Weirdness and Questions, Newbie Celica owner / Newbie Mechanic Options

[94yotaGT]

Hello fellow Celica owners!

The name is Chris and its nice to meet all of you!

Ok so first I guess the backstory:

My brother bought this Celica from a buy-here lot in Kentucky and used it as a drive car for work, I assume it was in limp mode from the point of purchase. From that point he put maybe 5k miles on it, slapped a guardrail AND put it under the trailer of Semi. I got the car for driving him back and forth to his worksite while he was unable to do so legally.

So now onto the Weirdness and Questions:

When I got the Celica it had CEL/MIL with code 12 (RPM Sensor), I changed out the Dizzy and the CEL was gone, not much else seemed to change. Still misfiring slightly at low rpm and idle (1.2k and under) [sometimes after a long long drive, say 400ish miles, the car will idle down so far it has died 1 time, no spitting or sputtering, just low idle w/ misfire and then die]

It is leaking oil from the valve-cover gasket (already got a new one just waiting for good weather to put it on) but (forgive the noob question) would that also cause there to be some oil in the area under the rubber boot shield (sorry don't know the proper name for the square impression the valve cover that the square rubber boot lid sits just in)

[Picture of oil in boot impression and on line above the oil fill cap]


[Picture all four cylinders boot impression]


[Picture of third plug bore] (all bores look just like this one give or take]



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I read in a few Celica threads that the engine being out of time can cause oil in the plug bores and can cause the spark plugs to foul out quickly, I also know from common knowledge that an engine being out of time can also cause hard-start and misfiring. (Which I have a sinister feeling my car is in LIMP and Misfiring because it is out of time. The car at this moment has 257k on it and the last marked Timing Belt service was 101k in '06)

So I guess I would just like some thoughts on what I have said above, maybe I have missed something or am not thinking about something simple, but now for part 2!

Firstly let me say, my clutch engages very nice. I don't feel any slipping on take-off or on decel. But say for instance I'm moving down a city street at 30, well you would only keep light throttle to cruise at 30. If I keep light throttle the car I don't wanna say 'JERK' maybe lunges back and forth. BUT ONLY when putting on light throttle or letting off light throttle. For instance; if you gun it as the clutch engages you won't feel it, even if you just begin accelerating normally as the clutch engages you won't feel it. But let off the throttle after very short acceleration after the clutch engages and the car will exhibit the lunge. Also if you are going say 30 and just let off the gas and then get back on it you will feel it lunge.

However during these 'lunges' the rpm/sound/feel of the motor never changes, which leads me to think it is drive-train related, but I could use some advice and good places to start in relation to this!

So...in short, hope I have been concise. Nice to be a yota owner and I hope for some solid discussion and suggestions!

Chris