Having boost issues with my 1JZ SC300.
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Having boost issues with my 1JZ SC300.
Well we finished the swap, after some transmission linkage problems the motor fired on the first try, idled decent, sounded great. No abnormal smoke, no odd noises. Since the first drive we haven't been able to build any boost......... at first I thought it may have been because my friend "vented" the factory blow off valve, but we put it back to stock. We thought it could be the intercooler, but it was pressure tested up to 30lbs and it's SEALED. While the intercooler was off we checked for air being forced on the hot side piping, and there is forced air from the turbos. I'm 100% positive it's not the turbos..... they sound healthy, no death wine, no smoke - and they are obviously spinning air. Our boost reading is coming from a port on the intake manifold. Is there anyone who has any idea on this? I need some help troubleshooting here. Could this be a sensor? Possibly the turbo pressure sensor that's present on the intake side? We haven't yet checked each individual pipe/section of the intercooler route, but even if there was a small leak I'd think there would be some boost being built.
#4
bad boost gauge? or did you pinch shut the line when you put in on the back of the gauge? If you feel boost through the pipes there is boost... Check for any and all leaks at all the connections..Also check and see if the BOV is bleeding... I have had many a nissans do this
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Originally Posted by Tommyd1919
bad boost gauge? or did you pinch shut the line when you put in on the back of the gauge? If you feel boost through the pipes there is boost... Check for any and all leaks at all the connections..Also check and see if the BOV is bleeding... I have had many a nissans do this
#6
So if turbos are good as you claim, and there are no leaks from the turbo outlet all the way into the intake manifold. Then the only thing that would prevent the system from building boost is the wastegate(s) being stuck open or the the wastegate swing valves being loose from the acuator rod.
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Originally Posted by nasc300
So if turbos are good as you claim, and there are no leaks from the turbo outlet all the way into the intake manifold. Then the only thing that would prevent the system from building boost is the wastegate(s) being stuck open or the the wastegate swing valves being loose from the acuator rod.
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#8
if the bov is recirculated like stock then it shouldnt matter, it would just build less boost and be jerky. if it is not recirculated even with a leak it would still make boost it just would be inconsistant boost figures.
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Thanks for the reply. We are going to pressure test the entire system tonight looking for leaks.... the intercooler piping has to be the problem. I can't think of anything else that would cause this massive of a leak. The turbos sound very healthy, no smoke, and they sound very good.
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Originally Posted by Idrewfelix
Check the vacume lines; wastegate not holding boost, or turbos are seized
And they say the 1jz swap is more realiable
And they say the 1jz swap is more realiable
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If your BOV is leaking or not holding the engine wouldn't run as well as you're saying it is. An air leak is very evident and you should know right away something is wrong. So your car isnt exactly "Running great" when you just said its slower then a stock 2j.
If your turbos are spooling and pressure is being delivered, then there is nothing wrong with the wastegate. There is either an air leak or something is wrong with your motor (compression test).
If your turbos are spooling and pressure is being delivered, then there is nothing wrong with the wastegate. There is either an air leak or something is wrong with your motor (compression test).
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Originally Posted by Idrewfelix
If your BOV is leaking or not holding the engine wouldn't run as well as you're saying it is. An air leak is very evident and you should know right away something is wrong. So your car isnt exactly "Running great" when you just said its slower then a stock 2j.
If your turbos are spooling and pressure is being delivered, then there is nothing wrong with the wastegate. There is either an air leak or something is wrong with your motor (compression test).
If your turbos are spooling and pressure is being delivered, then there is nothing wrong with the wastegate. There is either an air leak or something is wrong with your motor (compression test).
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just double check all the charge piping vaccuum lines are a must to check also could be a boost leak at the injectors one of the most commonly missed problems with a car not making boost