Hey Everyone,
First off wanted to introduce myself and the car. I have always owned imports of some type and I am not too familiar with American cars but lately it seems I am learning pretty quickly with the latest problem I have.
The car is a 2000 v6 auto vert. Car has high miles (170 k) but has run great up until a 2 weeks ago. I purchased the car for my girlfriend a month ago and while my car is in the shop I have been driving it around. I was greatly impressed how great the car drove and ran for the high miles (all highway miles) but attributed it to all highway miles that kept the car feeling new.
This past weekend I noticed a misfire under 2500 rpms. It was slightly noticeable on idle with a minor vibration but under load it felt like I was driving down a slightly bumpy road at 1500 rpms. The car would smooth out just fine on interstate speeds. I decided to do the regular items and replaced the plugs. Soon after I replaced he plugs I had a check engine light on which ultimately read misfire in cylinder number one. I went ahead and bought new wires, coil, and another plug for that cylinder. I reset the code myself and it has come back on since.
This miss was just as bad if not worse and brought it to a mechanic friend of mine. He is ASE certified and is one of the most competent mechanic I know. He ended up putting it on a diagnostic machine. There were no stored codes, showed all injectors were working as well as all sensors. If we powered breaked the car to 1500 rpm's you could feel the car and engine shake right before the tires would brake loose. He said the issue only really happened under load. He checked the O2 sensors under load and he said that BANK one sensor two was running very rich during the miss.
Now if we let the car cool down it would not do it for the first minute or two but would combine shortly after. He decided he felt it could be three other things. Bad driver in the PCM, Low compression in that cylinder or a leaky injector for that cylinder. He used a testlight on the new coil while the car was running to determine that it was in fact cylinder number one causing the issue.
I did a quick compression test on that cylinder earlier today. I did it with the rest of the plugs in using a plunger style adapter (my two screw on adapters did not fit) Knowing that the plunger types read low I was still happy with the 120 psi reading I got. I still need to do another cylinder to compare but that number does not seem to be low enough to be the cause of the misfire.
Also the car does not put out any white smoke and even though their is black soot on the tailpipe you can only get a very small amount of black smoke to come out when the car is repeatedly floored. When I pulled the plug out to do the test I examined the plug and it had some wet substance on it but very heavily smelled of gasoline.
I am hoping it is a leaky injector that is stuck open but in order to swap it I would need to pull off the intake manifold which does not seem like alot of fun. Any ideas or thoughts would be greatly appreciated!
Thanks
Steve
First off wanted to introduce myself and the car. I have always owned imports of some type and I am not too familiar with American cars but lately it seems I am learning pretty quickly with the latest problem I have.
The car is a 2000 v6 auto vert. Car has high miles (170 k) but has run great up until a 2 weeks ago. I purchased the car for my girlfriend a month ago and while my car is in the shop I have been driving it around. I was greatly impressed how great the car drove and ran for the high miles (all highway miles) but attributed it to all highway miles that kept the car feeling new.
This past weekend I noticed a misfire under 2500 rpms. It was slightly noticeable on idle with a minor vibration but under load it felt like I was driving down a slightly bumpy road at 1500 rpms. The car would smooth out just fine on interstate speeds. I decided to do the regular items and replaced the plugs. Soon after I replaced he plugs I had a check engine light on which ultimately read misfire in cylinder number one. I went ahead and bought new wires, coil, and another plug for that cylinder. I reset the code myself and it has come back on since.
This miss was just as bad if not worse and brought it to a mechanic friend of mine. He is ASE certified and is one of the most competent mechanic I know. He ended up putting it on a diagnostic machine. There were no stored codes, showed all injectors were working as well as all sensors. If we powered breaked the car to 1500 rpm's you could feel the car and engine shake right before the tires would brake loose. He said the issue only really happened under load. He checked the O2 sensors under load and he said that BANK one sensor two was running very rich during the miss.
Now if we let the car cool down it would not do it for the first minute or two but would combine shortly after. He decided he felt it could be three other things. Bad driver in the PCM, Low compression in that cylinder or a leaky injector for that cylinder. He used a testlight on the new coil while the car was running to determine that it was in fact cylinder number one causing the issue.
I did a quick compression test on that cylinder earlier today. I did it with the rest of the plugs in using a plunger style adapter (my two screw on adapters did not fit) Knowing that the plunger types read low I was still happy with the 120 psi reading I got. I still need to do another cylinder to compare but that number does not seem to be low enough to be the cause of the misfire.
Also the car does not put out any white smoke and even though their is black soot on the tailpipe you can only get a very small amount of black smoke to come out when the car is repeatedly floored. When I pulled the plug out to do the test I examined the plug and it had some wet substance on it but very heavily smelled of gasoline.
I am hoping it is a leaky injector that is stuck open but in order to swap it I would need to pull off the intake manifold which does not seem like alot of fun. Any ideas or thoughts would be greatly appreciated!
Thanks
Steve