Issue Summary:

After removing the upper intake manifold on my S4 RX-7 to access and clean the ECU ground, I reassembled everything as it was (to the best of my knowledge). I followed this video as a reference: .



Symptoms:

• After reassembly, the car would start and run for about 2 seconds, then immediately die.
• After a few starts like that, the starter stopped engaging when I turned the key.
• I pulled the starter and tested it — it still works fine.
• The fuel pump runs continuously at full speed (even with the key on), which floods the engine and drains the battery.
• The starter positive terminal shows 12V, and the starter control terminal also reads 12V.
• I cleaned all starter connectors and terminals, along with the battery terminals, and added an extra battery ground.

Current Behavior:

When the key is turned to “Start,” the starter doesn’t engage. However, if someone holds the key in the “Start” position and I manually jump the battery terminals, the car will crank and start — but only runs for about 2 seconds before dying again. After that, it won’t start from the key alone.



Notes:

• The car ran briefly after the manifold reinstallation, so something related to the wiring, grounding, or fuel system might be off.
• Battery is charged and connections are solid.

Any help diagnosing this would be appreciated. I’m especially not sure how to approach the fuel system issue since the pump seems to be overactive and flooding the engine.

 

sounds like you have the typical weak ignition switch issue along with a vacuum leak you created.


if the starter clicks but wont turn, a starter booster relay would fix that.

check all your vacuum lines, especially the big ones like BAC valve and the OMP port air line.

 

ok so bac valve voltage is 9.73 volts not sure if this is normal or not, and the starter also doesn’t click at all but only goes when I jump them the terminals on it it turns the engine over. And with the vacuum leak I’m not sure how to test that if someone could help me. And for the ignition switch could it really go bad like that if the battery gets low and it would stop working. Could it be the starter solenoid or relay?

 

Have you checked your battery voltage?

Did you tighten the battery terminals?

 

Yes it’s 12.43 v if the battery is bad could it be a reason?
and I’ve replaced the terminals on the battery

 

I second vacuum leak being made when you worked on intake. That would cause it to sputter and die.

For starter issues gotta be battery or solenoid assuming you havent shorted the wires out. get a different battery then return it to the store if that isnt the issue. Too simple to not try.

Adding relay is something people do. Banzai racing still carries a kit for the click click no start issue

 

I’ve tried a different battery and I’ve jumped the starter terminals and it cranks then and etc. I’m confused why the car won’t start when I turn the key to the start position there’s no clicking from the solenoid and only clicking from the passenger footwell and just the fuel pump running at full blast.

 

I found the thing that was clicking on the passenger floor well does this look factory or not? The fuse inside of it was blown

 

Not quite sure what that thing is. Looks like it says ABS on it. I dont have ABS so makes sense ive never seen it

 

Ok so I got a new starter solinoid and when I put it in it started getting hot after like 2 mins and so then I took it off and then when I took it off smoke poured out of it and I should mention that the original starter solinoid smelt very burnt. If someone could possibly guide me through fixing this it would be very helpful