misfire

I guess further more, does anyone know if the OEM coils go on both SC 3800s and naturally aspirated 3800s? Wondering if GM made 2 different kinds.

Didn't hear back from anyone...ordered the Delco Coil D555 GM 10472401 OEM Factory Part. Hopefully the resistance is back around the 5.6 ohms...

I just looked up a 98 Riviera SC3800 on Rockauto, and these are the Delco coils, E530C, and D576, and Standard Motor products DR39.

The 96 Riviera N/A 3800 lists the same Delco E530C, D555, and Standard Motor Products DR39.

There may not be a difference.

Cool thanks for checking. I just hope they're at 5.6 ohms. Kinda sucks they don't say it in the item description.

Boom! 5.6 ohms on the delcos. An exact fit!

werdstrave wrote:

Boom! 5.6 ohms on the delcos. An exact fit!

I apologize for missing responding a while back.

You did the right thing, measure the coil resistance with a meter to make sure they match and are in fact the SC coils.

As for your original question, I would get junkyard coils from a pick-n-pull before I bought the AZ coils for this application.

oh by the way while you are in there, clean the metal ground plate for the ignition module and check the wiring harness to the module, at the connectors, for weak wires at the crimps... if the copper work-hardens over time for whatever reason then the wires can snap inside the insulation.

Albertj

werdstrave wrote:

I guess further more, does anyone know if the OEM coils go on both SC 3800s and naturally aspirated 3800s? Wondering if GM made 2 different kinds.

Specifically to this point, GM used a different coil for the SC3800 and the NA 3800. BOTH coils physically interchange, but you can tell the diff just by measuring the resistance with a meter (not by looking at the coil).

Hey guys,

Long story short, I seem to be having this problem again (surging, lack of power, rough/high idle at stop). I'd like to test my coils to see if another one went bad. Is it possible to determine if one is bad by just checking the resistance across the posts of a coil? Or do I have to do this spark check described here with an HEI spark tester: http://easyautodiagnostics.com/gm/3.8L/ignition-coil-pack-tests-3

Basically, will 5.6 ohms across the posts mean I have a good coil, and infinite resistance mean I have a dead coil?

Also...I have a P0122 code: TPS signal low. I don't think I have any problem with my TPS but will confirm this in the morning. Could this code be thrown by a bad coil pack?

werdstrave wrote:

Also...I have a P0122 code: TPS signal low. I don't think I have any problem with my TPS but will confirm this in the morning. Could this code be thrown by a bad coil pack?

When did this P0122 appear? A bad TPS will absolutely cause misfires and horrible running conditions.....

The code appeared and then a few engine start ups later the car started choking and misfiring. I'm going to check the electrical integrity of the sensor now using: http://easyautodiagnostics.com/gm/3.8L/how-to-test-the-throttle-position-sensor-4

Check all the grounds!

Just ordered a new Delco TPS. Should be here tomorrow. I tested the middle circuit and voltage was hovering around .5 V and would not climb to 5 V when I depressed the gas pedal as the link above said it should do. I also unplugged the harness to the TPS and the engine ran very similar as when it was plugged into the TPS. Voltage to the TPS was checked and was solid. I hope this fixes my problem. Will report back.