SkyWalker

ok, my car will run smooth 4 a bit until it warms up. But in 1st and 2nd gear every slight touch on the gas will make the car jerk or hesitate violently, especially around 3k. If I barely touch the gas she'll spudder down, but if I feed it more RPMs she fine? could the problem be vacuum leaks or in the throttle body or what?

RRTEC

iTrader: (13)

I bet that your fuel filter (intank and inline) are clogged, thus probably clogging your injector screens... My 88 Vert did the same thing, i ended up having to clean the screens on the injectors and drain the fuel tank to remove all the debris.

Tiers

also check tps, check for loose cracked vacuum lines...filter possible but ...

phoenix7

make sure your TPS is within specs.

lax-rotor

iTrader: (1)

I had a similiar problem crop up and went through this. The band-aid only lasted for two days or so, but it was enough to get me here and net me 22.77 MPG on the Highway, which is alot higher than what I was normally getting. This will only work if it IS the TPS.

platinumyama32

how does it run in the driveway in neutral? free-revving

just out of curiosity..

SkyWalker

fine. . .except between 1500 and 2000 RPM, if I hold it steady she'll drop then rise back, drop and rise and so on. .

turboIIrotary

iTrader: (9)

its your tps get a new one your ride will be much smoother

SkyWalker

whats the best way to test it?

phoenix7

pull out the FSM, get your trusty volt meter, follow instructions. Pretty simple. I am not hardcore enough to remember it off the top of my head though. The search feature might help you.

number one rule: car has to be warmed up to operating temperature. The problem I ran across was that I was slow. The car cooled down while I was testing mine so it wouldn't be within specs when I was finished. A friend might be helpful too.

lax-rotor

iTrader: (1)

Depending on how fubared the TPS is, you don't even have to test it while it's on the car. Just measure resistence while it's off. You can find the dead spots on it that way.

phoenix7

ok, good to know. I guess you can do the full sweep with it in your hand as opposed to having a friend do it with it attached.

lax-rotor

iTrader: (1)

Haha, yeah. Also I recommend an analog Multimeter. It provides finding the dead spots that much easier (for some reason all the digitals I used went nuts when I slowly moved it through the range).

phoenix7

voltmeter > LED method?

Vmeter worked fine for me so there was no need for the LEDs but it seems like the vmeter would be more accurate, no?

lax-rotor

iTrader: (1)

Yes. at least if you're trying to band-aid it like I was. With me I was trying to locate the dead spot. I found it and was able to fix it up with out much trouble. I imagine the LED method wouldn't allow you to see how much the dead is affecting the sweep. etc.

I'm curious though... why isn't there more aftermarket TPS products? I'm surprised that no one is producing them since a brand new one cost $200, where I'm sure you could just pick up a spring, a variable resistor and put it together for under $25. Sell 'em for $50 and you make 100% profit and you under cut the OEM by 1/4.

SkyWalker

That's what I'm trying to avoid, buying a $200 dollar replacement, by seeing if this one's within specs. . .which I'm getting ready to test now, but I'm not to sure on how to adjust it. . .that's my problem.

phoenix7

why not? You should have found plenty of info on how to adjust it. It's also in the FSM.

krad1975

I have some questions about my 1991 RX7 that I just purchased and I can't figure out how to post questions on this site! Can you help me with this? Thanks, Krad

phoenix7

https://www.rx7club.com/search.php