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FD broke down at track

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Old Jan 21, 2013 | 01:15 PM
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CA FD broke down at track

During a hard breaking left turn my FD shut down on me (had over 1/2 tank). It would not start and i had to be towed off. After letting it sit for an hour or so i managed to get it to restart but it is now shaking quite bad and appears to be misfiring. If i gas it hard it will turn off. If i slowly get on the gas it revs fine and the vibration goes away.

Car info: 93 rx7, 130k, PFC, intake exhaust rest is stock

Tonight/tomorrow im going to start with checking the spark (im thinking maybe a bad coil) then ill move on to fuel, then check compression.

Is there any diagnostics i can run with PFC? or any similar experiences? or suggestions? thanks ahead of time
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Old Jan 21, 2013 | 08:14 PM
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checked spark and its good, whats a good way to check for fuel? ill dig into my service manual as soon as i get a chance
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Old Jan 21, 2013 | 11:15 PM
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I'd also check for vacuum leaks, maybe a hose popped off.

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Old Jan 22, 2013 | 05:05 AM
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*With a PFC you don't get and CELs. Go to the SENSOR screen on the Commander and see what's shaded.
*Check the vacuum line at the MAP sensor. Make sure it's connected at both ends.
*Do a compression check.
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Old Jan 22, 2013 | 02:12 PM
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Anyone near upland CA (i will pick up) have a compression with a quick connect (end is rubber and you just jam into spark plug hole). I'm having a **** of a time using the screw in type.
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Old Jan 22, 2013 | 02:41 PM
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Remember, you want 3 relatively equal pulses per rotor. Ideally you'd want to see something around 100 psi, but a little lower or higher isn't as important as having relatively equal pulses.
Make sure your battery is fully charged or put it on a charger.
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Old Jan 22, 2013 | 03:28 PM
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Do the easy compression check. Pull a trailing plug and the EGI relay. Crank and listen for 3 even pulses. Repeat for other rotor.

Here's a bit more thorough explanation. Is My Engine Blown?
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Old Jan 22, 2013 | 08:29 PM
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did easy test and doesnt sound good. front rotor 3 even pulses, rear rotor appears to only pulse once. Damn
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Old Jan 22, 2013 | 10:15 PM
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That sucks man. When it runs does it have a hard time holding idle?

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Old Jan 22, 2013 | 10:20 PM
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Fuel surge lean out detonation. apex seal go bye-bye
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Old Jan 23, 2013 | 12:19 AM
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If he was braking and not hitting the gas how would he go lean??

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Old Jan 23, 2013 | 09:35 AM
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It will stay on and idle but shake really bad. Im thinking it did go lean on that hard breaking turn. I had a little over 1/2 tank.
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Old Jan 23, 2013 | 10:17 AM
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Originally Posted by donrafa7
It will stay on and idle but shake really bad. Im thinking it did go lean on that hard breaking turn. I had a little over 1/2 tank.
That sucks man. You'll have to do something to prevent it from going lean next time

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Old Jan 23, 2013 | 11:21 AM
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Could also be that you were tracking a 130k mile engine. Of course you are going to go lean when braking, the ECU cuts fuel. Well...unless you were super left foot braking.

More likely it failed during the acceleration before the turn. But at this point, it's really it doesn't matter much.
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Old Jan 23, 2013 | 11:55 AM
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engine had 30k on rebuild (from previous owner with paperwork). id still like input though as i would like to prevent this after rebuild. You might be right in that it popped before turn, before the turn there is a long 110mph WOT straight.
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Old Jan 23, 2013 | 12:51 PM
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It's probably too late now, but you could have looked to see what your peak boost level was on the PFC Commander. If it wasn't simply an internal failure, that might have told the story....a spike or creep. Exactly what intake and exactly what exhaust modifications? Any fuel mods?
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Old Jan 23, 2013 | 12:53 PM
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Didn't someone sell a fuel tank baffle a few years back that eliminates slosh and keeps the pump from sucking air?
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Old Jan 23, 2013 | 02:33 PM
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Apexi dual intake, RB exhaust, rx7store downpipe. I didn't see what it was on the straight but Boost would never go above .75 on street
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Old Jan 23, 2013 | 03:57 PM
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This thread has me wondering if the same thing could happen on an fc.

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Old Jan 23, 2013 | 07:17 PM
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Originally Posted by donrafa7
Apexi dual intake, RB exhaust, rx7store downpipe. I didn't see what it was on the straight but Boost would never go above .75 on street
Do you have a cat or running a mid-pipe?
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Old Jan 24, 2013 | 09:33 AM
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Cat
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Old Jan 24, 2013 | 09:49 AM
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which side is the fuel pick up on in the tank?
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