Low/No Primary boost
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Low/No Primary boost
Hi all
80000km 2002 rx7 on stock twins
SBC Boost controller
PFC w/ commander
catback exhaust
Potential other mods, unknown. Car has come across from japan.
Symptoms:
2psi WOT in Neutral
Boost pattern 2-8-10
Not hearing any blowoff whistle that I used to hear in low revs.
I have checked:
No IC boost leaks
Cant find any other leaks.
Charge control Actuator pulled in when engine idling
Vacuum still present at charge control actuator after 5 mins of engine off
Same goes for pressure chamber, holds pressure well.
BOV and CRV both in good order. I do however note that when I revved the engine in neutral the ABV was pumping out heaps of boosted air. I imagine when there is load on the engine this is not the case.
Could it be something to do with my PFC or boost controller settings? I don't really understand the interaction between PFC boost settings and external boost controller settings. Which overrides which? Should PFC duty be at 100% (I read that somewhere).
I have a hand vacuum pump so am planning to test actuators in more detail tomorrow, but wondering if there is anything else I can be looking at.
Could the wastegate be stuck open?
The problem is not intermittent.
Any ideas or related information is appreciated. I've already spent countless hours looking through forums and found lots of relevant info but nothing that can rectify my situation.
80000km 2002 rx7 on stock twins
SBC Boost controller
PFC w/ commander
catback exhaust
Potential other mods, unknown. Car has come across from japan.
Symptoms:
2psi WOT in Neutral
Boost pattern 2-8-10
Not hearing any blowoff whistle that I used to hear in low revs.
I have checked:
No IC boost leaks
Cant find any other leaks.
Charge control Actuator pulled in when engine idling
Vacuum still present at charge control actuator after 5 mins of engine off
Same goes for pressure chamber, holds pressure well.
BOV and CRV both in good order. I do however note that when I revved the engine in neutral the ABV was pumping out heaps of boosted air. I imagine when there is load on the engine this is not the case.
Could it be something to do with my PFC or boost controller settings? I don't really understand the interaction between PFC boost settings and external boost controller settings. Which overrides which? Should PFC duty be at 100% (I read that somewhere).
I have a hand vacuum pump so am planning to test actuators in more detail tomorrow, but wondering if there is anything else I can be looking at.
Could the wastegate be stuck open?
The problem is not intermittent.
Any ideas or related information is appreciated. I've already spent countless hours looking through forums and found lots of relevant info but nothing that can rectify my situation.
#3
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Before this happened, I picked the car up from the mechanic, and was boosting then the boost (secondary) abruptly lost power. I found it later to be a hole in the IC pipe which has been repaired. I think it happened because my boost settings were too high, I was probably running more than 10 psi.
Since that repair I have been fine on the transition and secondary but low primary.
Yes I can confirm the primary turbo spins fine.
I started the car today and watched the turbo control actuator. Did not see any movement that the FSM says should happen, but the actuator works fine (tested it with pressure). Thinking this may just be a result of the external boost controlling devices?
Also tested the charge control actuator with a vacuum pump and found it needed 5 inHg to be fully pulled in. I believe it started pulling in around 2inHg which is consistent with the FSM.
Since that repair I have been fine on the transition and secondary but low primary.
Yes I can confirm the primary turbo spins fine.
I started the car today and watched the turbo control actuator. Did not see any movement that the FSM says should happen, but the actuator works fine (tested it with pressure). Thinking this may just be a result of the external boost controlling devices?
Also tested the charge control actuator with a vacuum pump and found it needed 5 inHg to be fully pulled in. I believe it started pulling in around 2inHg which is consistent with the FSM.
Last edited by 2-TIGHT; 03-13-23 at 04:36 AM.
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