Well, I was cleaning the MAF on my 2004 to try and improve poor gas mileage and decided to clean the MAF on my son's 97. Mine went off without a hitch and runs great. His however is running very rough after cleaning it. Now to be honest I don't have the T20 with the hole in it so I sprayed it in place.

My question is, do you all think I damaged the sensor with too strong of a spray or do I really need to take the sensor out with the security torx bit to get it cleaned right?

Please give me opinions. I do not want to buy a new MAF if I do not need to but I need this fixed ASAP

 

Well, I replaced the MAF and still runs like crap with no codes. I do not know what else it could be. I ensured it was all put back together right

 

Did you reset the pcm by disconnecting the battery for 15 mins or so?

 

Is it an idle issue? Could be your IAC valve.

 

I did removed the neg terminal of the battery to reset the computer.

After driving a bit it finally threw some codes. P0304 and P0171. Looks like it is number 4 COP. I just found out that it had been idling rough before this and the kid never told me.

 

With the P0171 you also may have a vacuum leak. Check the PCV elbow behind the throttle body. How many miles on what brand spark plugs?

If it's a 97 with cops, I assume it's a 5.4?

 

Yea, what engine ??

 

5.4l I replaced the PCV elbow last year but will check it again. Has about 62k miles on it. I replaced the plugs about a year and a half ago and have replaced the #4 COP like 3 times in the past 8 years, this will be the 4th time. It is the only one that has ever gone bad

 

So you don't know what plugs are in it ?

 

Again - what brand?

 

Yeah, you should always be using motorcraft plugs and cops.

 

They are motorcraft plugs and the DG-508 COPs

This truck was not driven a lot of miles before my son got it. I used to drive it like 2 miles each day just to pick my son up from school, I had a company van I used to take home. I put about 28K miles on it in 8 years. I only replaced the plugs because I figured it was time, not because they were having any problems. I do not remember the part number of the plug, but I got the recommended motorcraft plugs.

The only issues I have had with the truck is the number 4 COP going bad several times and the PVC Elbow.

 

Swap #4 coil w/#1. Reconnect Battery, fire it up. Watch for a CEL again. Once the CEL "blinks" a few times, you have a DTC in the KAM.

NOTE: CEL DOES NOT need to be illuminated to prove a DTC is in the KeepAliveMemory (KAM). Scan again to confirm coil problem. The miss should have followed coil to #1.

 

I have new COPs coming and hopefully will be here today. Like I said this will be the 4th time I replaced the #4 COP, probably due to the condensation problem. Has anyone rigged something up to stop the root cause?

 

Since the heater core lines can leak only intermittently, it's hard to catch them in the act. There's a brass reducer embedded into the return line to protect the heater core on some models w aluminum intakes. Pressures increase on both sides of that when conditions are met. What I'm getting to in short lol, is that the clamp connections can leak back by #4, -only an intermittent leak.

Another problem may exist above your AC accumulator. Check the wire harness as it hangs directly above. Sometimes the harness falls low enough to come in contact and chafe wires. Regardless, just make sure the harness is in good condition there and covered well. A mag field disturbance may exist creating ignition havoc. So, check that as well.