My 87 TII used to turn off when I got it, though it had a turbo timer. I uninstalled the turbo timer and now it won't turn off when I pull the key and I have to kill it with the clutch. I searched and a few peope have said it was due to plugging in the ignition harness wrong, but I have the wires all going to matching wires so I can't figure it out. My old ignition harness was hacked up so I got a new one but that didn't fix my issue. Any ideas?

Btw my engine harness is kinda hacked up too..but I haven't changed anything in the engine.

 

Too difficult to tell not being there and knowing just what items were disconnected/reconnected.

Most of these ENGINE WON'T TURN OFF threads are caused by one elect plug being connected to another plug and that OTHER plug was never meant to be connected to the first plug.

This usually results in the battery buss in the interior fuse box backfeeding the IG1 ignition buss in the interior fuse box which results in the key being totally worthless when it comes to turning the car off.

These plugs that should never be mated to each other are near the throttle/clutch/brake pedal in MOST cases.

Another case is where the alternators two wire small plug has the two wires swapped in the plug or if the plug does not exist anymore......the two wires connected to the alternator in the wrong places. As in the b/w going where the w/b wire should go on the alt backside.

Next time the car won't turn off...............go to the batt bus in the interior and pull one batt buss fuse at a time til the engine dies. Let us know which fuse caused the engine to die.

BAtt buss on a series four is the top two rows of fuses.

Or maybe just pull the BTN in the engine bay fuse box and see if the engine dies. The BTN feeds the batt buss in the interior fuse box. IF this pulling results in the car dieing..............then put the BTN back in and go to the step above this and pull one batt buss fuse at a time and let us know which fuse did the job. We can trace it from there.

 

I unplugged all the batt buss fuses and the car still ran without the key. I pulled the BTN fuse and it still ran as well. Just to clarify when I kill my car with the clutch after removing the key the car turns off like it should. (No idiot lights or beeping)

 

Well. got me. Try this. Remove the small two wire plug off the alternator (yes, I know its a pain with the intercooler in the way a bit).

Then start the engine for a minute or so and then turn the key OFF. What happened?

The reason the engine dies on a NORMAL RX........................the ignition switch feeds the ENGINE fuse in the interior when the key is put to ON or better. This in turn powers the MAIN RELAY which pulls in and feeds the coils, ECU, fuel pump and assorted stufff.

So when you put the key to OFF the MAIN RELAY relaxes and no power will go to the ECU or the coils and..stufff so the engine dies for obvious reasons i.e. no spark, no fuel, no nothing important other than some lights etc.

Usually a batt buss fuse backfeeding the IG1 fuse row (where the ENGINE FUSE exists) will mean the engine won't die if the key is put to OFF.

Another thing that can cause backfeeding is the alternators two wire plug being crossed up somehow. So.......try the above suggestion by pulling the alt plug off. Takes but a few minutes.

Another possible thing would be if the MAIN RELAY does not relax when the key is put to OFF. That would mean the two EGI FUSES in the engine bay would keep on feeding the ECU and coils and stuff.

Might have then engine running............key to OFF.............then IF the engine still runs, pull one or both of the EGI fuses and see if the car dies. Should.

So play makebelieve withe me a say the engine dies when the EGI fuses are pulled. That would make me thing the MAIN RELAY is not relaxing when the key is put to OFF. Key to OFF means there is no power from the ENGINE fuse to the MAIN RELAYs coil so it should have relaxed.

To prove this relay is bad...............get access to its two elect plugs. Pull apart the one with two wires going to it. If the engine still runs.......pull the four wire plug on that relay apart. Car MUST die when doing that. If not.............major miswire in that car that cannot be fixed from this keyboard.

Got a meter? Simpel meter will do. IF so things get easier. Enigne running......key OFF.........pull the two wire plug to the MAIN RELAY. See if there is batt voltage on the black/white wire in that two wire plug. IF no batt voltage and the engine is still running..........MAIN RELAY IS sticking. Get new one. DO NOT just go out and buy a new relay. Do this test first. No need to waste money.

I'd do this last part first IF you have a simple meter laying about. Main Relay is near the brake master cylinder attached to the fender or close by. Has two elect plugs. One with two wires.......one with four wires. On a normal car pulling apart either one with engine runnning will kill the engine.

 

Here's a thought. Look at the jpg I attached earlier of the fuse box in the interior.

See IG1 row of fuses and how the ENGINE , METER, TURN are all on that row??? Say yes. Well when you turn the key to OFF do the gauges go off? Like tach to zero ?????? and do the TURN signals still work with the key to OFF? (normal car they won't work with key OFF.)

IF the gauges (meter fuse powers them) and Turn signals all work, that means there is something powering that row of fuses other than the ignition switch and the problem is NOT the MAIN RELAY being stuck closed.

Might check this out prior to doing any other item I suggested above.

IF the gauges and turn signals do not work with key to OFF but engine still runs.......then the MAIN RELAY is most likely bad. Check it with a meter like I suggested earlier.

 

OR.......with key OFF and engine runing, pull the ENGINE fuse in the interior. IF the engine still runs, then the Main Relay is stuck most likely (barring a major wiring miswire in the car).

 

I'll go ahead and try the alternator wires...made me think and I remember that part of my engine harness was all chopped up. Maybe I reversed the wires. Check this out:

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/these-correct-wires-alternator-s4-981170/

I didn't do any of that crimping. The wires fell out and I had to solder them up. Maybe I reversed them or something. I could use a new engine harness, but it's gonna be a PITA to install.

EDIT: I'll check out all of the above though when I get a chance. My tach still works when the car is running with the key OFF too.

 

Dayum dude! New harness is in your future

 

Tach still working with the key off means something is backfeeding the IG1 buss in the interior fuse box.

Turn signals probably still work with the key off since they are on the same buss bar as the ENGINE, METER AND TURN signals. They should NOT work with key OFF.

Series four alternators get two wires on the plug on the back. The BLACK/WHITE one is on the top. The WHITE/BLACK is on the bottom.

Swap those two around and you get a car that won't turn off with the key because the alt is backfeeding the IG1 fuse buss in the interior.

 

We have a winner! It was the alt wires crossed. THANKS A TON MAN!