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AndrewB23 06-11-2019 05:35 PM

Car dies randomly and under heavy braking
I just got my 98 rs back up and running after the previous owner decided to only get one head machined and left the other alone which caused weird compression and threw everything out of whack, but now that's solved I'm encountering a new problem with the car just dying randomly while driving/stopped and also under hard braking, when I brake before it happens the oil light comes on very slowly for a brief second and then all the lights come on because it died. If anyone has had this issue or atleast knows how to fix it I would love advice.

Jack_Stalk 06-11-2019 09:18 PM


silverton 06-12-2019 08:28 AM

checking post history, looks like an auto to manual swap. what do you mean the light comes on slowly? like dim to bright? the bad boy triggers at only like 2-3psi. is your oil filled to spec? Keeping enough gas in it? I know these like to fuel starve in high g situations.

2nd25RS 06-12-2019 09:06 AM

Does it die while cruising or only when stopped/coming to a stop (only when idling)? I would check for intake leaks and take a look at the idle air control valve.

AndrewB23 06-12-2019 10:10 AM

It's manual swapped, the light comes on very slightly dim and then everything lights up when it dies, it doesn't happen everytime and the oil is full. My fuel tank is full too that actually caused another issue of my gauge being pegged at full and throwing a low fuel sensor level code. The car dies whiling driving or at a stop, it hasnt done it when just parked and letting it idle. I was suggested to try a different maf sensor, I did and it still dies. I've also notice sometimes the battery comes on first sometimes then dies.

yarrgh 06-12-2019 11:27 AM

Sounds like a loose wire somewhere. Perhaps the force of slowing the vehicle is just enough to break a circuit.

It could also be the IACV being slow to react. Does this occur if you've been coasting for a few seconds and then try to stop. Although that might not do it since you're off the throttle and the IAVC has time to settle.

If you're stopped in neutral and you rev the engine and let off the throttle quickly, does the behavior show itself?

SoCoNoHa 06-12-2019 11:36 AM

My vote is iacv, although sometimes I swear it's related to break signal input. Mine is manual swapped and will stall very rarely, at the same two stops. One is down hill to a stop sign, the other is an off ramp, and it always happens after long periods of engine breaking, followed by shifting to neutral and applying the break.

Couldn't hurt to double check your wiring.

AndrewB23 06-12-2019 12:10 PM

Someone else suggested the IACV too they said to just clean it and if that doesn't work try a different one. I'll try those and see if it helps

AndrewB23 06-12-2019 12:19 PM

If I'm stopped and rev it the problem doesn't occur, it's only while driving, coming to a stop or sitting at a stop light. There is no consistency either, it happens when it feels like it. Sometimes it happens quick or it takes a while. I don't know if this helps with people trying to help me but it does run rich and has a consistent miss on 1&3 cylinders, but there's no rough idle, idk if those issues together mean one thing specifically, but I'll keep trying things

silverton 06-12-2019 12:24 PM

Is the check engine light flashing?

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