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94 PCM Upgrade Gone Awry

177 Views 0 Replies 1 Participant Last post by  DonLTx78641
I recently upgraded from a 93 ECM to a 94 PCM for tuning purposes. The harness was redone for sequential injection. Wire by wire conversion for 94 PCM connectors. First start was completely painless. Smooth Idle, initial 1100 RPM dropping to approximately 800. Closed Loop (unheated) in 3.5 minutes. Engine sounded smooth and crisp. Never should have taken it on the road.
All went well up to about 3000 RPM under load. Missing violently. More pedal resulted in worse run conditions. Flooring it really bad. From stop until 2500-3000 smooth. With slight acceleration beyond 3000, okay until about 75% throttle. Bad results.
Code 42 Set. Checked all wiring associated with ignition. No shorts, grounds, or opens. Replaced ICM with 93. No change at idle or on the road. Reinstalled 94 ICM. No change. Found no reason to change Coil other than problem was with load. New coil, no change. Checked All Ignition related wiring from PCM to components. No obvious problems. Opti Test Connector checks good. Cannot check to Opti.
No Code 36 or 16 flashed by or set. I assume the Low Res signal is good as well as High Res. Tach was working and engine was running. Tried disconnecting the Tach Wire (White) from Black Connector on Coil (Term. A) and connecting Tach to A13 (Red) Tach Output. Tach reads 425 and Engine Will Not idle above 450. Reconnected to Coil. Engine Idles at 450 and will not increase.
I loaded up eeHack and finally figured out enough to get some graphs. Unfortunately I downloaded Flashhack. Now I can't get to eeHack as it no longer connects. I have Uninstalled and downloaded twice. Cannot get past the Connect Button as the program is unresponsive.
Sorry for the long winded post.
Anybody had this happen? I need some outside help.
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