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  1. #11
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    WELL, the Bank 2 O2 was flat black, the other looked pretty good, I cleaned out the black one with MAF sensor cleaner and swapped them.

    I also checked my fuel pressure reg and sure enough I can smell fuel in the vacuum line going to it, so I ordered a new one.

    And I also had to order a new driver side mirror glass, because while I was washing it, I accidentally gave it the peoples elbow...
    97 Trans Am WS6, LT1 factory 4bolt freak, M6,
    68 Firebird 400, YC 400, 670 heads M4
    14 Fiat 500e
    , 83kW motor, 24kWh 364 V battery

  2. #12
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    So I changed out the fuel pressure reg and O2s yesterday, its running better, but misfire is still there....

    its jumping between Cylinder 1 and 3. I am really really hoping its not the opti.

    I have an MSD unit, so I am going to shoot their techs an email and ask where the timing adjustment screw should be set at.

    it has a bit of hesitation at lower RPMs but clears up at 2200-2500.

    If I have it in 5th or 6th gear and give it gas it shakes like crazy
    97 Trans Am WS6, LT1 factory 4bolt freak, M6,
    68 Firebird 400, YC 400, 670 heads M4
    14 Fiat 500e
    , 83kW motor, 24kWh 364 V battery

  3. #13
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    Quote Originally Posted by captainofiron View Post
    I have an MSD unit, so I am going to shoot their techs an email and ask where the timing adjustment screw should be set at.

    it has a bit of hesitation at lower RPMs but clears up at 2200-2500.

    If I have it in 5th or 6th gear and give it gas it shakes like crazy
    IDK how old your MSD opti is....but they recently have had a huge rash of issues with their Opti's

    if you are throwing 0301 and 0303 codes cyl 1 & 3 are misfiring (assume they are since you note those cyl)

    what you describe sounds like plug arc. Carefully inspect, in lighting condition you can see a small spark/arc in, cyl 1 & 3 around the plug and opti boot end for any sign of arc. If none your opti cap may be cross tracking or FU
    96 BBB 383/T56

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  5. #14
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    Quote Originally Posted by BALLSS View Post
    IDK how old your MSD opti is....but they recently have had a huge rash of issues with their Opti's

    if you are throwing 0301 and 0303 codes cyl 1 & 3 are misfiring (assume they are since you note those cyl)

    what you describe sounds like plug arc. Carefully inspect, in lighting condition you can see a small spark/arc in, cyl 1 & 3 around the plug and opti boot end for any sign of arc. If none your opti cap may be cross tracking or FU
    I dont know if its teh original one I bought, but I first bought it when they first came out, 06 or 07, I cant remember.
    BUT I have sent it to them 2 times, both due to water pump failure.

    when I got to work today, I popped the hood and checked the wires on the plug side and they look fine. not loose at all.

    going home I got a hard misfire P0301
    Freeze Frame
    P0301: Cylinder 1 Misfire Detected (Powertrain, Generic)
    Fuel system status, Fuel system 1: Closed loop (1)
    Fuel system status, Fuel system 2: Closed loop (1)
    Calculated engine load: 5.1 %
    Engine Coolant Temperature: 132 °F
    Short Term Fuel Trim - Bank 1: 4.7 %
    Long Term Fuel Trim - Bank 1: 6.3 %
    Short Term Fuel Trim - Bank 2: -1.6 %
    Long Term Fuel Trim - Bank 2: -3.1 %
    Intake Manifold Absolute Pressure: 8.3 inHg
    Engine RPM: 1161 RPM
    Vehicle Speed Sensor: 20 mph
    Air Flow Rate from Mass Flow Sensor: 1.6 lb/min
    Absolute Throttle Position: 0.0 %
    when I put it in a high gear and give it gas it acts like somebody pulled a plug wire.

    I am going to lift it up tonight if I get a chance and check the connections at the opti, swap in older plug wires and pull the plugs and check the gap.
    97 Trans Am WS6, LT1 factory 4bolt freak, M6,
    68 Firebird 400, YC 400, 670 heads M4
    14 Fiat 500e
    , 83kW motor, 24kWh 364 V battery

  6. #15
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    you would be hard pressed to see any plug/boot arc in daylight. Been there and done that

    before you start swapping parts I would closely look at #1 and #3 plug end. Get the car up on ramps and look from underneath also. If you are using the stock plug wire heat shields....pull them. The arc can be on the "inside" of those heat shields making it just about impossible to see

    a plug arc issue with engine under load (high gear) and heavy pedal will very easily show up as a stumble.

    It may be a Opti issue. My MSD was bad out of box and that was several years ago. Sent it back in for a rebuild and sold it. Never again on their Opti for me. MSD C&R is good
    96 BBB 383/T56

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  8. #16
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    The freeze frame indicated the throttle was closed (0.0%), as confirmed by the very low MAP (8.3"Hg). Unusual time for a misfire, under very little load

    On the other hand, trying to accelerate aggressively at low RPM in 5th or 6th puts the ignition system under high stress. That's the first place you may see misfires. Checking for arcing at idle isn't guaranteed to find the problem, but it's worth the try.

    When looking for the possibility of cross firing, don't forget that the spark may be jumping between plug wires where they run in parallel. Could be damaged wire insulation, could be excessive plug gaps. What do the #1 and #3 gaps look like? Then as mentioned above, there's carbon tracking in the cap, or even breakdown of the dielectric resin in the cap that insulate the thin conductors that criss-cross in the cap to route the spark from the cap buttons to the correct wire tower.
    SOLD - GONE TO A (VERY) GOOD HOME ! - 94 Formula A3+1: 381ci forged stroker - Callies Stealth, Oliver 5.85 billet rods, BME nitrous pistons / CNC LT4 heads / CC solid roller / TH400+GearVendors OD / 4.11 Strange 12-bolt / 300-shot N2O / Spohn Suspension / roll bar / MoTeC M48 Pro engine management system /a few other odds 'n ends.

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  10. #17
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    Quote Originally Posted by BALLSS View Post
    you would be hard pressed to see any plug/boot arc in daylight. Been there and done that

    before you start swapping parts I would closely look at #1 and #3 plug end. Get the car up on ramps and look from underneath also. If you are using the stock plug wire heat shields....pull them. The arc can be on the "inside" of those heat shields making it just about impossible to see

    a plug arc issue with engine under load (high gear) and heavy pedal will very easily show up as a stumble.

    It may be a Opti issue. My MSD was bad out of box and that was several years ago. Sent it back in for a rebuild and sold it. Never again on their Opti for me. MSD C&R is good
    Nah I am using MSD Super Conductor wires with no heat shields.

    Im hoping its just a plug or loose wire at the opti

    MSD has been pretty good customer service-wise for me, the opti has run great previously, just the water pump killed them, which probably would have happened with an OE one.

    Quote Originally Posted by Injuneer View Post
    The freeze frame indicated the throttle was closed (0.0%), as confirmed by the very low MAP (8.3"Hg). Unusual time for a misfire, under very little load

    On the other hand, trying to accelerate aggressively at low RPM in 5th or 6th puts the ignition system under high stress. That's the first place you may see misfires. Checking for arcing at idle isn't guaranteed to find the problem, but it's worth the try.

    When looking for the possibility of cross firing, don't forget that the spark may be jumping between plug wires where they run in parallel. Could be damaged wire insulation, could be excessive plug gaps. What do the #1 and #3 gaps look like? Then as mentioned above, there's carbon tracking in the cap, or even breakdown of the dielectric resin in the cap that insulate the thin conductors that criss-cross in the cap to route the spark from the cap buttons to the correct wire tower.
    After it heats up I can hear the exhaust popping intermittently. I might try to see arcing during a hot idle.

    I am going to double check everything, the last person to touch the car was some mechanic that my dad hired to change the oil pan gasket, when I got it up in the air this weekend to replace the O2s I saw all he did was shoot/rub RTV around the pan...

    Im really hoping that its not the opti/cap
    97 Trans Am WS6, LT1 factory 4bolt freak, M6,
    68 Firebird 400, YC 400, 670 heads M4
    14 Fiat 500e
    , 83kW motor, 24kWh 364 V battery

  11. #18
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    Got the car up in the air last night. 1st thing I did was check all the spark plug wire connections, everything was wired up good, still was misfiring.

    I sprayed down the cables with water to see if it would arc and I did not see anything, it was not completely dark, but Im pretty sure I didnt see anything. In the past when I had a bad wire and I sprayed it you would see the arc pretty clearly

    I pulled plugs 1, 3 and they looked good:
    17060140.jpg
    17060144.jpg
    17060146.jpg

    both were gapped at .045"

    I reinstalled them and made sure they were tight, fired it up and still misfire

    I pulled the plug wire and put an older known good wire on it and still misfire.

    At this point it was really late and I was exhausted so I stopped.

    Im gonna leave work early and check the injector.
    My plan is to:
    1) check the resistance on #1 injector vs the rest
    2) put a noid light and see if I am getting signal if the resistance is good
    3) prime the fuel rail and manually fire the injector and see what the pressure does on #1 vs the rest

    Any other ideas?

    Man I hope its not the opti, I really dont want to dig into the opti
    Last edited by captainofiron; 06-13-2017 at 10:06 AM. Reason: forgot to mention gap
    97 Trans Am WS6, LT1 factory 4bolt freak, M6,
    68 Firebird 400, YC 400, 670 heads M4
    14 Fiat 500e
    , 83kW motor, 24kWh 364 V battery

  12. #19
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    I rented an Autozone pressure gauge, first one was not holding pressure, it shot gas everywhere, thank God I had the vent tube pointed down into a oil catch pan. Got another in exchange, not sure how accurate it is.

    Checked the injectors, they are all measuring 12.5 ohms (+/-0.1)

    Checked the pressure, with key on its reading 32psi (I dont know if that is absolute or not so I will annotate psig), at idle my pressure is about 32psig, with the vacuum off the regulator its ~40psig

    I manually fired the injectors from 38psig and all within 5 seconds were down to about 12psig. All across the board the fuel system seems ok, I replaced the filter to see if that would bring up the pressure. Pulled it out and replaced, no change in rail pressure.

    SO I got under the car again checking for arcs with a test light attached to my battery ground. Running across the wires the leds would very faintly flicker. No flashes

    So I put an inline plug wire test light and found the culprit...

    Here is Cylinder 3 for the control:


    And here is Cylinder 1


    pretty sure there is a problem with the opti... whether its the cap or the opti itself

    Pretty disappointed
    97 Trans Am WS6, LT1 factory 4bolt freak, M6,
    68 Firebird 400, YC 400, 670 heads M4
    14 Fiat 500e
    , 83kW motor, 24kWh 364 V battery

  13. #20
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    Did you check spark on any other cylinders?
    Last edited by Injuneer; 06-13-2017 at 09:17 PM.
    SOLD - GONE TO A (VERY) GOOD HOME ! - 94 Formula A3+1: 381ci forged stroker - Callies Stealth, Oliver 5.85 billet rods, BME nitrous pistons / CNC LT4 heads / CC solid roller / TH400+GearVendors OD / 4.11 Strange 12-bolt / 300-shot N2O / Spohn Suspension / roll bar / MoTeC M48 Pro engine management system /a few other odds 'n ends.

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