98 GT Multiple ODB Codes

Idle air bypass

or some of the coils went bad, plugs will tell

dosen't sound right, should change the wires out, use the si grease. If the fit was bad, (coil to wire) change out the plugs too. make sure you "read" them as you take them out.

O2 sensors?

there is a can for fuel vapors from gas tank on the vacuum system, sometimes the hose comes off. replace if loose or cracked

Interesting... my '97 has been making some odd noises with a light power loss. While driving around trying to figure out what it was it was becoming less and less intermittent. Idles perfectly does it only under acceleration load. Eventually the MIL came on. Just read the codes a few minutes ago, misfire, cylinder #8... the fun begins tomorrow I guess.

This sounds hokey. I would consider the wires and coils suspect.

O2 sensor(s) may be an issue, maybe they aren't quite dead yet... or you still have a misfire and it's sending raw hydrocarbon out the exhaust. This would get the pre cat O2 sensors to declare the engine too rich and as the computer tries to compensate it runs worse but still pumps HC into the exhaust.

I am bit rusty here, but wouldn't an air leak lead to a lean condition?

Can you reinstall your original wires and coils? Since they were good when you pulled them, it would help eliminate some prime suspects.

I thought I would add some new information and maybe clear up somethings.

The wires to the Screamin Demon coil are Ford wires.

It was many months since the installation of the coils and wires since the problem started.

I noticed at first that when I started the car (cold) and then backed it out of the garage, there were large idle swings. I kept telling the original mechanic to clean the IAC. He kept saying what is it with you and the IAC? So he would fool with something and it would run better.

After the first mechanic left, I started having idle problems again. The second mechanic noticed that the wires seemed to be not completely connected to the coil. When he fooled with this the idle improved. That is why I think they thought of the wire problem in the first place.

Then after continuing to have idle problem, I finally got a code.

Thats when we got the Misfire on Cylinder #8 code.

This is were the third mechanic comes in.

I was recovering from a fractured wrist and could not open my hood. Since I just stopped by to get the code read he did not have time to really work on my car, he put a wire tie at the coil for the wire going to Cylinder #8. He then cleared the code.

Things were definitely better. My wrist was getting stronger so I planned to complete the wire tie job. One day before I was going to fix this i got a code.

Since I was pissed, I did the remainder of the wire tie job. There was also no question that the clamps to the coil were not making good contact. I also disconnected the battery for a 1/2 hour to let the computer reset.

Everything was fine and then I got a code. I was also driving with the top down and when I stopped the exhaust smelled really bad. Not sulfur, but a mixture of unburned fuel and something else that I have no idea what it was. Even though I have worked in laboratories and have smelled some things that would take your breath away I could not figure out the smell.

I was confused when I wrote the original post because he did not give me printout from the code, I did not read it correctly and I was going on memory. He gave me a copy off the Alldata print yesterday.

So... The New code is P0175 Fuel/Air Ratio Rich Bank 2.

He told me that he did a history scan and there were no more instances of the Cylinder #8 misfire.

If I am correct, isn't Cylinder #8 on Bank 1? The new code says Bank 2.

A lot of items on the printout relate to blocked airflow. He took off my K&N and it looked good and checked several vacuum lines. No signs of wear. He is going to research some things. He might try to ask his buddies if they can pull the code diagnostic chart off the Ford Database. He was really impressed with how quickly I got a response on this Newsgroup. Being young he has no concept of Newsgroups.

Yesterday other than a short idle problem after I started the car, the car was running great. When I saw the mechanic yesterday, He said that it sounds like it is running sooth. Two hours latter, five minutes from home, it stalled at a light and there was that smell again.

Here is my weekend plan.

I am going to try to pull a few plugs to see how they look. Problem is that I don't know if I will be able to get to them all. Some of them seem impossible to get to.

Get a can of Carburetor Cleaner and clean the IAC.

He said to try to spray some of the cleaner around the plugs to see if the engines really improves.

Maybe I should just get a new set of plugs. Any suggestions?

As always, the reason you write here is for advice. All is appreciated.

There are 66,000 miles on the car. I don't jump on it at lights unless some kid and his toy with the fake muffler wants to go. Then two weeks ago I was just puttering along and at two lights in a row Some guy in a Monte Carlo floored it. I realized he had his girl with him. Just happened to pull up next to him again at the next light. I knew the timing of that light really well and I gave him three gears worth of embarrassment then backed off. He continued to floor it changing lanes ahead...you name it. What an idiot.

I have only had it passed 100 less than 10 times since it was new. Never exceeded redline.

Thanks for all your help about this already and in the past.

Sorry for the long post.

Regards,

Bill P.

PS When I was going to buy the Stang I was debating whether to get a stick or auto. I got a lot of responses here. But one women's answer was so great that I got the stick. Never regretted it for a minute. That plus getting the convertible.

Not sure, but as I follow my shop manual, number 8 is at the firewall on the driver's side.

At least pull number 8 to see if there is anything going on with it.

I dried out the plug wells on mine as best I could tiny bit of liquid left in each of the three. started it up today, pulled it out of the garage, problem noise seemed to be gone. I let it idle outside to warm up as I watched for coolant leakage... didn't see anything.

Decided to take it out... instantly I feel/hear the problem but very slight, less than before... I stop the car and shut it down. I pull the boots off.. each is wet inside.. less fluid in the wells than before I put the boots back on, but the boots which I had dried inside are now wet. Steam rises from the three holes. Seems what little water was left is making a path to ground.

I decide to put the boots back on and put the car back in the garage. I put them back on, problem isn't there. Put it in the garage, pull the boots off, dry them, watch the steam come out of the wells and decided to just let it sit and boil off the remaining fluid as the engine cools and decide that I am going to have to pull the plugs out and see what the other side looks like. Going to buy new plugs and wires. It was on my to-do list anyway since they are closing in on replacement time. But even if the plugs/wires are worn there is still the fluid.

I am just hoping that it's been seepage over a long period of time or perhaps runoff from cleaning the engine and replacing the radiator hoses. (The color due more to 'simple green' than coolant? Although that cleaning was a couple months back. What I am affraid of is that the coolant passage near #8 is leaking through the intake manifold seal into #8. Although the coolant/water on the outside around the plugs causing ignition issues is 100% consistant with the symptoms. I would think coolant seeping into a cylinder would cause a much clearer shake rather than what amounts to a slight noise and even slighter vibration. No sign of coolant/oil getting into each other's areas either. Still going to take it careful though.