94cobra69ss396
09-25-2009, 07:34 PM
So I had to drive up to the Bay area to train a customer this week. I left on Wednesday around noon and got to my hotel by 7:30pm. On Thursday I went to my customers and did the training and was back on the road on my way home by about 2pm.
The Cobra had been running great and then about 150 miles from LA the exhaust started to get a little bit louder. Not much, but I noticed the difference. Shortly after a truck pulled out in front of me so I had to brake. Once the truck moved back over I downshifted to 4th and started to accelerate when I noticed that the car was misfiring. I thought that maybe a plug wire had burned through because that has happened a couple times so I pulled off at the next exit and popped the hood. To my surprise all the wires looked fine.
Since I was still about 200 miles or so from my house I decided just to get back on the road and drive it home. The car ran fine under light load and the temp never rose. I kept an eye on it and it made it back without any other problems. It even pulled the Grapevine in 6th with the air on without any trouble or even getting hot.
So today I decided to run a cylinder balance test with my scanner. I was expecting it to come up with one bad cylinder but when the scanner was done with the test it gave me a code 90 which meant all cylinders were contributing equally. :huh: So then I pulled all the plugs and they all looked good. No broken porcelain, no bent ground strap and the electrodes looked good. I also inspected the wires and they all looked good. However, I did pull two apart trying to get them off the plugs. I was getting a little worried now.
Since I couldn't find anything wrong I went and picked up a set of new plugs and installed them. I re-installed the same wires that were on the car already with the exception of the two I broke in which case I made two new ones. I then removed the catted H-pipe thinking that maybe the one of the cats broke inside and was causing back pressure and installed my offroad X-pipe.
I'm not sure what fixed the problem but the misfire is gone and the Cobra is running great again. :D
The Cobra had been running great and then about 150 miles from LA the exhaust started to get a little bit louder. Not much, but I noticed the difference. Shortly after a truck pulled out in front of me so I had to brake. Once the truck moved back over I downshifted to 4th and started to accelerate when I noticed that the car was misfiring. I thought that maybe a plug wire had burned through because that has happened a couple times so I pulled off at the next exit and popped the hood. To my surprise all the wires looked fine.
Since I was still about 200 miles or so from my house I decided just to get back on the road and drive it home. The car ran fine under light load and the temp never rose. I kept an eye on it and it made it back without any other problems. It even pulled the Grapevine in 6th with the air on without any trouble or even getting hot.
So today I decided to run a cylinder balance test with my scanner. I was expecting it to come up with one bad cylinder but when the scanner was done with the test it gave me a code 90 which meant all cylinders were contributing equally. :huh: So then I pulled all the plugs and they all looked good. No broken porcelain, no bent ground strap and the electrodes looked good. I also inspected the wires and they all looked good. However, I did pull two apart trying to get them off the plugs. I was getting a little worried now.
Since I couldn't find anything wrong I went and picked up a set of new plugs and installed them. I re-installed the same wires that were on the car already with the exception of the two I broke in which case I made two new ones. I then removed the catted H-pipe thinking that maybe the one of the cats broke inside and was causing back pressure and installed my offroad X-pipe.
I'm not sure what fixed the problem but the misfire is gone and the Cobra is running great again. :D