My car is an 87 T11 and earlier today I stopped at the gas station, got back in to start her up after I finished pumping my gas, it started, but when I floored the gas it didn't do anything, the RPM's were just bouncing between 1300-1500 rpm. I'm not using TPS on my car or ACV, EGR, or BAC valves. I've done the TB mod, removed all emissions ****, and air pump and A/C. After I finally got the throttle to actually rev the engine up, I started driving and it kept wanting to buck like a damn bronco at the rodeo. At one time I pressed the gas and nothing was happening then it would finally catch and would go for a little bit and start bucking in the process. I got home hooked her up to my code checker and it was giving an o2 sensor code. Can that cause this or is it maybe the stock precat is clogged because it doesn't have the main cat anymore. Can someone please help?

 

Yup an O2 sensor can do funky things to the cars mine made me go into limp mode which is what yours was trying to do!
but yours seems to go into and out of limp mode! and well it advisable to get it replaced asap as limp mode ***** things up fast! i blew a fuse! cause of the block i drove in limp mode! i would have hated it if i was on the highway! Good luck

 

Thanks for the info, any suggestion on what kind of O2 sensor to go with?

 

UAP/NAPA sold me mine! i don't even remember what it was for i just debbited it! But it has been working real good all i know is i saved like 100$ from the factory one!

 

you can unplug the O2 and the car will still run fine... that code isn't your problem. check for huge vac leaks. check between the AFM and TB. and intercooler hoses if turbo.

that kinda sounds like the syptoms of a blown engine too...


and ah.... you kinda need a TPS....

 

Engine can't be blown just has little over 200 miles on it, I just rebuilt it. It ran fine without the TPS up until tonight when that happened. And I'm only running 2 vacuum lines, I checked those last night, and they're both fine. I don't think a vacuum leak would cause it to buck that badly, I'm talking like face in the windshield.

 

check the intercooler hoses and TID from turbo to AFM

 

just thinking check your MASS AIR METER? it could be malfunctioning! my car did nto buck that bad! like it did a bit but not that bad!

 

I checked the AFM the other day, with the FSM, and it tested good with an ohmeter.

 

Where's Kevin at, maybe he knows. YO KEVIN LANDERS. Where you at bitch?

 

You, uh, aren't using a TPS?
uh....
Hmm.

 

uhh... smackey, you cant just unplug an o2 sensor and have the car run fine!

 

sure you can. the O2 sensor is only used for light throttle driving, to maintain perfect 14.7 A/F ratios for best gas millaged and emmissions. the sensor is not used for idle or while mostly on the gas. without the sensor the car will just run a bit richer at light throttle. I ran mine for 2 weeks with it unpluged. only diff is the check engine light comes on. didn't even notice any diff in gass milage.

 

I'm sure there is a difference it just may not be as noticeable with a T2 like it is with a N/A. My 02 sensor was acktng weird ever since i put my RB header on. I replaced it cleared the code then would go for a drive. It worked for a while then the ck engine light would come on again. When it did it changes the cars throttle response, its not as snappy as b4 it also sounds like its missing at idle. But my problem was caused by oil leaking onto the 02 wire, got rubber tubing to cover the wire and ran the wire directly to the ECU and now its rock solid.

 

Ain't no such thing as a LIMP MODE on a 86-88, turbo or non-turbo.

 

Hailers: You sure about that? Try unplugging your AFM sometime and tell me what happens The TPS as well, for that matter - over 1/4 or so throttle the car will run like criz-ap.

That said, an O2 sensor will not cause that. Pulling codes on an S4 is like a rain dance, IMO - not worth much. I'd check for big vacuum leaks.

Brandon

 

I've checked, no vacuum leaks unless there's a crack in the TID. I bought a new O2 sensor really can't tell a difference yet but I haven't drove it yet. It hasn't done that thing it did at the gas station yet, but when the car is sitting and I floor it to rev it up it stutters then it revs up,but if I rev it slowly it's fine. Can this still be the secondary injectors not working or what? My friend's 87 T11 runs fine without the TPS so I don't think it's that, my car does the same thing with the TPS connected. And another thing, when I drive it after I've drove it for awhile and it gets warm it will cut out a little bit at cruise, like a light bucking. This was before I replaced the O2 sensor and like I said I haven't drove it yet so I don't know if it still does it.

 

HAILER'S IS MORE THAN SURE POSITIVE, that there is no limp dick mode in a 86-88 model RX-7.

 

so does anybody know the problem?

 

I know the problem.



The problem is...
























...that you're a bitch

There are a limited number of things that could cause the revving hesitation, etc. One of which that Ive thought more about is that vacuum hose that we've capped off on all our cars. Between the 2ndary oil injectors, which Im told is supposed to aid the atomization of fuel from the primary injectors. My car, George's car, and now your car, all have those little hesitation problems from time to time and I wonder if that isnt just a bit of the problem, especially since george's car ran fine before we perfoemed the TB mod/emissions removal/capoff. I have thought of reinstalling that line on my car to see if it helped, but alas, no time away from rebuilding/reinstalling engines.

You might also try running the AFM off your GTU for a while on this car...you already tried that, I know, but do a trial run for, say, a week and see if it drives any better now that you already fixed that major problem you did have.

Regardless, the problem is there, in front of you, under the hood. No one here, including me, can *tell* you what the problem is, they can only tell you their opinions and similar experiences, and in some cases, their plain old guesses. Like I said, this is one of those things that must be found by trial and elimination, swapping of parts, give it time, etc.

 

I would drive it but right now all the exhaust I have on it is that 3" downpipe...very very loud. I'm going tomorrow to the exhaust shop to see if they can rig up something for now. I'll try that, we'll see what happens.