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Inertia switch-causing prob? disconnect?

15K views 19 replies 11 participants last post by  chuckb 
#1 ·
Could this be an inertia switch issue? This has happened to me a few times, all after driving the same road, same exact spot & situation.

I go down a twisty road, wait at red light, turn left go about 45mph and take a quick 90 degree right. after quick right with clutch still in, engine stumbles to 400 rpm and starts trying to catch itself, then is fine. I also noticed once on a gradual right hand turn it felt like it was bogging for a second.

It's done it probably 4 times, otherwise runs great. Car is the 93 in my sig.

Could the inertia switch get weak? Has anyone else had problems or bypassed it? Thanks.
 
#2 ·
It's not your Inertia switch. If it is/was tripped you'd have to reset it. I'd suspect maybe a fuel pump or a loose wire somewhere..I'd have the car running & shake EVERY wire in it. And if necessary move on to checking the FP while driving thru that curvy road....Generally U have to reproduce the symptom to diagnose it!!!
 
#3 ·
^thanks. I can't really tell if it's electrical or fuel related. what else could right hand turns affect? lol.
 
#5 ·
it did it with 3/4 tank once(that's the most I usually fill it). other times about 1/4 tank.
 
#6 ·
you could eliminate the possibilty of the inertia switch by jumping the switch over.i had a bad inertia switch on my 88 drive me crazy by cutting off and the switch never once popped up for me to reset it.i jumped the switch over and after i seen it fixed the problem i replaced the switch.switch 's can be bad even without popping up to cause a reset condition.
 
#7 ·
Check your battery cables and block grounds.
 
#8 ·
A few days ago I put on new battery terminals & tightened/checked all the grounds I could find.

It did it again once last night.

you could eliminate the possibilty of the inertia switch by jumping the switch over.i had a bad inertia switch on my 88 drive me crazy by cutting off and the switch never once popped up for me to reset it.i jumped the switch over and after i seen it fixed the problem i replaced the switch.switch 's can be bad even without popping up to cause a reset condition.
The inertia switch is in trunk? I think I'll just temporarily skip the switch a see if it does it again. Is there anything I need to know to jump the switch?
 
#9 · (Edited)
It very well could be the inertia switch. I was having the same problem in my autocross car. Halfway through runs, the engine would just cut out. Then it would start right up. It only happened when making a hard right turn or in slaloms. Didn't matter how much fuel was in the tank.

Went through everything: connections, fuel pressure, fuel pump, fuel lines, alternator, TFI, distributor, coil, harness, computer, fuses, etc. No problems there.

Bypassed the inertia switch and everything is fine now.

I was surprised how easy it is to make it pop open. Just by shaking it gently. Must have been a bad switch.
 
#11 ·
It's next to the drivers side taillight inside the trunk/hatch area
 
#12 ·
can you still buy a new inertia switch from dealer? anyone have an idea how much $ ?
 
#14 ·
my old car would throw it on hard launches drove me crazy not sure if it was a weak switch or if the 6500 launch wit huge tire were the cause lol
 
#15 · (Edited)
just got off phone with dealer. $22 with tax and they'll have it for me tomorrow morning.

I figured for $22 it'd be easier to just change it than have to mess with wires/plug twice jumping it and then waiting to see if it fixed etc...
 
#16 ·
My inertia switch would trip with a hard launch (low 1.5 60fts) and leave the car dead on the track. I bypassed it and haven't had the problem since. I'd say its the inertia switch but I thought when they trip they trip...not resetting itself.
 
#17 ·
I've also had a loose "tuna can" in the fuel tank cause this problem. The can acts as a sump for the fuel pump. If it comes loose, it will let the fuel slosh away from the pickup.
 
#19 ·
how do I check "tuna can"?

I put the new inertia switch in today, I guess I'll see if it ever does it again.
 
#20 ·
update:

been driving it a lot & car has not done it once since I put in the new switch.
 
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