: 2001 STS P0307. Stalls and hesitates under light acceleration



butlerj90
08-23-10, 09:12 PM
Hi, I'm trying to diagnose a cylinder 7 misfire on my friend's STS. The car has 78Kmiles and has a P0307 code. Also, intermittently the car hesitates and then stalls under light acceleration. If anyone has any experience with this any help would be greatly appreciated. Unfortunately I don't have very much experience with Cadillacs as I am a Lexus technician and I drive Chevys with gen1 small blocks . At first I was thinking ignition coil, but I quickly found out that you can not simply swap coils on these engines. Local Caddy dealer said spark plugs on these cars aren't needed until 100K. I'm just trying to help a friend out as much as possible.

Thanks for any info,

Jason

Ranger
08-23-10, 09:29 PM
You can't swap coils, but you can swap coil cassettes. Get one from a junk yard and try it or swap right to left bank and see if the misfire follows.

Have you used a noid light or a stethoscope to check to see if the injectors are pulsing?

No other DTC's? How did you check them? Try using the onboard diagnostics if you didn't. The instructions are in the sticky at the top of the forum page.

butlerj90
08-24-10, 02:32 AM
You can't swap coils, but you can swap coil cassettes. Get one from a junk yard and try it or swap right to left bank and see if the misfire follows.

Have you used a noid light or a stethoscope to check to see if the injectors are pulsing?

No other DTC's? How did you check them? Try using the onboard diagnostics if you didn't. The instructions are in the sticky at the top of the forum page.

Haven't tried a noid light yet but I'll try it today after work. I checked for DTC's with my OBDII scanner and P0307 was the only code I got. I figured since the car is a 2001 any DTC's would show up on the scanner but I'll the onboard diagnostics as well.

Thanks.