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fredmeister fredmeister is offline
Smart quod bastardus
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Join Date: Oct 2002
Location: Baltimore, MD, USA
Posts: 2,235
need help with engine misfire

I installed an MSD 6AL2 programmable ignition and am having a terrible misfire after the engine has started.

The rotor is the NAPA non resistor rotor and brand new cap. Wires are stock OEM braidied wires and the plugs were gapped at 0.040.

I am able to start the car and it runs fine for the first 1 minute or two then it starts to stumble and misfire. As soon as I touch the gas peddle to rev it up the engine starts to backfire and stall. AF ratio is bouncing all over the place going lean then rich as this is happening.

My max timing was set at 32 degrees BTDC and I have programmed the retards to take out timing to exactly simulate the stock 79 turbo timing curves from the manual. Idle timing is 2 degrees BTDC at 950 rpm.

I have replaced the front fuel pump and all the relays thinking it migh be fuel related. Front pump was making some noise so I installed a Bosch 044 front pump and rewired the fuses to break up the circuit to each relay. --No change.

Fuel pressures are 3.5bar warm CP and SP is 6.4bar all within spec.

I have read on the MSD forums about rotor phasing thinking this might be the cause, but am not sure if I am barking up the wrong tree here.
HAS ANYONE HAD ISSUES WITH ROTOR PHASING WHEN USING THE MSD 6AL2 UNIT? Is this what it sounds like, as I am running out of hair to pull out of my head and need to get this thing running.

Any help is greatly appreciated from you guys this has me stumped now.

1979 930 Turbo....3.4L, 7.5to1 comp, SC cams, B&B intercooler, Snow Perf water/meth injection, Rarlyl8 headers, Garret GTX turbo, 36mm ported intakes, Innovate Auxbox/LM-1, custom Manually Adjustable wastegate housing (0.8-1.1bar),--running 0.7bar max
---"When you're racing it's life! Anything else either before or after, is just waiting"
Old 05-19-2013, 01:40 AM
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