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86 not running right

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Old Nov 24, 2013 | 08:27 PM
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Default 86 not running right

86 CORVETTE,
383, stock TPI with bosh 3 injectors, Holley adjustable fuel pressure regulator, accel throttle body, K&N air filter, exhaust manifolds opened up, true dual exhaust, bullet cats, air pump deleted, EGR deleted, 91 vert mufflers, 94 corvette alternator, 170 thermostat, MSD cap and rotor, MSD plug wires, Bosh III platinum plugs.

It started when I was on the freeway about 80 mph, around 1800 RPM, the engine quit, and I rolled off the freeway onto the off ramp, I tried to start it when I got it stopped by the side of the ramp.
I was later towed home on a flat bed, and because I did not have any fuel pressure, I bought a fuel pump, and installed it.
The car started after a long cranking session, and I drove it around the block, then parked it in front of the house.
Next day, I backed the truck out of the garage, drove the 86 into the garage and shut it off.
that night, I was going to switch the 86 and the truck, and it wouldn't start.
I played with it a little, and because I had a spare distributor, I changed it. It did not start.
I pulled the coil out, and the wires had vibrated off the coil!
I had the original coil, so I installed it, and the car started up and ran pretty good.
The next day, I drove it to work, and halfway there (8 miles) it started to run rough. after work, drove it home, missing on maybe 2 cylinders.

HERE IS WHERE I AM NOW:

the left muffler is dripping 3 times as much water as the right.
no codes.
shorted A&B while running, check engine light flashes fast.
I checked the plug wires, and then pulled plugs. #1 was all fouled out.
I installed a new plug in #1, and no change.
I swapped the original distributor back in, no change.
I changed the #1 spark plug wire, no change.
I changed the rotor, no change,
rerouted the plug wires in case they were shorting to something, no change.
the whole time I am troubleshooting, I had a fuel pressure gauge on it, and 44 PSI until I goose it, then 47 PSI.
exhaust really stinks.
pulled the mas air sensor out of the snorkel, no change,
tapped on mass air sensor, mass air sensor relay, distributor, and esc box. no change.
It acts like one cylinder is not firing.
#1 plug looks like no fuel, but smells like fuel.
Next option is to change all spark plugs in case one got fuel fouled.
Any suggestions?

Last edited by coupeguy2001; Nov 25, 2013 at 12:20 AM.
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Old Nov 24, 2013 | 08:44 PM
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your Fuel Pressure Seems Too High. Pull The Vacuum Line Off The Regulator, If There Is Gas In The Line It Is Shot. Are These The Original Injectors?
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Old Nov 24, 2013 | 09:51 PM
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fuel pressure is ok, I used to run 45/50.
as stated, bosch 3 injectors (yellow ones) about 2 years old, maybe 25,000 miles on them
no gas in vacuum line
oh, it is a Holley pressure regulator.
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Old Nov 24, 2013 | 10:01 PM
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Two things come to mind:

Bosch III? Platinum Plugs wouldn't be my first choice, try another plug.

Have you checked that your injectors all firing (noid light test)?

alibi
Maybe check your injectors (yes, new Bosch 3, I know). Or have someone flow check them.

Last edited by DanZ51; Nov 24, 2013 at 10:04 PM.
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Old Nov 24, 2013 | 10:16 PM
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Did not realize you had an AFPR. Maybe the injector in cylinder 1 is leaking? How is your o2 sensor? Black, rusty, or grayish?
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Old Nov 25, 2013 | 12:12 AM
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I suspected the plugs, looked at them. put them back in, except changed no. 1. # 1 was all crudded up like the injector was leaking or the spark was weak on that cylinder.
Tomorrow night after work, I will change the rest of them.
I ordered new wires, since I had to change two of them.
did not look at O2 sensor since the check engine light was flashing fast indicating a rich condition, telling me that it was working.
I have a spare injector that I can use to check the # 1 injector if I have to.
do not have a noid light, but will use a volt meter to check.
I did check fuses when this all started.

Last edited by coupeguy2001; Nov 25, 2013 at 12:24 AM.
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Old Nov 25, 2013 | 03:31 AM
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Originally Posted by coupeguy2001
did not look at O2 sensor since the check engine light was flashing fast indicating a rich condition, telling me that it was working.
I don't think that is correct. Here is what I found in the '86 FSM (page 6E-6):

"In Open Loop the "SERVICE ENGINE SOON" light flashes two and one-half times per second.

"In "Closed Loop", the light flashes once per second: Also, in "Closed Loop", the light will stay OUT most of the time if the system is too lean. It will stay ON most of the time if the system is too rich."
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Old Nov 25, 2013 | 07:24 AM
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Since cylinder #1 is your problem pull the valve cover and make sure your valve train is in proper working order.
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Old Nov 25, 2013 | 08:04 AM
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Originally Posted by coupeguy2001
I suspected the plugs, looked at them. put them back in, except changed no. 1. # 1 was all crudded up like the injector was leaking or the spark was weak on that cylinder.
Tomorrow night after work, I will change the rest of them.
I ordered new wires, since I had to change two of them.
did not look at O2 sensor since the check engine light was flashing fast indicating a rich condition, telling me that it was working.
I have a spare injector that I can use to check the # 1 injector if I have to.
do not have a noid light, but will use a volt meter to check.
I did check fuses when this all started.
Even if the computer was reporting a rich condition, the o2 is what tells the computer that it is rich. If the o2 sensor is broken, it can report a rich reading to the computer consistently and the computer would report a rich condition just the same as if it was working properly.
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Old Nov 25, 2013 | 10:16 PM
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changed all plugs. no change.
valve train:
had a problem a couple of months ago, the rocker studs that came with the heads were breaking off. Bad heat treat. (like the titanic, the metal fractured and shattered.)
changed the rocker studs and adjusted valves then. Doesn't mean it can't be valve adjustment, so I will check that they aren't too tight, holding open a valve.
Check engine light:
you are right, I was using another person as my reference, and they got it wrong, I was just repeating bad information. I looked it up and yup, GIGO.
O2 sensor:
the wire coming out of it looked a little askew. tried to move it with my fingers, but it seemed tight.
It has been a while since I changed it, (maybe 7 years) so now might be a good time to replace.
It is starting to look a lot like #1 injector.
Going to pull #1 plug again after a short run and see what it looks like, but I have injector in hand, and a spare set of o rings and gaskets for the fuel rail and intake, so I will try the valves and the injector first.

Last edited by coupeguy2001; Nov 25, 2013 at 10:19 PM.
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Old Nov 25, 2013 | 10:44 PM
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Ok, went out and pulled #1 spark plug after another brief start.
plug was all wet with fuel.
commencing to disassemble fuel rail and intake.

As memory serves, I bought the injectors from Jon at FIC.
I sent an email to the company, and he responded at MIDNIGHT his time, he is going to send me another set tomorrow since mine were under his 3 year warranty.
Great service!
can't beat that with a stick!

Last edited by coupeguy2001; Nov 25, 2013 at 11:24 PM.
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Old Nov 25, 2013 | 11:33 PM
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I am confident that is your problem. A leaking injector. But we'll see, keep us updated!
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Old Nov 26, 2013 | 03:02 AM
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If the #1 spark plug is wet with fuel I'd be more inclined to think the plug is not firing.
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Old Nov 27, 2013 | 12:11 AM
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I changed the spark plugs and #1 wire, distributor, (ie module and pickup coil) esc, ignition coil, swapped injector connectors between 1 & 3, checked all plugs twice, swapped plug wires between #2 and #1, checked voltage to distributor from the key, new fuel pump, pressure is 43#, took off gas cap, plugged EGR, adjusted IAC, I am out of ideas.

It has been a while since I changed the cap, but it looks good. I might just get one, even though I don't think I need it. If it is good, I can still use it on my 57 chevy truck.

I don't want to take the fuel rail apart till the injectors show up since I can move the car the way it is.
The new plug wires should be here tomorrow anyway.

Last edited by coupeguy2001; Nov 27, 2013 at 12:30 AM.
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Old Dec 13, 2013 | 07:53 PM
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ok, it has been a while since I did anything to the engine, so it was probably time for a tune up anyway.
As you read, it quit on the freeway, I changed the fuel pump and the ignition coil, and it ran really bad. missing on number one.
changed dist. cap, changed to a different stock coil, plugs, wires, distributor, and No. one was still not firing.
Changed injectors, and now no. 1 is firing. 43 PSI on the fuel pressure. But I dropped it to 40.
with everything I did, it still acts bad at idle. not cutting out any more, but it idles bad, and exhaust stinks really bad.
I had a spare maf, so I swapped it, I had a spare esc, so I swapped it.
I had a couple spare coils, so I swapped it again, this time, it seemed to run a lot better, but really bouncing around at idle.

I checked the EGR pipe, and it seemed pretty warm for being blocked off, so I have to try to make sure it is blocked off with another piece of aluminum that is larger, and maybe some header gasket material for a positive seal.
I haven't tried to drive it yet, but it seems like a waste if I don't get a decent idle.

No codes......no leaks......checked the engine grounds at the back of the block and added one to the alternator to ground.

The only thing left is to re-adjust the valves incase one or two of them are too tight.

so, now I am out of ideas.

Anybody?
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Old Dec 13, 2013 | 08:57 PM
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I knew it was that injector! Did you check your timing? Is your TPS voltage set properly? Maybe change your fuel filter now as part of that tune up.
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Old Dec 13, 2013 | 09:37 PM
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........ Generally , rocker studs will break when the valve springs are coil bound ... check that carefully , and make sure you check the inner springs/dampers ... if you are still getting water out of one side its time to do a compression test ... sounds like a blown head gasket to me .............
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Old Dec 14, 2013 | 12:28 AM
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did not check TPS voltage. I didn't feel that that it was a concern, since the coil wires broke. As for timing, Remember, I changed distributors, then put the original one back in. So maybe I 'll check the TPS voltage tomorrow, and try adj. the valves.

this engine has consistently dropped water out of the exhaust. currently, the water is the same for both sides.

Remember, it was running just fine when it quit on the freeway. the reason it quit was the wires on the ignition coil broke off. I think the fuel pump was still working. but the engine wasn't running at all till I changed the coil, the pump pressure is right on, and I can adjust it up to 50 PSI if I want, because I tried it. It does not run any worse or better.

Timing does make a difference.

Right now, I think the idle is bad, but the engine revs really quick, and I haven't driven it since it is low on gas and I have to get a couple gallons to get it anywhere to fill up.

Last edited by coupeguy2001; Dec 14, 2013 at 12:41 AM.
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Old Dec 14, 2013 | 12:38 AM
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Okay are you running water in your engine or antifreeze? It is probably just because it is really cold out now, my car spits out water too and it fine, it's just condensation. If you notice a loss of coolant/water then you have a problem. Can you give us some more details on how it is running rough? Does it accelerate smoothly or is it only at idle? Maybe take a video?
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Old Dec 14, 2013 | 12:52 AM
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accelerates smoothly, no coolant light, and I checked the coolant back when it all started and it was good, running antifreeze 50/50.

not sure on the video thing my phone does not seem to get the sounds right on noise of any kind.
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