Engine 93 Mustang GT, Code 41/91, KOER Cylinder ID shows 6 and not 8

I sprayed air intake cleaner around my TPS and noticed a very slight change in the idle ( i had to spray directly at the base of the TPS and a couple of seconds later the idle would change), so i put some silicone around it as a "test" and drove it to work today to see if that does anything. Really don't have the money to buy a whole new TB, so if this does end up fixing the issue, then im going to look into trying to disassemble the TB and replacing any O-rings on the throttle blade shaft that could be leaking.

I will probably drop the tank this week when its not a full tank and take a look, 1) to make sure no lines are broken, but 2) i noticed today that my car used to suck in air when i would take the gas cap off after its been run, but the last 3 times now it has no longer done that. Which is kind of an odd thing to notice, but now im wondering where its getting it air from thats keeping it from doing that anymore.

was going to try the slipped gasket test but ran out of time, so im going to try that tomorrow before i go to work or when i get home and see if the cars trying to pull air from the lifter valley

drove the car home last night and no lights on, it was glorious!

Today i went to work earlier then normal, stopped to get food and left about 20 minutes later, and probably about 3 minutes into the drive my check engine light came on again. Im going to pull codes when i get home, really hoping its the code 33 and not 41/91 anymore.

79MercCapri93 said:

drove the car home last night and no lights on, it was glorious!

Today i went to work earlier then normal, stopped to get food and left about 20 minutes later, and probably about 3 minutes into the drive my check engine light came on again. Im going to pull codes when i get home, really hoping its the code 33 and not 41/91 anymore.

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Was able to jump out from work for a second to pull codes, came back with 33 (expected from the EGR delete), 41, 91, and 96 (which 96 may be from shutting off the car and just turning the key forward to right before on, while i coasted to the gate for work.

General karthief said:

This is a long shot, actually two.
seems to me that the lean condition is happening during the cruise mode (?) And maybe you need to inspect the vacuum line from the purge solenoid to the fuel tank. This may involve dropping the tank. Also on another stang I worked on had a problem with the air idle control valve hanging open, but this effected the idle on that car too.
I will also mention that a deteriorating lower intake gasket was a problem on my car, I have had my intake off soooo many times in the past that I could do it in my sleep, and likely the reason I call it the exxon valdez because the last time I didn't get the back rail sealed up good and it leaks from there.
Yeah, I was asleep on that one.

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im going to take a look at the fuel lines either tomorrow morning or this sunday after i get back from the car show out here in Ocean City. If i end up having to pull the intake im just going to put the explorer intake in that i have. No reason to pull the intake to put the same thing back in when i have another sitting here that ive been wanting to put in but have not had a chance to.

Window said:

any happy ending here? genuinely curious because i chased the same issue for a while lol.

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Still troubleshooting! Just got back from Ocean City on Sunday and did not have time to mess with the car. I bought a new O2 harness that im going to put on, but am also going to drop the tank and check the fuel lines as well as taking a look at the IAC. Just been waiting to not have a full tank of gas in the car so I dont make a mess haha

I am also thinking of trying my stock MAF, or swap meters from my stock mass air and put the meter on my 94-95 and see if that corrects the issue as well

Window said:

Do the harness 1st and dont forget to pin the extra plug that comes with it, it's different for each year or something like that. Careful cause u can damage the ecu if u forget it. My money is on the harness fixing it cause that's what worked for me. I had the same 41/91 only hitting the cel after like 10 mins of operation.

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I am hoping it fixes it, I reached out to LMR because the harness i purchased says its for 91-93 but it came with a plastic piece inside one of the pins on the main harness connection going to one of the 02's?