I sprayed WD-40 and carb cleaner all around any hoses and intake gaskets, no idle changes occured. I did go through that list, the only thing that im skeptical about now is the MAF sensor, i may have bought a faulty one still.. could that be?
Weird idle issue, can anybody chime in?
- Thread starter modmonster2008
- Start date
No clue, probably the injectors that have been used since the car came out of production? Lol. Do injectors really cause those problems? As much as possible i hope the problem isnt the injectors, those would cost a good amount of money for replacements right?
modmonster2008;1724016 said:
Something you could do to see if it is the injectors causing the problem.. Unplug them to see if anything changes, one at a time of course. If the engine stumbles really badly you know it's not that one, then try another one. Rinse and repeat.
Is it normal to have replaced the coil pack already and my timing light still not able to pickup 3/6 of the coil signals? The left coil of each pack doesnt want to be read with my timing light, however, the right ones do. Removing injectors doesnt really seem to do anything.
EDIT: Injectors are within spec (has 3.7 ohms per injector), all were clicking using my stethoscope per TSRM instructions. The MAF has been replaced again and still runs rough, however idles better with my original maf sensor which throws a CEL and has a super rich fuel mixture out the exhaust.
Only things I can think of now, is either I have a faulty cold start injector circuit or switch, a faulty ISCV, or a bad TPS but the car does not throw any codes which really stumps me a lot!
EDIT: Injectors are within spec (has 3.7 ohms per injector), all were clicking using my stethoscope per TSRM instructions. The MAF has been replaced again and still runs rough, however idles better with my original maf sensor which throws a CEL and has a super rich fuel mixture out the exhaust.
Only things I can think of now, is either I have a faulty cold start injector circuit or switch, a faulty ISCV, or a bad TPS but the car does not throw any codes which really stumps me a lot!
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modmonster2008;1724210 said:
Well.. If you're not getting fire on the left side of the coils.. Have you checked all the wiring for the ignition circuit?
Yeah, all wiring is good no loose connections or anything, all ignition related stuff are within spec of the TSRM. What i don't get is, there are times when the idle is perfect, but i still don't get any reading from the left side of the coils, could it just be my timing light? Besides, if all three left coils are not getting anything, wouldnt it also run like crap? It runs great no rough acceleration, only on idle is when i notice the problem. I checked out yesterday I revved the engine, then upon deceleration i got a code 51 "No IDL signal, A/C, or TPS. So im going to check out the TPS maybe its the reason for the idle to be like that?
I am pretty sure if your running the engine in diagnostic mode and rev it you will get the code 51 because the tps is sensing the throttle not closed. As long as the code goes away when your throttle is closed (back at idle), thats normal. If someone else can confirm this?
There's a guy named Johnny Nguyen in Las Vegas. He shipped me some Nippon Denso 560cc injectors out of a Mistubishi EVO 8, low imp., top feed, plug 'n play if you have a Lexus MAF, and not guaranteed to fix your idle issues but I installed those puppies with my lexus MAF and man she idles purrrfectly everyday!
If the tps isn't calibrated correctly it could be causing your issues. Or if the tps isn't sending the right signal..
Correct me if I'm wrong on this.
Correct me if I'm wrong on this.
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I agree...and not sure if the car is barely running if the ecu would ever have the conditions to throw a CEL for it
Okay, so today i took her out for a long drive. After maybe about driving for about 30 minutes or so and i come to a parking lot or stop, the idle purrs perfect at around 700rpm. I don't know as to why its only acting up the first cold start, or after restarting the car after shutting it off. It's fine after a while, but at cold starts it wants to stall and does not even have the cold start idle at 1500rpm's and drop, its really confusing
That idle is weird.. and the symptoms are even more confusing.. as far as more help.. I've suggested everything I can think of as how to help. If I think of any more I'll be sure to post my suggestions.. but I'm at my wits end. Maybe one of the more experienced members could help.
Thanks for the help though, Id like to get as much help as i can get. So for further diagnosis, i have checked out the VSV for the fuel pressure regulator and the resistance fluctuates around 70-95 ohms depending on temperature and such (TSRM says b/t 38-44ohm) so im going to replace that and see what it does. I fiddled around with removing the vacuum hose from the FPR seems to have stabilized the idling a bit but then i got the rich fuel smell out the exhaust. So first I will get a working VSV off a junky supra and see what improvements occur. Btw is there any way to test out if the FPR is faulty or not?
Sounds wierd, like youve got bigger cams in. If the FPR was faulty maybe that would cause the surge. Not sure how you could test except get a gauge and plumb it in. My Aeromotive AFPR you can feel it regulating in the return line like a click.click.click fast and steady.
Now I'm no expert at electronics or anything related to any complex related stuff, but my dad and I used some TSRM wiring diagrams and connected the CPS to an oscilloscope there were two identical sine wave signals and one multiple frequency signal which I am going to assume is the output of the CPS. Based on my online research a "ring modulation" circuit consists of two identical input signals and one output signal that is nowhere near similar to the inputs. Now what I am curious about is when we checked out the output signal coming from the CPS there was a "magnetic effect" waveform as well as another wave overlapping it. Has anyone done these tests before, and/or know if there should be only one signal coming from one wire? Its making me lead to the conclusion that the CPS is the main reason of my erratic rough idle and whatnot, if anyone can let me know about that it would be greatly appreciated. Thanks!