Cadillac CTS First Generation Forum - 2003 - 2007 Discussion, 2.8 Rough Idle in Cadillac CTS Coupe, Sport Sedan and Sport Wagon Forums; hey guys been searching the forums and have gotten good tips.. but need more. so chime in with any solutions ...
- 07-18-13 04:23 PM #1Cadillac Owners Member
- Automobile(s): Cadillac CTS
- Join Date
- Aug 2007
- Honolulu, HI
2.8 Rough Idle
hey guys been searching the forums and have gotten good tips.. but need more. so chime in with any solutions or possible problems.
had codes P0300, 301, 302, 304, 306. car starts normal on a flat surface but at an angle on my drive way (which is steep) it clunks and clutters for a few min then starts ok.
heres what I've done so far. thought the car was having a issue with the pcv plug being loose or clogged. so cleaned it with compressed air and my replacement is on the way.
I did the swap test with the coils. switching bay 3 coil to bay 2. cleared codes bay 2 ok. spark plugs had some oil on them as well. old plugs were at .60 instead of .44 but thats after 7yrs so thought its time. haha
So I replaced my spark plugs and all igintion coils. heres the fun part bought some NGK irdiums on amazon. codes still appear. and issue with start still occurs as above. so decided to change oil and check the spark plugs as they had oil on them. then the 3 of the NGK plugs brake at the insulator. its so bad some insulation get in the hole where the plugs go. assuming the camshaft.
I know replacing the seals on the camshaft should stop the oil leak. parts on order. now the car cranks at start up but no clank just rough idle even on the flat and when you accelerate its rough. same codes as above after the clear.
- 07-21-13 05:04 AM #2
Re: 2.8 Rough Idle
So ran car and seems to be running a little better. Cleared codes and no CEL. I've lost some power and getting weird acceleration. At 40 mph it stays at 4k rpm for 3-5 seconds before hitting the next gear. Only if I push it to the floor I get a jump but no smooth acceleration. I have an after market 5zigen dual exhaust. Before I changed my plugs I didn't have this issue. The plugs I have now are Bosch. I'm thinking could be a transmission issue or something with my ECM needing to be tuned.
Any input would help!! Thanks