I was riding along today the car was running fine and all of a sudden a terrible miss. It was so bad I almost couldnt get off the road, it felt like it was running on 2 or 3 cylinders. I open the hood and find nothing obvious. I start it back up and the engine is shaking like crazy obviously missing on several cylinders or getting no fuel. So as I try to think of the closest tow truck the engine smoothes out and the miss is gone. I drive it home without skipping a beat. What the heck could cause something that bad then clear up and run fine.

Thanks, Tim

 

Check for corrosion on the plug wire terminals, coil wire terminal, and the two Opti harness connectors.

Scan it. Whatever caused the problem may have set a code, and the code would still be stored.

Check the fuel pressure. When was the fuel filter changed last?

 

I checked the fuel pressure it seems fine, 43psi with just the key on and 41psi idleing. The fuel filter was changed about 5000 miles ago. I checked for codes and found 42 and 48. I am just not sure if the codes caused the miss or the miss caused the codes. After i cleared the codes they have not came back. I did put a new msd coil and wires on about 2 weeks ago. I checked them and everything seems fine.
The car is running fine now. I am afraid to drive it though. Any Ideas

 

Use a multimeter to check your wires. How old r your O2's?

 

DTC 42 = a short/ground in the IC Module dircuit

DTC 48 = a fault in the MAF sensor circuit

A "miss" can't cause a short or faulty circuit. A short or faulty circuit can cause a miss.

 

Any ideas what would suddenly cause it to throw 2 codes like that? Now that it is running ok there is no codes.
Thanks,

 

Today the car just dies while idleing, no warning or missing it was like you turned off the key. At first it wouldnt start back. So I checked the coil for spark, it seemed fine. So i go to the plug wires to check for spark. Well the car starts right up. While its running I notice the coil wire is arcing pretty bad against the water pump. There was a small rip in the top of the boot. Could this have caused the bad miss, no starting, and throwing the codes? Or should I keep searching for the problem?