ok so last night i goto start my car and it goes pretty much to 8000 or so rpm

i tried checking my tps and i got an ouch along with some pretty random numbers
i also disconnected it and it still started and went to 8k

i tryed searching and couldnt find anything

could a bad tps cause this?

 

what the hell are you trying to say?? i cant understand you

 

when i start my 87 rx7 n/a it immediately goes to 8000 rpm

i checked my tps and either dont get a reading at all or i get like a really high resistance reading not within spec

and i am asking if a bad tps could cause my car to goto 8000 rpm?

is that better?

 

your throttle body is stuck open, or a misadjusted throttle cable holding your plates open.

 

Definetly NOT a TPS problem. I'm with the guy above.

TPS should not give off random figures though, but even then a TPS cannot cause the rpms to go to eight grand...EVER.

Next time the engine is hot and idling under 800 rpm, ***** the GREEN/RED wire on the TPS connector (harness side of the connector, not the TPS pigtail side) and put your meter on the needle you pricked the green/red wire with. Should read approx one volt dc. If not turn the tps screw til it reads one volts. Done setting tps. Again, your problem is NOT a tps problem.

 

I say don't even mess with the TPS and leave it alone. Setting your TPS right now would be about as productive as changing your brake fluid or something, it has nothing to do with your problem.

A condition that severe will be easy to troubleshoot. A cable connects your gas pedal to the throttle body bolted to the intake, check to see if it is caught on anything. It should be quite obvious.

 

ok so heres what i got so far the top butterflys when i take the intake tube off are open but i assume they close once they close once they have vacuum to them


and i know its not my tps but i checked it got an ohm reading of 4.58k and it doesnt change once i open and close my throttle body

and i had someone step on the gas and it opens and closes fine

is there more than one cable that goes to the tb? ive been looking for pics but i cant find any

 

LOL!!! The butterflies do NOT close once they "get vacuum to them"...hahaha...Thats your problem man, it sounds like the throttle plates are seized. They need to be closed when the gas pedal is at rest. Try some WD40 to lubricate and clean them, then open/close them to confirm normal operation. You might have to replace the TB but they're cheap.

 

the top two butterflys that have the vacuum actuator and the vacuum line going to the actuator

 

ok i fixed it

sry for the way i worded some sentences i type it out and in my head it makes sense but on paper it doesnt

thanks

 

What did you do, exactly?

 

prolly unstuck the throttle plates ;P

poor s4 engine.. 7k redline :P

 

The double throttle system closes the outermost set of butterfly valves when vacuum is applied. While driving, opening the throttles drops vacuum, and a delay valve slowly opens the secondary throttles. Mazda did this to make the car easier to drive around town, and with a properly functioning system, it does.

Check out the FSM here:
http://www.rx7city.com/Manuals/88%20...ISSIONS_NA.pdf

Pages 59 & 60.

 

we all know that there is a delay in when the throttle plates open, but what this guy was saying was that one set of plates was all the way open even when the throttle cable was at rest. That is NOT how it should be. All three plates should be closed at full rest, and then they should open in stages when the cable is pulled (i.e. gas pedal pressed).

 

When the engine is off, even if the throttle cable is at rest, the outermost set of butterflies will be open, since they are only controlled by vacuum, not the cable. If there is no vacuum (I.E. engine not running or running at WOT) then they will be open.

 

I'd like to know what you did to fix it because I am having the same problem. I have an 88' n/a with some emissions removed by previous owner.


Mine started as a loping idle after I drove 1200 miles in a day and a half over the mountains. It would still run on the highway but fuel mileage dropped. On the way back 5 days later I stopped at a rest stop and when I started the car again the rpms climbed extremely high without touching the gas. I shut it off and checked the throttle and it wasn't stuck so I started it up again with the same result. I tried to drive it but it would cut out at 3000 rpm and I pulled off at a gas station. I messed with the throttle and tps to make sure nothing was stuck. After sitting there for about an hour I started it and it was back to the loping idle. I drove the 600 miles back home with no more high revving but just the loping idle. I let it sit for a few hours and tried to start it and it revved up super high again.

I checked the tps with a dvom and it was 1kohm at rest and as you moved the throttle it rose until at wot it went out of limit then showed over 4 kohms. Good according to specs except for the little blip of out of limit every time.

I took air intake off and butterflies are closed (except for outer upper ones as discussed above) They move fine with the linkage.

The last time I tried to start it it was smoking pretty bad and I really don't want to blow up the motor. Any help would be appreciated.

 

I'd PM the original Poster of this thread.and find out what he did to rectify the Problem
It Irks My Cookies to see Guys ask What the Heck to I DO?//..all Excited and Perplexed,wanting INFO,but when it comes to them "suddenly Getting an Epiphany" and Fixing thier Problem NOT posting the info To help Others who May want to Know..SHARING INFO is part of the Forum's Lifeblood..
Please man..post your solution so others can Learn.