Suspected Vacuum/Boost Leak
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Suspected Vacuum/Boost Leak
Hey all, just picked up my first rotary in a 1987 FC TII. When I bought it it was slightly leaking oil around the oil filter so I replaced the O-Rings and was good to go. I love the car, it’s so light and fun to drive, but when I start it up it does fluctuate in rpms up and down quickly at around 800 rpm before I start driving. At first when driving I noticed that my boost gauge wasn’t moving. At first I figured it was just a bad gauge but later I realized it would move, just very slightly (not even a few psi) when I absolutely floored it. Then I realized I wasn’t feeling or hearing the turbo whatsoever and the car sort of felt like it was lacking power. I suspect a vacuum leak somewhere in the intake system, since it’s not making boost I figure it’s somewhere before the turbo, causing no boost and that shaky initial idle. However there is an exhaust leak where the downpipe meets the cat so the car might be losing back pressure from there, causing the turbo to not spool, but I talked to a local TII owner more experienced and he said that if the leak was after the turbo it wouldn’t prevent it from spooling up. Planning on doing a compression test soon but I’m pretty sure the compression is fine. Anyone have any advice? Thanks.
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Forgot to mention that the weird idle usually goes away whenever the car is warmed up, so it’s probably just the engine warming itself up. It’ll go up and down then settle at 1000rpm after a few minutes, or I start driving while it’s doing it and by the next time I slow to a stop sign or red light it’s idling like normal.
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weird idle is the TPS, these cars are known for it. i would suggest checking the TPS seasonally (make a little tester that plugs into the diagnostic port), after about 3-4 seasons you can go longer.
the not having boost thing could be a ton of stuff, i would fix the exhaust leak first
the not having boost thing could be a ton of stuff, i would fix the exhaust leak first
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