes
Joined: Jun 2022
Posts: 845
Likes: 212
From: Florida
