98gs3 Posted September 28, 2007 Share Posted September 28, 2007 Hey guys, I have a 98 GS300 with over 100K, I got a check engine light, Random cylinder misfire and cylinder 5 misfire. The car runs rough, shakes when accelerating, sometimes with a bit more acceleration it will backfire, real loud noise. 3 years ago Lexus replaced a bad fuel injector. Any suggestions what could be wrong now? Quote Link to comment Share on other sites More sharing options...
dcfish Posted September 28, 2007 Share Posted September 28, 2007 Hey guys, I have a 98 GS300 with over 100K, I got a check engine light, Random cylinder misfire and cylinder 5 misfire. The car runs rough, shakes when accelerating, sometimes with a bit more acceleration it will backfire, real loud noise. 3 years ago Lexus replaced a bad fuel injector. Any suggestions what could be wrong now? Injector again :cries: Quote Link to comment Share on other sites More sharing options...
98gs3 Posted September 28, 2007 Author Share Posted September 28, 2007 Is it an injector for sure, should I order one? The codes were: random cyl misfire, cyl 5 misfire, and random cyl misfire again. Quote Link to comment Share on other sites More sharing options...
dcfish Posted September 28, 2007 Share Posted September 28, 2007 Is it an injector for sure, should I order one? The codes were: random cyl misfire, cyl 5 misfire, and random cyl misfire again. Maybe a cracked plug and/or wire is shot. Quote Link to comment Share on other sites More sharing options...
98gs3 Posted September 28, 2007 Author Share Posted September 28, 2007 I nevery replaced the plugs/wires, is it hard (specifically for cylinder 5)? AutoZone told me the wire set comes with only 3 wires, is that normal? What about the coils? Is that something I can check myself? Quote Link to comment Share on other sites More sharing options...
99blkgs Posted September 28, 2007 Share Posted September 28, 2007 you need to replace your plugs all you have to do is remove the throttle body and u can get to all of the spark plugs easily. if you have never done them its about that time Quote Link to comment Share on other sites More sharing options...
98gs3 Posted September 28, 2007 Author Share Posted September 28, 2007 I can't tell you guys the exact mileage on my car, 1.5 years ago my odometer just stoped and showing 79,xxx mileage for the past 1.5 years. So I am sure I am pretty close to 100K. Is doing spark plugs sufficient, or is there wires/coils involved as well? Any recommendation where to get a cheap fuel injector just in case? Quote Link to comment Share on other sites More sharing options...
dcfish Posted September 28, 2007 Share Posted September 28, 2007 I can't tell you guys the exact mileage on my car, 1.5 years ago my odometer just stoped and showing 79,xxx mileage for the past 1.5 years. So I am sure I am pretty close to 100K. Is doing spark plugs sufficient, or is there wires/coils involved as well? Any recommendation where to get a cheap fuel injector just in case? OEM injector only.................Cheap = Failure :cries: Quote Link to comment Share on other sites More sharing options...
98gs3 Posted September 28, 2007 Author Share Posted September 28, 2007 anyone knows a part number on the fuel injector? Quote Link to comment Share on other sites More sharing options...
99blkgs Posted September 29, 2007 Share Posted September 29, 2007 anyone knows a part number on the fuel injector? u only need 3 wires because the rest are coils and yea u definitely need a tuneup at 100k miles, get some ngk plugs and ull be good. Quote Link to comment Share on other sites More sharing options...
JDMSedan Posted September 30, 2007 Share Posted September 30, 2007 I can't tell you guys the exact mileage on my car, 1.5 years ago my odometer just stoped and showing 79,xxx mileage for the past 1.5 years. So I am sure I am pretty close to 100K. Is doing spark plugs sufficient, or is there wires/coils involved as well? Any recommendation where to get a cheap fuel injector just in case? OEM injector only.................Cheap = Failure :cries: I can tell you right now that you are waisting your time and money just "throwing parts" at your car. How do you know there IS actually a problem with the injector? OBDII codes will only give you a direction to look in, it's not a magic road map to every problem that may go wrong with your car. There are a few simple tests you can do if your interested. Quote Link to comment Share on other sites More sharing options...
98gs3 Posted September 30, 2007 Author Share Posted September 30, 2007 I am interested, what do you have in mind? I don't think it's an injector myself. Quote Link to comment Share on other sites More sharing options...
mehullica Posted September 30, 2007 Share Posted September 30, 2007 If you don't have access to a datalist scantool, or don't want to pay for a diagnosis. Take the plug, and coil for another cylinder and swap them with #5. Check the resistance of the #5 wire. See if your misfire moves another cylinder. I have seen many porous heads leaking coolant around the plug #5 shorting it to ground. I have seen some bad coils also, they fire 2 cylinders each and one side fires but the other doesn't. Hopefully you don't have a porous head, since you'll have to replace it to fix the problem. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.