Lean condition at certain mani. vac.
#1
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Lean condition at certain mani. vac.
88 TII Streetport w/ TID
For some reason, when I'm cruising at speed, when my vac guage reads between 2 and 12 inHg, the A/F guage goes all the way lean and the car hesitates and shutters a little. If it's as 12 inHg and I let off the gas just enough to get more vacuum, the A/F goes to 14.7. And when it's at 2 inHg and I hit the gas a little more, it goes to 14.7. Sometimes it does it and sometimes not. Is there a dead spot in my TPS or AFM? It did this before I installed the TID. Thanks.
For some reason, when I'm cruising at speed, when my vac guage reads between 2 and 12 inHg, the A/F guage goes all the way lean and the car hesitates and shutters a little. If it's as 12 inHg and I let off the gas just enough to get more vacuum, the A/F goes to 14.7. And when it's at 2 inHg and I hit the gas a little more, it goes to 14.7. Sometimes it does it and sometimes not. Is there a dead spot in my TPS or AFM? It did this before I installed the TID. Thanks.
#2
I'm a boost creep...
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That's the injectors shutting off when you close the throttle. All EFI cars do this. However if your TPS is out of adjustment the injectors will be shut off with the throttle still open a bit, causing the shudder you describe. You'll get the same thing when the injectors turn back on as the throttle opens.
You need to set your TPS.
You need to set your TPS.
#3
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i tried to set it and thougth i had it right, i guess i'll try again.
i set it by using an volt meter. adjusted it screw until i had 12 volts on one and none on the other (on the TPS check connector). give or take a few tenths of a volt. is that correct or did i do it wrong? thanks
i set it by using an volt meter. adjusted it screw until i had 12 volts on one and none on the other (on the TPS check connector). give or take a few tenths of a volt. is that correct or did i do it wrong? thanks
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Originally posted by fstrnyou
i...adjusted it screw until i had 12 volts on one and none on the other...
i...adjusted it screw until i had 12 volts on one and none on the other...
#6
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The output on the green/red connector is the one that should show one volt when the tps is set right. With the stipulation that the engine is fully HOT when you do the setting. All plugs should be connected up when you do that. Put your meters lead in the back of the green/red wires socket in the plug.
And for what it is woth.....if one has a wideband and you are at a steady speed and then you just barely let off the throttle and I mean barely, just a hair......the afr will go rich about a full point,. As in the reading was 14.6 and you let off a hair, the reading will go to approx 13.6. That is normal. All RX7 do that. It's a trait.
I'm not talking about letting off enough where the fuel is cut.....as in deceleration. Acually this can be seen on a regular 02 sensor using a voltmeter.
And for what it is woth.....if one has a wideband and you are at a steady speed and then you just barely let off the throttle and I mean barely, just a hair......the afr will go rich about a full point,. As in the reading was 14.6 and you let off a hair, the reading will go to approx 13.6. That is normal. All RX7 do that. It's a trait.
I'm not talking about letting off enough where the fuel is cut.....as in deceleration. Acually this can be seen on a regular 02 sensor using a voltmeter.
#7
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I've read a lot of posts where you say adjust TPS till voltmeter reads 1 volt. But that's been for the S4 cars. What do you adjust to on a S5? I've done the light thing, but I wonder if there is an actual voltage I could adjust to and what connectors to test for that voltage on.
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#8
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oh, why does the motor have to be hot. as long as the throttle is closed it shouldn't matter. if you say this because of the thermowax thing, i have mine disabled.
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*******oh, why does the motor have to be hot. as long as the throttle is closed it shouldn't matter. if you say this because of the thermowax thing, i have mine disabled.****
Because of *the thermowax thing* and the fast idle cam. If you don't have one...then it shouldn't matter if the car is hot or not.
Because of *the thermowax thing* and the fast idle cam. If you don't have one...then it shouldn't matter if the car is hot or not.
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also, new discovery, when i altered the signal coming from the boost sensor, my car goes lean at a different spot. does this mean that when my ECU reads a certain voltage that it goes lean. I used a resistor to lower the voltage going to the ECU and now it goes lean from about 10inhg all the way to like 5 psi. so whatever voltage my ecu is getting, it goes lean in that certain range. Is my ecu bad or something?
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