My car is running rough like one of the cylinders is not firing, but I'm not getting any sort of diagnostic code. The one time you want one of these freakin codes, you don't get one!

Any ideas? My car has been pinging slightly, but I filled up at a different station this week so I don't think it's bad gas.

It seems like if I had a clogged fuel filter or bad plug, I would get some sort of lean or rich code.

 

maybe a TPs sensor or a fuel filter. my sisters mustang had a problem like that.. it was the tps

 

Check your plug wires. I had the same problem and found one of my wires was badly corroded.

 

Maybe a vacuum line got disconnected.

 

It finally threw a code....P2197 which explains the pinging Iv'e heard lately. I guess this is some sort of lean condition code. I'll have to research it but any ideas would be appreciated.

Thanks.

 

here is something i found on the net...
TSB 04-17-4: MIL Lamp On, Lean DTCs – 2000-’02 Escort and Contour If you find any lean DTCs on one of these vehicles, Ford says the cause may be an engine vacuum leak, possibly around the PCV valve or in the PCV vacuum plumbing. Such a leak may set the following DTCs: P0171, P0174, P1130, P1131, P1150, P1151, P2195 or P2197. The codes may indicate a lean fuel condition or a lack of heated oxygen sensor (HEGO) switching. Ford says not to replace the oxygen sensor, MAF sensor or PCM because the cause may only be a vacuum leak or an incorrect sized PCV valve that flows too much air.
To check for a possible vacuum leak, use your scan tool to look at long-term fuel trim (LONGFT) and short-term fuel trim (SHRTFT). With the engine warm and idling, add the long-term and short-term fuel trim numbers together. If the total correction is greater than plus 20% at idle, it probably indicates a vacuum leak that is making the fuel mixture run lean. To confirm the leak, rev the engine to 2,500 rpm and hold. Again, note the LONGFT and SHRTFT numbers. Add the numbers together. If the total correction at 2,500 rpm drops 15% or more, it confirms a vacuum leak at idle.
To find the vacuum leak, try pinching off individual vacuum hoses one by one while watching the SHRTFT number on your scan tool. When the SHRTFT number drops, you’ve found the leak. If no hose leaks are found, the problem may be a leaky intake manifold gasket. Try feeding propane around the gasket. When the SHRTFT correction drops, you’ve found the leak.
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Hmm.........could be. The idle is rough and wants to fluctuate, but it also seems to be missing on a cylinder.

 

how can you tell a cylinder is missing?