ODB II codes

[framda]

My 98 GT developed an intermittent engine miss four days ago. No check engine light. It is most noticeble while maintaining about 50mph. I do have a little bit of timing chain noise mentioned in another thread but I don't think there is enough chain slack to cause an engine miss. Some times it is barely noticeable and sometimes it is pretty bad. I went to Autozone and bought plugs and wires. (I bought this car three months ago and haven't tuned it up yet.) The asshole at Autozone gave me attitude the minute I asked him to check my codes. He said that the scanner was broken, the manager told him to pull one off of the shelf. He said couldn't find the connector, I showed him where it was. He said that his scanner would only show codes if the check engine light was on. I told him that I have spent over $4000 in that store over the past 5 years and if he wanted to see another one that he would hook my car up and check it for me. Well finally he figured it would be easier and quicker to hook the damn thing up. after about 30 seconds he said "yep just like I said no codes." I wrote service at a Ford dealer after I quit wrenching Chrysler's shit boxes and I had many techs pull codes for me. From my (faded) memory Some codes are hard and some soft with only the hard ones triggering the check engine light. Either way I need to tune the car to see if that cures it but whats up with the codes anyway?

 

[Willis_98GT]

When you change the plugs and wires examine everything deeply.. sometimes coolant likes to leak threw the intake mainfold into the spark plug valleys, about 80% of the ignition problems in these cars are because of that. check vacuum lines also, when those become brittle and start letting unmetered air threw it will goof up idle/drivability.

 

[JerZeyStangz]

I need to check my brittle vaccuum hoses because they've been on the car a long time.

 

[joekd]

Codes will only show if pending (ready to set off CEL) or if the light is already on

This is why I bought myself a code reader, no dealing with a-holes who are too lazy to take the 1 minute to help

 

[framda]

I didn't think about the coolant leaks, definately something to keep in mind, thanks! I took a closer look today and found a couple of dry vac lines. The worst was the one that runs to the thermister valve for the evap cannister. I have been smelling a faint odor of gas every once in a while but couldn't track it down. I have heard this mentioned before along with the cannister as being likely so I am going to go through all of the vac lines after I change the plugs and wires. I am going to pick up a fuel filter as well but do all of this in stages and check in between so I can figure out what it was causing it in case it continues or comes back.

As far as the ODB II, I have seen the interface cables to hook up to a laptop. Is this just for custom tuning or can you check and clear codes also?

Thanks for your help. Fred

 

[Willis_98GT]

I didn't think about the coolant leaks, definately something to keep in mind, thanks! I took a closer look today and found a couple of dry vac lines. The worst was the one that runs to the thermister valve for the evap cannister. I have been smelling a faint odor of gas every once in a while but couldn't track it down. I have heard this mentioned before along with the cannister as being likely so I am going to go through all of the vac lines after I change the plugs and wires. I am going to pick up a fuel filter as well but do all of this in stages and check in between so I can figure out what it was causing it in case it continues or comes back.

As far as the ODB II, I have seen the interface cables to hook up to a laptop. Is this just for custom tuning or can you check and clear codes also?

Thanks for your help. Fred

Their is a cel for the evap cannister, it will come on my car from time to time, i replaced it with the purge valve solonoid a while back and it went away

 

[framda]

Cured!

Ok changed out the vac lines first, pulled the pass wheel well liner and changed all of the lines for the evap cannister, changed PVC lines, Still had the same "miss". R&R the plugs and wires, bingo that was it smooth as butter now. @Willis_98G, Thanks for the tip on coolant leaks, mine were all dry but I did find a lot of staining from where the previous owner had a coolant leak that he told me about. Fred