All those nagging problems finally fixed... (long)
10-19-01, 12:48 PM
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All those nagging problems finally fixed... (long)
After thousands of dollars, I've finally reached the next level of RX-7 goodness. I've had my 3rd gen for about a year and a half. I got it with 37k miles and now it has just 40k miles. Everyone who looked at it orginally said it was in "pristine" condition. Well, let me say, there is pristine and then there is pristine. It was bone stock and had quite a few very subtle problems, that I think a lot of people have and aren't sure if that's just an RX-7 quirk or a real problem. Here's what I've recently attacked:
1. Idle would sometimes dip down and want to die after heak soak or when idling too long. Or idle would fluctuate up and down when idling too long.
2. Car ran too hot. This means the temp gauge would threaten to go above the "middle zone". Also, sometimes fans would stay on after turning the car off. Yes this is normal, but should only happen under extreme conditions. Driving around the city, no matter how hot, it not extreme.
3. Boost pattern seemed inconsistant, and was not linear with the throttle. This means, I would have to really jam the gas, and then suddenly boom, boost. Boost would not come on under light throttle, even under heavy load (ie lugging 5th gear on the Fwy).
4. Very small oil leak. Undertray always seemed "wet", and once in awhile a drop would end up on the driveway or garage floor. RX-7s are not supposed to leak!!!
5. Oil pressure gauge was not consistant. Sometimes I'd see 0psi at idle (gee who hasn't had this happen?).
6. Gas mileage seemed a little low for a stock car, also, car smelled like gas at idle, seemed too rich. (Remember car was bone stock w/regards to this stuff).
Now all these problems are fixed. THANK YOU MAZDATRIX!!! Some were a combination of several things so I won't try to isolate the fixes. Now:
1. Idle smooth and consistant. Never fluctuates, air on, hot day, cold day, fans on, air off, fans off, whatever. The proper behavior is for the idle to hold a little over 1000 for a few seconds upon coming to a stop, then to drop to around 850 or so (this can be adjusted). The main point is the idle shouldn't waver around. Electrical load raises it slightly, but it should never hunt. Also, car pulls 19-20inHg at idle. (Not sure what it was before because I didn't have a boost gauge).
2. Car runs cool now. 180F degrees on the Fwy, can get up to 200F if I idle long enough, then fans come on and it goes back down until fans shutoff again. With A/C on, 180 all the time even in rush hour. The fans used to be overworked, no anymore.
3. Boost pattern perfect. 11psi (gauge is probably 1psi off) with barely perceptable dip and then 11psi. Must do more testing to fully verify boost pattern, but "feel" is excellent. That is, boost is always nearly instantaneous, it never feels like it needs to "kick" in. Also, now under heavy load, very little throttle is needed to produce boost.
4. Undertray is bone dry. No leaks. Nothing. No smoke, of any kind, from anywhere. Nothing.
5. Oil gauge fixed. Yes I did it the expensive way
6. 19mpg MIXED hwy/city
What was done:
Rebuilt turbos. All gaskets around turbos replaced, as well as LIM gasket. Entire vacuum system diagnosed, replace one check valve, one solenoid, many hoses replaced w/silicone. Y-pipe coupler replaced with silicone. Fluidyne radiator. New themostat. Air bypass control valve cleaned. New plugs. New oil temp sender.
Thanks a bunch to John at Mazdatrix, John knows the 3rd gen vacuum system like the back of his hand, and he only fixed what needed to be fixed. AH ITS DONE I'M SO HAPPY!
1. Idle would sometimes dip down and want to die after heak soak or when idling too long. Or idle would fluctuate up and down when idling too long.
2. Car ran too hot. This means the temp gauge would threaten to go above the "middle zone". Also, sometimes fans would stay on after turning the car off. Yes this is normal, but should only happen under extreme conditions. Driving around the city, no matter how hot, it not extreme.
3. Boost pattern seemed inconsistant, and was not linear with the throttle. This means, I would have to really jam the gas, and then suddenly boom, boost. Boost would not come on under light throttle, even under heavy load (ie lugging 5th gear on the Fwy).
4. Very small oil leak. Undertray always seemed "wet", and once in awhile a drop would end up on the driveway or garage floor. RX-7s are not supposed to leak!!!
5. Oil pressure gauge was not consistant. Sometimes I'd see 0psi at idle (gee who hasn't had this happen?).
6. Gas mileage seemed a little low for a stock car, also, car smelled like gas at idle, seemed too rich. (Remember car was bone stock w/regards to this stuff).
Now all these problems are fixed. THANK YOU MAZDATRIX!!! Some were a combination of several things so I won't try to isolate the fixes. Now:
1. Idle smooth and consistant. Never fluctuates, air on, hot day, cold day, fans on, air off, fans off, whatever. The proper behavior is for the idle to hold a little over 1000 for a few seconds upon coming to a stop, then to drop to around 850 or so (this can be adjusted). The main point is the idle shouldn't waver around. Electrical load raises it slightly, but it should never hunt. Also, car pulls 19-20inHg at idle. (Not sure what it was before because I didn't have a boost gauge).
2. Car runs cool now. 180F degrees on the Fwy, can get up to 200F if I idle long enough, then fans come on and it goes back down until fans shutoff again. With A/C on, 180 all the time even in rush hour. The fans used to be overworked, no anymore.
3. Boost pattern perfect. 11psi (gauge is probably 1psi off) with barely perceptable dip and then 11psi. Must do more testing to fully verify boost pattern, but "feel" is excellent. That is, boost is always nearly instantaneous, it never feels like it needs to "kick" in. Also, now under heavy load, very little throttle is needed to produce boost.
4. Undertray is bone dry. No leaks. Nothing. No smoke, of any kind, from anywhere. Nothing.
5. Oil gauge fixed. Yes I did it the expensive way
6. 19mpg MIXED hwy/city
What was done:
Rebuilt turbos. All gaskets around turbos replaced, as well as LIM gasket. Entire vacuum system diagnosed, replace one check valve, one solenoid, many hoses replaced w/silicone. Y-pipe coupler replaced with silicone. Fluidyne radiator. New themostat. Air bypass control valve cleaned. New plugs. New oil temp sender.
Thanks a bunch to John at Mazdatrix, John knows the 3rd gen vacuum system like the back of his hand, and he only fixed what needed to be fixed. AH ITS DONE I'M SO HAPPY!
10-19-01, 01:11 PM
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Sounds like you are ready to have fun Nathan!! I have Pettit's basic HP upgrade installed( Catback,power pulleys, and intake). Also have a downpipe. My boost guage shows a bit of creeping so i ordered an unlimited ecu and boost controller for my next mods. While I'm at it i am going to do the midpipe and smog elimination kit. Also upgrade to a race radiator! Have fun with your car!!! G....
93 base.Montego blue BPU+
92 lumina(daily ragger)
93 base.Montego blue BPU+
92 lumina(daily ragger)
10-19-01, 02:30 PM
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Re: All those nagging problems finally fixed... (long)
Originally posted by Nathan Kwok
6. Gas mileage seemed a little low for a stock car, also, car smelled like gas at idle, seemed too rich. (Remember car was bone stock w/regards to this stuff).
6. Gas mileage seemed a little low for a stock car, also, car smelled like gas at idle, seemed too rich. (Remember car was bone stock w/regards to this stuff).
My car also seems to be running to rich, especially at start up... Did you ever figure out exactly what was causing the car to run too rich? My exhaust has a very strong fuel smell and I haven't been able to figure it out. Maybe I should take my car to Mazdatrix...
10-19-01, 04:23 PM
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Originally posted by twinturboteddy
i'll ask the evil question.
How much?
i'll ask the evil question.
How much?
how much did u spend?
maybe i need to take my car to John at mazdatrix... (boost, vaccume problem)
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