HELP: Hesitation above 3k RPM
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HELP: Hesitation above 3k RPM
Hello, I recently picked up an 84 rx7 with a fuel injected 13b and I am new to the rx7 world. When I got the car, it had sat for a year and was not running because the fuel pump was not comming on. Anyways, I got that problem solved and the car runs. I can rev the engine in neutral and it will rev out all the way, but when I am driving, the car wil get a little over 3000 RPM and then stop accelerating and begin to buck and studder. Any ideas on what is going on? Thanks, Ryan
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OK... thats what I was thinking. I need to drain the tank and replace the fuel filter for sure, god only knows what got built up in there when it sat for a year. Any other suggestions that might help? Thanks!
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If you're having still having trouble after changing the fuel filter, I would suspect the converters. They also can cause the symptom that you described. When they start to clog up, (if they're original than that's entirely possible), they'll let the engine freely rev all the way under no load. But when the car's in gear they'll choke off the engine as back pressure rises at 3k rpm and higher.
Let us know how you make out with the filter.
Let us know how you make out with the filter.
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ok... so I replaced the fuel filter and it still runs terrible.... each time I drive it, it seems to get worse and worse..... while driving it now I can get it to go above 2000 rpm. looks like ill be pulling the cats tomorrow
and just revving it in neutral it wont go above 5k....
and just revving it in neutral it wont go above 5k....
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If you're having still having trouble after changing the fuel filter, I would suspect the converters. They also can cause the symptom that you described. When they start to clog up, (if they're original than that's entirely possible), they'll let the engine freely rev all the way under no load. But when the car's in gear they'll choke off the engine as back pressure rises at 3k rpm and higher.
Let us know how you make out with the filter.
Let us know how you make out with the filter.
i have a rb exhaust system and it seems like its doing that and i have no cats.
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Its weird because I first got it running for the first time in a year and I let it idle for like 15 min and at first it ran great, I had it revving out to 6k and then after driving it for a little while it had gotten progressively worse
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I may be mistaken, but I don't think that the intake manifold for FI has a shutter valve. (I'll check my manual at the office). The shutter valve was made to shut of the fuel mixture from the carb to the rear rotor during deceleration (sp?) for emissions purposes. I would think that the microprocessor for the injection system would do this via the injector. Hopefully someone more familiar with FI pipes in here. I'm an old school carb guy.
Check for spark and let us know.
Check for spark and let us know.
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I think it could be a number of things including bad fuel pump/ lines could be gummed up/ bad injector /etc. I would check fuel pressure, I would also check the timeing just incase. Did you do a compression test on the car when you bought it?
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alright thanks, Ill have to check the fuel pressure for sure because Im thinkin the pump might be going out, or any of the other things said make sense too. Is there a fuelpressure check valve anywhere on the fuel line/rail? or do you have to install a gauge in-line? Ill get to that this weekend and let you know how it goes. Thanks, Ryan
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