Suspecting i have a MAF Sensor going bad.

Well looks like the plugs are fouled pretty bad, which i figured would be what'd i find upon pulling them.
That's the first time they were ever that bad looking from pulling spark plugs in the past when i'd change them out.
That would definetly make any car run like crap for sure. So gonna throw in new plugs and should make her all better hopefully.

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Yes 91 octane is all the highest i can get here. I had meant the stock one had been replaced by a newer fuel pump that could keep up with the demand, but wasn't a walbro brand pump.

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Make sure your pump can keep up with boost.

and swap out the plugs for some new ones, reset the ECM and see how the car acts
What is your idle fuel pressure supposed to be set at with the TT chip? The stock fuel press. reg as you know has a range of 34 - 40 psi static and may not be a good choice for your combo. What o2 sensor did you buy to replace that one with?

A bad coolant temperature sensor can cause these kinds of problems also and is something a lot of people never suspect,the one screwed into the front of the intake on the drivers side just to the right of the cam sensor.
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I literally have the same exact problem, hopefully this mechanic can figure it out Saturday.
Reset the ECM (unplug orange wire), drive around a while with the car warmed up, and see what the BLM looks like while cruising, and at idle.

The BLM will tell us if the computer is adding or subtracting fuel. Don't worry about cross counts or the INT for now.
What is your idle fuel pressure supposed to be set at with the TT chip? The stock fuel press. reg as you know has a range of 34 - 40 psi static and may not be a good choice for your combo. What o2 sensor did you buy to replace that one with?

A bad coolant temperature sensor can cause these kinds of problems also and is something a lot of people never suspect,the one screwed into the front of the intake on the drivers side just to the right of the cam sensor.
I am seeing 38psi on the fuel pressure gauge with vac line hooked up and Key On Engine Off, which is the ideal setting for these cars. It at idle running is 36-38 psi fuel pressure, so i know i am good there. It also holds pressure for a very long while without leaking down after shutting her off, so i am fairly sure i am good on that also.
It's never getting over 162-167 on CLT, and all the fluids look good.
The INT's are steady at 128 and the BLM's are 132-134, which seems to be better with the new O2 than they were from the old O2 in there.
Once she's been running alittle bit and warmed up, she gets alittle stumble in her at idle. The fuel pressure isn't bouncing or dropping when that occurs, it's staying constant the whole time.
I still at this point can't drive her very far without her actting up. It's very odd what she is doing, i just haven't been able to pinpoint what it is yet which is frustrating. One of the things i have done was try the wiggle wires test and doesn't change anything. She starts great, just can't really drive her very far.

I did reset the ECM and still after she has relearned herself am having the issue. It's just plain weird and isn't making much sense.

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I have always set the fuel pressure to what the chip maker said it should be set at. Which with my current chip made for 60lb injectors it's set to 45 psi static "vac. line off ". adjusting the pressure with my Kirban fuel pressure regulator.I know i wouldn't use a stock bosch 233 fuel regulator with this combo.And i wouldn't use one with a TT chip made for 50lb injectors either,but thats just me and my simple thinking.

The coolant temp sensor sends a lot of information to the ecm so that it can make necessary adjustments for fuel and timing requirements that are needed.
With the vac line off, with the TT chip i have it would of been about 43psi that it would of called for.
With the vac line on it needed to read around 38psi, according to what is recommended for the baseline fuel pressures on these TR's.
Up until a few weeks ago, i hadn't had any issues with her. The mods have been on the car prior to me buying her back in Oct 2010, it was rebuilt back in 2010 and only had 100 miles on the rebuild when i bought her from the previous owner at the time. I was very careful with not running her too hard while finishing the break-in on the engine the next 500 or so miles from getting her. I had her transported on a transport truck from a town outside of austin down to where i am in El Paso, where she's called home since buying her and where i had broke her in.
I've put somewhere between 27k and 28k miles on her since owning her over the last 4 years, which is an average of around 6500 to 7000 miles a year on her. I guess i've been lucky she's been going that long or the person that did the work had to know what they were doing, with what had been done and that there was still some stock stuff on her.
There's 2 Coolant sensors near where you mentioned, one has a single green wire that plugs into it that is a round type connector which sits closer to the upper plenum and the other is closer to the Cam Sensor Cap wire harness more towards the front of the intake area. Which doesn't have only a single wire going to it.
You're talking about the one that has more than only a single green wire going to it correct, just making sure i'm not mis-understanding on which 1 you were refering to. I know the single wire one is suppose to be the one which is suppose to allow seeing what the coolant temp is via the Scanmaster or other datalogger device hooked into the ECM and also make the idiot light come on if the engine gets too hot, if i am recalling correctly.
I've been thinking it might of had to do with something messing with timing possibly, but something else could possibly be creating the problem. If i could monitor what the air / fuel ratio was doing, might of been alittle easier to troubleshoot her and resolve the issue faster. The one of many drawbacks of having limited monitoring abilities, makes trying to figure out what is wrong harder.

In some ways it seems weird that it might be a Coolant Temp Sensor issue, would think it would of thrown a code or possibly would be overheating if that were possibly malfunctioning. Not saying it isn't possible, but if the coolant temps are accurate on the scanmaster & the cooling fan is kicking on once it reaches 160 degrees seems like that might not necessarily be the issue.
The radiator is full with 50/50 prestone anti-freeze / coolant. No leaks or any fluids mixing together, no smoking out of the exhaust or anywhere else. No coolant or water going into the overflow bottle, so it can't be overheating. I know the water pump is working properly as fluid is being circulated through the whole cooling system.
No codes being thrown, but something is not actting right somewhere to be actting like she is. Not really sure what else to try at this point.
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Well after finally being able to get someone to look at the ol' girl on a lift last week, find out somehow the crank pulley isnt true anymore and it needs to be replaced. It hit the crank sensor and they had tried to straighten it but it's still not in spec. So am trying to find a crank pulley that has the mounting holes for the stock intercooler fan setup. Still trying to figure out how over time it even had become that way, so part of the mystery to why she was running a tad off finally was solved. The people that looked at her hasn't had luck finding a replacement with the fan mounting holes and thought i would see if maybe someone may of had a good one they pulled off their TR here they could part with. Thanks in advance for any leads and help with hopefully tracking one down.

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Sorry for such a gap of time on replying back, life been a tad rough but finally things turned around for me where i'll be able to have the ol' girl running again. Yeah thinking that is the case as the crank pulley itself appeared to be straight, of course it's probably the original solid balancer most likely since alot of stuff on her still mostly from when she rolled off assembly line in '87. I will around end of next month have bit of money ( my post 9/11 g i bill monthly housing allowance from starting back up in college 21st of this month will hit my bank account around then) to get her going again. Gonna be so nice getting her back on the road after all this time, guess it'll be summer cleaning etc instead of the typical spring cleaning these rare historic fun cars receive in this case. :D
I'll probably get a few other things tackled once she is at least running again.
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