So I last year I had this problem of breaking up around 3000 to 3500 rpms in 1st. Now while just idling, it doesn't want to go past 3000 rpms. What could be the problem?
1jz break up around 3000 rpms, wtf?
- Thread starter wornoutsupra
- Start date
I assume by idling you mean sitting still.
What's causing the cut out at 3K? It has to be either a spark, fuel, or compression problem.... so start eliminating what it's not if you don't know what it IS.
Check compression, low compression could indicate a slipped timing belt. Fuel pressure ok? Injectors still firing? (check with a mechanics stethoscope or a screwdriver) Spark ok? (good plugs, coils not cracked) System voltage good? (battery above 12V key off, 13.5v running?). Pull out a DVOM and test the major sensors, TPS, MAP, O2.
Anything happen recently that might have damaged something to cause this, any other known problems?
I'm drunk, so bear with me here.
What's causing the cut out at 3K? It has to be either a spark, fuel, or compression problem.... so start eliminating what it's not if you don't know what it IS.
Check compression, low compression could indicate a slipped timing belt. Fuel pressure ok? Injectors still firing? (check with a mechanics stethoscope or a screwdriver) Spark ok? (good plugs, coils not cracked) System voltage good? (battery above 12V key off, 13.5v running?). Pull out a DVOM and test the major sensors, TPS, MAP, O2.
Anything happen recently that might have damaged something to cause this, any other known problems?
I'm drunk, so bear with me here.
Ha well it has plenty of fuel, I am going to check spark today, to make sure the coil packs are not cracked. What about the crank angle sensor, is that possible?
http://www.supramania.com/forums/showthread.php?127857-Unique-1jz-3k-rpm-breakup
Doesnt sound like your having the same issue, sounds more like youre in limp mode. But its a good read.
Doesnt sound like your having the same issue, sounds more like youre in limp mode. But its a good read.
Nice thanks for the reading man, Idont have the time right now to read it though. Did you ever figure out your problem? So far i have read cam angle sensor and or cracked coil packs.
I had a similar problem, turned out to be a kinked fuel line between the filter and the tank. If you removed the tank it could've done the same thing too if you didn't disconnect it before lowering it.
Is it breaking up in the other gears, or no?
Fuel restriction isn't out of the question, but if you have proper fuel pressure while the problem is happening then that rules out a restriction. I'm not sure if you checked the pressure, or if you have a gauge to do that, but a quick and cheap way to check for a restricted fuel line is to remove the fuel return hose back at the tank and put a long piece of hose run into a gas can. Then see if a steady stream of fuel comes out of that hose all the time, even while revving the car. It should. The fuel pump is always pumping an excess of fuel to the rail, and so the extra fuel should always be returning to the tank.
Be careful whenever working with fuel btw... I had a car catch fire doing this once because I disconnected the underhood return hose to do this and the hose I used had a hole in it and dripped on the distributor.
Breakups like this are really a bitch to diagnose though.. systematically checking everything till you find the problem is the best way. Don't take anything for granted (that there's enough fuel just because the exhaust smells rich for example).
Fuel restriction isn't out of the question, but if you have proper fuel pressure while the problem is happening then that rules out a restriction. I'm not sure if you checked the pressure, or if you have a gauge to do that, but a quick and cheap way to check for a restricted fuel line is to remove the fuel return hose back at the tank and put a long piece of hose run into a gas can. Then see if a steady stream of fuel comes out of that hose all the time, even while revving the car. It should. The fuel pump is always pumping an excess of fuel to the rail, and so the extra fuel should always be returning to the tank.
Be careful whenever working with fuel btw... I had a car catch fire doing this once because I disconnected the underhood return hose to do this and the hose I used had a hole in it and dripped on the distributor.
Breakups like this are really a bitch to diagnose though.. systematically checking everything till you find the problem is the best way. Don't take anything for granted (that there's enough fuel just because the exhaust smells rich for example).
yeah well I got it to go past 3000 rpms, and its a stupid reason I never noticed the coil over cylinder 1 was unhooked. Now it doesnt want to break up around 4k but I think I still have to tune my safc a little. Also I checked all the fuel lines and they are good to go, no kinks or anything bad, and checked the coil packs and they look decent, no cracks that I could see atleast. The plugs seemed fine also, but I did forget to check the gap. Does anyone know what the ture gap on the plugs is suppose to be.