P400 generic misfire, plus dash tach, speedo and trn sinals

[sempar]

HI,

Started having a bad misfire when at full temp a couple of days ago. Car runs fine when cold and also in closed loop, but after the car sits for a while hot, it misfires on one bank....feels like intermittent misfire on all the plugs on that bank. code reader only shows "generic misfire", no clue as to what bank or cylinders. I've had to replace the coil packs before,both front and back, and code reader always show the bad cylinders. Not this time. Started it up today when hot , car misfires and I lost the tach, speedo, odometer, and turn signals; 4 way flashers, high beam and brake lights along with all other accessories are working fine. I'm thinking that there is a crack one or the other banks coil driver board. Car gets hot, crack widens, driver board doesn't fire the coils. It looks like the driver boards are replaceable, but trying to get the rear coil pack is a bear now that I'm a "little " bit older.

Anyone run into this before?

John

[Paulaurora]

random misfire most likely issue with Ignition modules the best thing to change 2 since if one failed today 2nd will be very soon as well. Is your car V6 or V8? what year?
this is for v 8 www.amazon.com/Ignition-2000-2003-Cadillac-Oldsmobile-Compatible/dp/B01FSWO4WO/ref=asc_df_B01FSWO4WO/?tag=hyprod-20&linkCode=df0&hvadid=693607260953&hvpos=&hvnetw=g&hvrand=18367611387340624846&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9009920&hvtargid=pla-783749500202&psc=1&mcid=74a541c503e03f7aadc89ce50ddbe0a8&gad_source=1

[sempar]

HI Paul,

Turns out that the new Delphi front coil pack I replaced about a year and a half ago has went as well. New coil pack installed and now runs smoothly. Unfortunately, still have no tach, turn signals, speedo, or odometer. MIL is out as well. I'm thinking that the Instrument Panel Cluster has lost the serial data from the PCM. So far, connectors look good, only other one to check is the connector at the back of the IPC. Have a place up here in Canada that repairs these clusters, so when I take the cluster out I'll check that connector before shipping it out. Ugh....

John

[sempar]

Oops forgot... 2001 V8.

John

[Paulaurora]

Jun 23, 2024 20:58:25 GMT -6 sempar said:

HI Paul,

Turns out that the new Delphi front coil pack I replaced about a year and a half ago has went as well. New coil pack installed and now runs smoothly. Unfortunately, still have no tach, turn signals, speedo, or odometer. MIL is out as well. I'm thinking that the Instrument Panel Cluster has lost the serial data from the PCM. So far, connectors look good, only other one to check is the connector at the back of the IPC. Have a place up here in Canada that repairs these clusters, so when I take the cluster out I'll check that connector before shipping it out. Ugh....

John

Check fuses. Its not something common for speedo to die . To be honest i saw lights go out or led for check engine light being broken but never saw speedometer stopped working fully. I think its blown fuse or something try to take out the radio and see if speedometer will come up. since radio does talks to it as well for speed sensor and if there is a short it can cause an issue.

[skorpiius]

Jun 23, 2024 20:58:25 GMT -6 sempar said:

Have a place up here in Canada that repairs these clusters, so when I take the cluster out I'll check that connector before shipping it out. Ugh....

Where are you going to send it? I'm also in Canada and the local place I emailed a few days ago hasn't responded yet so I may need an alternative.