Suspecting i have a MAF Sensor going bad.

Try pressure testing the intake for leaks.
An update:

Tried the other MAF sensor i received in the mail today and for the 15 minutes that had passed by of her running,she seemed to be her old self. I noticed the CC's were changing pretty normal and that the O2's were bouncing around like they should be. Then after a bit more time had passed, the O2's started to go similar back to sort of how they were with the old MAF, but the idle wasn't rough and it didn't sound like it was stumbling. But noticed the CC's went from changing normal to changing slower then would freeze at 120 then change by 2 a few times then freeze again. They they would climb alittle then freeze again, at which she started to idle really rough so shut her off.
Then i swapped the old MAF sensor back to just see if it'd do that again or if it'd act normal. So fired her back up, watched the CC's change like normal for a couple minutes then started seeing them change by less increments again then they started doing the changing by like 4-6 at a time before slowing down to changing by 2 then starting to freeze, then change by a couple after a couple seconds then freeze, then change then freeze. So it would seem that it may be a flaky O2 sensor issue, that i have found now. Since with either MAF after a certain point of getting the O2 sensor really heated up, the CC's are behaving out of the norm.
I'm pretty sure at least the MAF sensor i had got from a member is in fact good, so at least i can rule out a MAF issue.
I also noticed if i bump the gas when the CC's start to stick it seems to briefly get them to move alittle. So it seems like this O2 sensor possibly could be finally showing it's age and going lazy.
I don't know for sure if it's a factory original O2 sensor or an oem replacement as if it was changed out, it'd been by the previous owner.
I do know it is in the factory location with the purple single wire that plugs into the sensor.
Does this sound like an O2 sensor going bad issue to yall?
It sure seems with what i am seeing, that it's pointing to that being the problem.

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Pretty sure that this O2 sensor is really old, it definitely looks like it has had better days. So i am gonna throw a new one in and that should fix the problem.

I am curious why part of the protective cover the porcelain is hidden by looks like it got really hot and looks like it started to melt on the end.
It wasn't like that before the problem showed up.


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Pretty sure that this O2 sensor is really old, it definitely looks like it has had better days. So i am gonna throw a new one in and that should fix the problem.

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If it was still cross counting it's not a problem. I've seen way worse and they still worked. I replaced one in my daily driver at 381000 miles not because it didn't cross count but the heater burned out and caused a malfunction code.
It wasn't cross counting very much anymore and would stop counting after it got upto temp, so that's why i'm gonna replace it.

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It wasn't cross counting very much anymore and would stop counting after it got upto temp, so that's why i'm gonna replace it.

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It won't count either if the a/f is far from 14.7:1. Looks like it was sooty from a rich condition
That was also what i had thought also.
I still think it shouldnt look like this on the one end, it didn't look like that before.


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Replacing the O2 sensor helped part of the issue go away, but still can't drive her very far without her actting up.
Once it gets warmed up the A/F ratio must not be at the 14.7 ratio because the CC's are hanging again.
I can't find any leaks, but something is going on once it switches over from the inital starting up to being warmed up settings. I am running out of things to check and try to cure the gremlin.
It seems like these cars tend to pick one of the worst times to act up for owners of them, no matter how much the owner makes sure to keep their TR in good health.
Beginning to hate not living near a TR guru, probably wouldn't take too long to figure out why and what is making her do what she is doing with someone that knows about everything there is about TR's eyes on her.
I have a couple things left to try and then i'll of pretty well exhausted everything that i can do without signal wave analysing equipment.
Feeling a bit frustrated and wondering if i'm gonna get the gremlin fixed anytime soon.
Maybe the car is trying to tell me something, i'm not sure.
It's just weird that she does start really good and does run, but as soon as you start to drive her a short distance she isn't too happy.
I'm gonna pull each plug again and take pictures of each 1, maybe i'm not seeing something with one of them that could be causing the gremlin or lead me to where the gremlin is coming from.
Gonna kick myself in the butt if it turns out to be something as simple as the spark plugs even though they were still holding proper set gap and weren't looking like they were toast, that are only at most 4 or so months old.

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If i had an adjustable fuel pressure regulator instead of a non-adjustable stock one, i'd give that a try. Although the readings on a pressure gauge were showing proper steady fuel pressures.
But does seem like she's running alittle more rich than usual since the problem started showing up. There were times when sometimes the INT would rise a tad at idle prior to the problem showing up after driving around, but if i touched the gas alittle & let off while stopped at a light they'd go back to 128. But it would go days or longer without doing that and was something that didn't happen very long when it would do that. Unless something is going on in the chip or the ecm itself once she's warmed up and if put under a driving load is causing her to act up even more. I did have a working spare computer to try to see if maybe that has some role in the behavior or not. After i check the plugs going to swap the chips over to another ECM i have on hand to see if she still acts the same or not. I know there's a chance it might not have anything to do with the gremlin, but trying to rule out anything that could possibly be the cause as much as i can without just spending money and throwing different parts at it.
Having just a Scanmaster and having nothing else to monitor some things with does make it harder to troubleshoot a gremlin like i have somewhat on my own. Sometimes i wished i would of bit the bullet a couple years ago when i had a bit of money to of replaced some of the tech on the car to alittle more modern stuff and would of made troubleshooting this ol' girl easier. I'm fairly sure had i replaced some of the things on this car with more modern efficient better tech, vs having a bit of the oem style stuff on her that troubleshooting would been alot easier to do. Some way some how gotta get her figured out sooner than later.

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It's a big help if you list your mods in the signature.
It's one of your tt 5.6 street 91 octane chips eric. The paperwork that had came with the chip had showed 2008 or 2009 date on it, so it's an older chip.

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Fixed the signature to show what's been done, sorry about not having it setup before. Thought i had at one point.
It sure would be nice if you had a wideband sensor to see what your afr numbers are reading when it start acting up . By the looks of that sensor it looks rich to me plus your plugs should show it also . Does your coolant temp numbers look normal on the SM ?
Any chance your bad 02 fouled our plugs? If they are crudded up and not firing well the new 02 will see unburnt 02 and start throwing in extra fuel. Do your BLMs look normal?
Yeah the coolant temps are normal on the scanmaster, no issues with overheating and the fan does kick on properly.
I also wished i could see the air / fuel ratio readings to see what they were doing too.

About to go pull the plugs and see how they look, in alot of ways just hoping it's the plugs.

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I would get an adjustable fuel regulator first. The chip is adjustable, is it set to something other than the default?
I haven't messed with any settings in the chip, i believe it still is default settings. It was running pretty good, had no KR and didn't want to mess something up, so i didn't play around with any settings in the chip.

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What is meant by "OEM" replacement fuel pump? The stock pump was marginal and with the mods made to the engine more fuel is definately needed. Is 91 the best octane you can get in your area?