C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

1985 "Skipping" on acceleration

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Old Feb 4, 2013 | 11:40 AM
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Default 1985 "Skipping" on acceleration

On acceleration my 85 will skip/stumble a lot. Once at highway speed it clears up and the car runs good. I have new plugs. The mass airflow sensor is good. What could be causing this? It appears to get worse as the car is driven more and more (or when it gets up to optimum operating temperature). It actually runs very much like there is a fouled plug (but there is not).
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Old Feb 4, 2013 | 12:01 PM
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read the flash codes. test fuel pressure, ohms test the injectors. Without ANY of that info, you can only GUESS.
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Old Feb 4, 2013 | 12:04 PM
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No codes. Will check fuel pressure. But, it runs good at times (most times) just stumbles on acceleration (sometimes badly) then clears up and runs great.
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Old Feb 4, 2013 | 12:45 PM
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When was the last time the cap and rotor were replaced?

Last time the inline fuel filter was replaced?

How old are plug wires? When it is dark out, open hood and start car and look for any wires that are arcing.

Check fuel pressure and ohm injectors.
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Old Feb 4, 2013 | 12:59 PM
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Originally Posted by John A. Marker
When was the last time the cap and rotor were replaced?

Last time the inline fuel filter was replaced?

How old are plug wires? When it is dark out, open hood and start car and look for any wires that are arcing.

Check fuel pressure and ohm injectors.
Complete the tuneup and change the cap, rotor, wires, possibly the ignition module.
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Old Feb 4, 2013 | 01:33 PM
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Thanks for all the replies/suggestions. I will look into all of this. I guess I am confused by all this since I always thought electrical issues were either yes or no. This intermittent issue was leading me to something other than something like a rotor or ignition module. I just cheked the fuel pressure and it in within specs.
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Old Feb 12, 2013 | 07:46 AM
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FYI ..... Problem solved. Changed the ignition module and the pick-up coli and all seems well. The cars has been running good since these were replaced. From looking at the part, I think the pick-up coli was actually the problem. It had become heated and a lot of the "glue" from the coils had dripped down into the distributor just below it.
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