What is limp mode like? I have a code 52 and sometimes when idling it'll rev from 1000-1500 up and down by itself. Other times it bogs down to below 500 after letting off the throttle and will come back to regular idle in 2 seconds
What is limp mode like?
- Thread starter reincaster
- Start date
reincaster;1516209 said:
Code 52 does cause the ECU to go into a fail safe mode, but that wouldn't explain your problem; the car would still run "decent" (less power and worse gas mileage is all you would notice). You do need to fix your knock sensor issue (probably just the wiring) but this is something else...you're sure 52 is the only code you have?
Ok maybe not 100%, but I could feel a HUGE difference, once I fixed my code 52. She runs so much smoother with 52 a thing of the past.
I really, really wish the term "Limp Mode" would go the way of the dinosaur. The correct term is Fail-safe mode (as Ben said) and it can occur as a result of 11 different sensor malfunctions - each with a different TCCS response to the problem that generally involves setting a fixed value for the sensor input with the problem. Two of them (code 14 and 34) will simply stop the engine by terminating fuel injection. Code 52 will set timing retard angle value at it's max...that is why the car runs like crap (sluggish, no power). The whole purpose of Fail-safe is to get the car to where it can be fixed - I suggest that happen ASAP.
Ben is also correct that a code 52 will not cause the idle problem you described. It sounds more like a code 51 - the ECU is not getting the IDL signal that tells it to go into idle mode. It's also possible you have a vac leak somewhere.
Ben is also correct that a code 52 will not cause the idle problem you described. It sounds more like a code 51 - the ECU is not getting the IDL signal that tells it to go into idle mode. It's also possible you have a vac leak somewhere.
Battery light came on, and I went to the local NAPA and had it checked, turns out the battery is old and deteriorated, and the alternator is charging weakly. They have the alternator in stock, but at another branch, so I'll be getting one tomorrow, along with a new battery. My theory is a bit far fetched, but here goes: battery is weak to the point that starting it drains the battery fairly well, causing the car to idle low and rough right after start for 10-15 seconds. Alternator only charges to 12.5 v, and taakes longer to charge battery causing the idle to stay low until it charges enough. giving it gas draws more current that the damaged alternator can recharge, causing it to idle low after releasing throttle. (you can smell some gas as well).
As for vac hoses, I'm still searching my local parts stores for 3.2-3.5mm ID hose. Is there a way to pinpoint the leak, if there is one? cygnus states that an intake leak causes the vacuum to stay at a steady 5-6 inHg. On my bike I sprayed water on the intake boxes and waited for a change in idle to find the leak, however, with the extra electronics on the supra, I don't think spraying water or starter fluid is a good idea.
No code 51, but checking the tps couldn't hurt, and i'll try cleaning the iscv, even though I hear clicks after I shut off the car.
As for vac hoses, I'm still searching my local parts stores for 3.2-3.5mm ID hose. Is there a way to pinpoint the leak, if there is one? cygnus states that an intake leak causes the vacuum to stay at a steady 5-6 inHg. On my bike I sprayed water on the intake boxes and waited for a change in idle to find the leak, however, with the extra electronics on the supra, I don't think spraying water or starter fluid is a good idea.
No code 51, but checking the tps couldn't hurt, and i'll try cleaning the iscv, even though I hear clicks after I shut off the car.
The best way to check for a vacuum leak is to narrow it down by listening, then very carefully spray carb cleaner/brake cleaner/starting fluid in the area that you suspect the leak.
Do it when the engine is cold so there are no hot parts for the flammable fluid to combust on.
Do it when the engine is cold so there are no hot parts for the flammable fluid to combust on.
new and properly adjusted tps does nothing, unfortunately. Attacking the ISCV valve in the morning, and sourced the appropriate size vacuum hoses locally, gonna pick them up tomorrow as well