ok so im tracking down these gremlins. i have a code for iat, vss, and tps. my car has a very high idle. also wont rev past 5k most of the time. no fast idle control valve or egr but brand new iacv.

i started with tps. ohms tested and had a dead spot and unstabke readings. have 5 volts reference. then tested vss and no reading while spinning tires on jack stands. then tested iat and the sensor was reading 3.5k ohms but no voltage to connector. yes i checked for voltage koeo.

my questions are what will a bad vss cause, bad tps cause, and iat probably thinks its unplugged but what will it do. i also sprayed for vacuum leaks and checked all my hoses.

also i just looked up the sensor testing thread on here that i have book marked for s&g and my tps has green/white wire and map sensor has green blue. what will switching these cause?

btw for thos who dont know this is a 90 crx si with obd1 h22a

yes i searched and dont have a definiteive answer from experience on all .

thanks in advance.

 

did i forget to say please?

 

nobody?

 

Check for input voltage to all sensors and a ground first then out put voltage I don't have my helms but ill help when I get home. Iat and tps should have 5 volts check for breaks in the harness back to the ecu.

 

And your iat readings sound really high that sensor may be worn.

 

If you can takke the dead end connector plugs off and check for voltage there at the yellow blk wires for 12v and the blk green sensor voltage for 5 volts. And test continuity from the blk to youur ground. If there's a problem there you can start taking apart your harness and look for breaks. These older harness wires break easily.

 

the tps has reference voltage, the iat does not. but i think the tps has been switched due to wire colors. looks like the map and tps are switched per this link....
https://honda-tech.com/forums/tech-misc-15/honda-sensors-resistance-chart-anyone-has-1817082/