Hi, i just bought a 88 Rx-7 convertable (non turbo, 5 speed manual), its my first rx7 (i got it for $800, the guy i got it from thought the tranny was shot because it has such a sloppy shifter it has 130k on it, and is completly stock), any ways when i nail the gas pedal hard,(from a complets stop)it kind of sputters, then the rpm goes up fine, the other thing it does is runs kind of rough at 3k if its stopped and im revving it and stop there, no problems driving it at 3k.

Any help would be appreciated

Tom H.

 

I tracked the problem down to a vacuum leak, and raised my idle up to 1k, that seems to take care of the problem, but the car does run horribly in the cold for about the first 5 minutes

 

What do you mean 'in the cold'? Cold air temperatures or the coolant temp regardless of the weather? Also, in case you've been doing this, you should not be pushing the car hard until the motor has warmed up.

 

Yeah, in cold weather, the car is going to idle higher than normal for the first 5-10 minutes, I have a '90 N/A and I let it just warm up for about 15 minutes before I do any driving. Also I could be wrong on this, but I have a buddy that has an '88 N/A and he had a sputtering and 3k brickwall problem (like wont rev any higher than 3k) , I troubleshot that at a compnent level, and it turned out to be a bad ground to the ECU. Might wanna check there too. Just a suggestion though.

 

Search for the grounding faq

 

i meant in the cold air temperature, it idles really rough until it warms up, most of the time it will kill (when doing the sputtering thing) unless i keep it above 1000rpm,some times the rpm fluctuates rapidly from 800-2000rpm (without me touching gas peddle), but i found another bad vacuum line (just got to find where it goes), my tps is out of whack, and my smog pump is not working right, so i have to check out those things (and remove the smog pump), and also should the exhaust be "glowing" red (right before the first cat) after you are done driving it hard?

get this, i got two sets of rims/tires with the car, and i sold the ugly "ghettoish" rims for 650 to some moron, offsetting the price of the car to 150, the rims i sold looked horrible on the car, and they rubbed pretty bad

 

Your TPS is probably bad. I had a similar rough idle during warm up that was fixed by replacing it. It would bounce until the idle got down to ~900 RPM, and had a rough spot from 1k to 1.3k. Now it idles smooth at any RPM.

The problem you mentioned with a studder right off the line is similar to another I fixed awhile back. Turns out my fuel filter (which wasn't all that old) was partially plugged up, and it would cause the car to bog down for a second once the clutch was let out all the way. Other things to check are the hard fuel lines (to make sure a previous owner didn't smash or damage them), and the voltage at the fuel pump.