Help...I cant figure out this misfire

[chase6616]

Hello all, Im in a bit of a bind. I have a 97' Disco with 97k on it and its having some misfiring problems. I searched the threads and they all tell me plugs and wires. I changed both out, tested the coilpacks and the injectors, all working fine. I do have a small exhaust leak from the manifold to downpipe connection. Ive read somewhere that an exhaust leak can send a false reading to the front o2 sensor running lean, so naturally it will try and richen things up (hence why its running so rich), that i all understand. I also saw somewhere that with the GEMS ECU if its getting a really rich reading it will purposly misfire to prevent detonation. So my question is, is that all thats wrong with it a blown gasket, or does anyone else have advice to steer me in the right path...

 

[joey]

More info please, you state you have a misfire, how do you know this? Do you hear it, feel it? Are you getting a specific code from the OBDII?

What type of plugs and wires did you use?

 

[chase6616]

Sorry should have been more specific, im getting P1316. The engine performance and gas milage is in the crapper. I pulled a coil pack from a buddys disco 1 that runs fine and it didnt make a difference so I know its good, I also pulled every injector lead to see if one wouldnt effect how it ran and they all did , so I rulled injectors out. Im using a set of carquest 7mm wires and autolite platinum plugs.

 

[joey]

I would recommend Cheap Champion plugs... never put platinums in a D1 only a D2.

Have you tried cleaning the MAF Sensor?

 

[chase6616]

yes I have cleaned the MAS and the stepper motor, I guess I will try out the cheap champion plugs, and just curious why is it not recommended to run platinum plugs?

 

[joey]

The D1 just doesn't run well with them. Remember it is a 1960 Buick 215ci engine. yes they (LR) has upgraded it a lot, but it still runs better on older tech.

 

[chase6616]

thanks a lot, however i do understand that it might run better,but would that cause i misfire. If that doesnt fix the problem, where do you think i should go next, i thought about flushing the motor out, to get rid of the carbon on the exhaust valves, any other suggestions

 

[joey]

If you still have a miss fire with cheap champions, then I would check and/or replace the plug wires, I would also run some good injector cleaner through the gas. Maybe a can of seafoam in the intake vacuum line. Clean the MAF sensor, replace the fuel filter. Replace the air filter if needed.

I would also make sure you are running premium fuel.

 

[chase6616]

I just replaced the wires like 2 wks ago, also this morning i flushed out the motor and ran a can of seafoam through the intake vaccum line and replaced the fuel filter and ran a can of lucas injector cleaner in the gas tank. Its still misfiring, however on a good note i had an oil leak at the pan gasket, so after flushing the motor i dropped the pan to replace it, and there wasnt a single metal shavingl, the pickup was clean and shiny, so at least i kno the engine flush actually did something. Anyone know where i should go now?

 

[joey]

Ok, before we go any further, how are you feeling this missfire, or are you getting a code?

Please describe the issue with as much detail as possible. When it happens, when it started, do you feel it all the time, under hard acceleration or just at idle.... etc...